Merge branch 'inference-bug'

# Conflicts:
#	lyngio/src/commonMain/kotlin/net/sergeych/lyng/io/http/LyngHttpModule.kt

docs/ai_language_reference.md

@@ -1,5 +1,7 @@
 # Lyng Language Reference for AI Agents (Current Compiler State)
 
+[//]: # (excludeFromIndex)
+
 Purpose: dense, implementation-first reference for generating valid Lyng code.
 
 Primary sources used: `lynglib/src/commonMain/kotlin/net/sergeych/lyng/{Parser,Token,Compiler,Script,TypeDecl}.kt`, `lynglib/stdlib/lyng/root.lyng`, tests in `lynglib/src/commonTest` and `lynglib/src/jvmTest`.

docs/ai_notes_wasm_generation_bug.md

@@ -1,5 +1,7 @@
 # AI notes: avoid Kotlin/Wasm invalid IR with suspend lambdas
 
+[//]: # (excludeFromIndex)
+
 ## Do
 - Prefer explicit `object : Statement()` with `override suspend fun execute(...)` when building compiler statements.
 - Keep `Statement` objects non-lambda, especially in compiler hot paths like parsing/var declarations.

docs/ai_stdlib_reference.md

@@ -1,5 +1,7 @@
 # Lyng Stdlib Reference for AI Agents (Compact)
 
+[//]: # (excludeFromIndex)
+
 Purpose: fast overview of what is available by default and what must be imported.
 
 Sources: `lynglib/src/commonMain/kotlin/net/sergeych/lyng/Script.kt`, `lynglib/stdlib/lyng/root.lyng`, `lynglib/src/commonMain/kotlin/net/sergeych/lyng/stdlib_included/observable_lyng.kt`.
@@ -82,8 +84,11 @@ Requires installing `lyngio` into the import manager from host code.
 - `import lyng.io.fs` (filesystem `Path` API)
 - `import lyng.io.process` (process execution API)
 - `import lyng.io.console` (console capabilities, geometry, ANSI/output, events)
+- `import lyng.io.http` (HTTP/HTTPS client API)
+- `import lyng.io.ws` (WebSocket client API; currently supported on JVM, capability-gated elsewhere)
+- `import lyng.io.net` (TCP/UDP transport API; currently supported on JVM, capability-gated elsewhere)
 
 ## 7. AI Generation Tips
 - Assume `lyng.stdlib` APIs exist in regular script contexts.
-- For platform-sensitive code (`fs`, `process`, `console`), gate assumptions and mention required module install.
+- For platform-sensitive code (`fs`, `process`, `console`, `http`, `ws`, `net`), gate assumptions and mention required module install.
 - Prefer extension-method style (`items.filter { ... }`) and standard scope helpers (`let`/`also`/`apply`/`run`).

docs/downloads.md

@@ -0,0 +1,11 @@
+# Some resources to download
+
+## Lync CLI tool
+
+- [lyng-linuxX64.zip](/distributables/lyng-linuxX64.zip) CLI tool for linuxX64: nodependencies, small monolith executable binary.
+
+## IDE plugins
+
+- [lyng-textmate.zip](../../lyng/distributables/lyng-textmate.zip) Texmate-compatible bundle with syntax coloring (could be outdated)
+
+- [lyng-idea-0.0.5-SNAPSHOT.zip](/distributables/lyng-idea-0.0.5-SNAPSHOT.zip) - plugin for IntelliJ-compatible IDE

docs/embedding.md

@@ -1,5 +1,7 @@
 # Embedding Lyng in your Kotlin project
 
+[//]: # (topMenu)
+
 Lyng is a tiny, embeddable, Kotlin‑first scripting language. This page shows, step by step, how to:
 
 - add Lyng to your build

docs/lyng.io.http.md

@@ -0,0 +1,179 @@
+### lyng.io.http — HTTP/HTTPS client for Lyng scripts
+
+This module provides a compact HTTP client API for Lyng scripts. It is implemented in `lyngio` and backed by Ktor on supported runtimes.
+
+> **Note:** `lyngio` is a separate library module. It must be explicitly added as a dependency to your host application and initialized in your Lyng scopes.
+
+---
+
+#### Add the library to your project (Gradle)
+
+If you use this repository as a multi-module project, add a dependency on `:lyngio`:
+
+```kotlin
+dependencies {
+    implementation("net.sergeych:lyngio:0.0.1-SNAPSHOT")
+}
+```
+
+For external projects, ensure you also use the Lyng Maven repository described in `lyng.io.fs`.
+
+---
+
+#### Install the module into a Lyng session
+
+The HTTP module is not installed automatically. Install it into the session scope and provide a policy.
+
+Kotlin (host) bootstrap example:
+
+```kotlin
+import net.sergeych.lyng.EvalSession
+import net.sergeych.lyng.Scope
+import net.sergeych.lyng.io.http.createHttpModule
+import net.sergeych.lyngio.http.security.PermitAllHttpAccessPolicy
+
+suspend fun bootstrapHttp() {
+    val session = EvalSession()
+    val scope: Scope = session.getScope()
+    createHttpModule(PermitAllHttpAccessPolicy, scope)
+    session.eval("import lyng.io.http")
+}
+```
+
+---
+
+#### Using from Lyng scripts
+
+Simple GET:
+
+    import lyng.io.http
+
+    val r = Http.get(HTTP_TEST_URL + "/hello")
+    [r.status, r.text()]
+    >>> [200,hello from test]
+
+Headers and response header access:
+
+    import lyng.io.http
+
+    val r = Http.get(HTTP_TEST_URL + "/headers")
+    [r.headers["X-Reply"], r.headers.getAll("X-Reply").size, r.text()]
+    >>> [one,2,header demo]
+
+Programmatic request object:
+
+    import lyng.io.http
+
+    val q = HttpRequest()
+    q.method = "POST"
+    q.url = HTTP_TEST_URL + "/echo"
+    q.headers = Map("Content-Type" => "text/plain")
+    q.bodyText = "ping"
+
+    val r = Http.request(q)
+    r.text()
+    >>> "POST:ping"
+
+HTTPS GET:
+
+    import lyng.io.http
+
+    val r = Http.get(HTTPS_TEST_URL + "/hello")
+    [r.status, r.text()]
+    >>> [200,hello from test]
+
+---
+
+#### API reference
+
+##### `Http` (static methods)
+
+- `isSupported(): Bool` — Whether HTTP client support is available on the current runtime.
+- `request(req: HttpRequest): HttpResponse` — Execute a request described by a mutable request object.
+- `get(url: String, headers...): HttpResponse` — Convenience GET request.
+- `post(url: String, bodyText: String = "", contentType: String? = null, headers...): HttpResponse` — Convenience text POST request.
+- `postBytes(url: String, body: Buffer, contentType: String? = null, headers...): HttpResponse` — Convenience binary POST request.
+
+For convenience methods, `headers...` accepts:
+
+- `MapEntry`, e.g. `"Accept" => "text/plain"`
+- 2-item lists, e.g. `["Accept", "text/plain"]`
+
+##### `HttpRequest`
+
+- `method: String`
+- `url: String`
+- `headers: Map<String, String>`
+- `bodyText: String?`
+- `bodyBytes: Buffer?`
+- `timeoutMillis: Int?`
+
+Only one of `bodyText` and `bodyBytes` should be set.
+
+##### `HttpResponse`
+
+- `status: Int`
+- `statusText: String`
+- `headers: HttpHeaders`
+- `text(): String`
+- `bytes(): Buffer`
+
+Response body decoding is cached inside the response object.
+
+##### `HttpHeaders`
+
+`HttpHeaders` behaves like `Map<String, String>` for the first value of each header name and additionally exposes:
+
+- `get(name: String): String?`
+- `getAll(name: String): List<String>`
+- `names(): List<String>`
+
+Header lookup is case-insensitive.
+
+---
+
+#### Security policy
+
+The module uses `HttpAccessPolicy` to authorize requests before they are sent.
+
+- `HttpAccessPolicy` — interface for custom policies
+- `PermitAllHttpAccessPolicy` — allows all requests
+- `HttpAccessOp.Request(method, url)` — operation checked by the policy
+
+Example restricted policy in Kotlin:
+
+```kotlin
+import net.sergeych.lyngio.fs.security.AccessContext
+import net.sergeych.lyngio.fs.security.AccessDecision
+import net.sergeych.lyngio.fs.security.Decision
+import net.sergeych.lyngio.http.security.HttpAccessOp
+import net.sergeych.lyngio.http.security.HttpAccessPolicy
+
+val allowLocalOnly = object : HttpAccessPolicy {
+    override suspend fun check(op: HttpAccessOp, ctx: AccessContext): AccessDecision =
+        when (op) {
+            is HttpAccessOp.Request ->
+                if (
+                    op.url.startsWith("http://127.0.0.1:") ||
+                    op.url.startsWith("https://127.0.0.1:") ||
+                    op.url.startsWith("http://localhost:") ||
+                    op.url.startsWith("https://localhost:")
+                )
+                    AccessDecision(Decision.Allow)
+                else
+                    AccessDecision(Decision.Deny, "only local HTTP/HTTPS requests are allowed")
+        }
+}
+```
+
+---
+
+#### Platform support
+
+- **JVM:** supported
+- **Android:** supported via the Ktor CIO client backend
+- **JS:** supported via the Ktor JS client backend
+- **Linux native:** supported via the Ktor Curl client backend
+- **Windows native:** supported via the Ktor WinHttp client backend
+- **Apple native:** supported via the Ktor Darwin client backend
+- **Other targets:** may report unsupported; use `Http.isSupported()` before relying on it

docs/lyng.io.net.md

@@ -0,0 +1,169 @@
+### lyng.io.net — TCP and UDP sockets for Lyng scripts
+
+This module provides minimal raw transport networking for Lyng scripts. It is implemented in `lyngio` and backed by Ktor sockets on the JVM and Linux Native, and by Node networking APIs on JS/Node runtimes.
+
+> **Note:** `lyngio` is a separate library module. It must be explicitly added as a dependency to your host application and initialized in your Lyng scopes.
+
+---
+
+#### Install the module into a Lyng session
+
+Kotlin (host) bootstrap example:
+
+```kotlin
+import net.sergeych.lyng.EvalSession
+import net.sergeych.lyng.Scope
+import net.sergeych.lyng.io.net.createNetModule
+import net.sergeych.lyngio.net.security.PermitAllNetAccessPolicy
+
+suspend fun bootstrapNet() {
+    val session = EvalSession()
+    val scope: Scope = session.getScope()
+    createNetModule(PermitAllNetAccessPolicy, scope)
+    session.eval("import lyng.io.net")
+}
+```
+
+---
+
+#### Using from Lyng scripts
+
+Capability checks and address resolution:
+
+    import lyng.io.net
+
+    val a: SocketAddress = Net.resolve("127.0.0.1", 4040)[0]
+    [Net.isSupported(), a.toString(), a.resolved, a.ipVersion == IpVersion.IPV4]
+    >>> [true,127.0.0.1:4040,true,true]
+
+TCP client connect, write, read, and close:
+
+    import lyng.buffer
+    import lyng.io.net
+
+    val socket = Net.tcpConnect("127.0.0.1", NET_TEST_TCP_PORT)
+    socket.writeUtf8("ping")
+    socket.flush()
+    val reply = (socket.read(16) as Buffer).decodeUtf8()
+    socket.close()
+    reply
+    >>> "reply:ping"
+
+Lyng TCP server socket operations with `tcpListen()` and `accept()`:
+
+    import lyng.buffer
+    import lyng.io.net
+
+    val server = Net.tcpListen(0, "127.0.0.1")
+    val port = server.localAddress().port
+    val accepted = launch {
+        val client = server.accept()
+        val line = (client.read(4) as Buffer).decodeUtf8()
+        client.writeUtf8("echo:" + line)
+        client.flush()
+        client.close()
+        server.close()
+        line
+    }
+
+    val socket = Net.tcpConnect("127.0.0.1", port)
+    socket.writeUtf8("ping")
+    socket.flush()
+    val reply = (socket.read(16) as Buffer).decodeUtf8()
+    socket.close()
+    [accepted.await(), reply]
+    >>> [ping,echo:ping]
+
+UDP bind, send, receive, and inspect sender address:
+
+    import lyng.buffer
+    import lyng.io.net
+
+    val server = Net.udpBind(0, "127.0.0.1")
+    val client = Net.udpBind(0, "127.0.0.1")
+    client.send(Buffer("ping"), "127.0.0.1", server.localAddress().port)
+    val d = server.receive()
+    client.close()
+    server.close()
+    [d.data.decodeUtf8(), d.address.port > 0]
+    >>> [ping,true]
+
+---
+
+#### API reference
+
+##### `Net` (static methods)
+
+- `isSupported(): Bool` — Whether any raw networking support is available.
+- `isTcpAvailable(): Bool` — Whether outbound TCP sockets are available.
+- `isTcpServerAvailable(): Bool` — Whether listening TCP server sockets are available.
+- `isUdpAvailable(): Bool` — Whether UDP datagram sockets are available.
+- `resolve(host: String, port: Int): List<SocketAddress>` — Resolve a host and port into concrete addresses.
+- `tcpConnect(host: String, port: Int, timeoutMillis: Int? = null, noDelay: Bool = true): TcpSocket` — Open an outbound TCP socket.
+- `tcpListen(port: Int, host: String? = null, backlog: Int = 128, reuseAddress: Bool = true): TcpServer` — Start a listening TCP server socket.
+- `udpBind(port: Int = 0, host: String? = null, reuseAddress: Bool = true): UdpSocket` — Bind a UDP socket.
+
+##### `SocketAddress`
+
+- `host: String`
+- `port: Int`
+- `ipVersion: IpVersion`
+- `resolved: Bool`
+- `toString(): String`
+
+##### `TcpSocket`
+
+- `isOpen(): Bool`
+- `localAddress(): SocketAddress`
+- `remoteAddress(): SocketAddress`
+- `read(maxBytes: Int = 65536): Buffer?`
+- `readLine(): String?`
+- `write(data: Buffer): void`
+- `writeUtf8(text: String): void`
+- `flush(): void`
+- `close(): void`
+
+##### `TcpServer`
+
+- `isOpen(): Bool`
+- `localAddress(): SocketAddress`
+- `accept(): TcpSocket`
+- `close(): void`
+
+##### `UdpSocket`
+
+- `isOpen(): Bool`
+- `localAddress(): SocketAddress`
+- `receive(maxBytes: Int = 65536): Datagram?`
+- `send(data: Buffer, host: String, port: Int): void`
+- `close(): void`
+
+##### `Datagram`
+
+- `data: Buffer`
+- `address: SocketAddress`
+
+---
+
+#### Security policy
+
+The module uses `NetAccessPolicy` to authorize network operations before they are executed.
+
+- `NetAccessPolicy` — interface for custom policies
+- `PermitAllNetAccessPolicy` — allows all network operations
+- `NetAccessOp.Resolve(host, port)`
+- `NetAccessOp.TcpConnect(host, port)`
+- `NetAccessOp.TcpListen(host, port, backlog)`
+- `NetAccessOp.UdpBind(host, port)`
+
+---
+
+#### Platform support
+
+- **JVM:** supported
+- **Android:** supported via the Ktor CIO and Ktor sockets backends
+- **JS/Node:** supported for `resolve`, TCP client/server, and UDP
+- **JS/browser:** unsupported; capability checks report unavailable
+- **Linux Native:** supported via Ktor sockets
+- **Apple Native:** enabled via the shared native Ktor sockets backend; compile-verified, runtime not yet host-verified
+- **Other native targets:** currently report unsupported; use capability checks before relying on raw sockets

docs/lyng.io.ws.md

@@ -0,0 +1,148 @@
+### lyng.io.ws — WebSocket client for Lyng scripts
+
+This module provides a compact WebSocket client API for Lyng scripts. It is implemented in `lyngio` and currently backed by Ktor WebSockets on the JVM.
+
+> **Note:** `lyngio` is a separate library module. It must be explicitly added as a dependency to your host application and initialized in your Lyng scopes.
+
+---
+
+#### Install the module into a Lyng session
+
+Kotlin (host) bootstrap example:
+
+```kotlin
+import net.sergeych.lyng.EvalSession
+import net.sergeych.lyng.Scope
+import net.sergeych.lyng.io.ws.createWsModule
+import net.sergeych.lyngio.ws.security.PermitAllWsAccessPolicy
+
+suspend fun bootstrapWs() {
+    val session = EvalSession()
+    val scope: Scope = session.getScope()
+    createWsModule(PermitAllWsAccessPolicy, scope)
+    session.eval("import lyng.io.ws")
+}
+```
+
+---
+
+#### Using from Lyng scripts
+
+Simple text message exchange:
+
+    import lyng.io.ws
+
+    val ws = Ws.connect(WS_TEST_URL)
+    ws.sendText("ping")
+    val m: WsMessage = ws.receive()
+    ws.close()
+    [ws.url() == WS_TEST_URL, m.isText, m.text]
+    >>> [true,true,echo:ping]
+
+Binary message exchange:
+
+    import lyng.buffer
+    import lyng.io.ws
+
+    val ws = Ws.connect(WS_TEST_BINARY_URL)
+    ws.sendBytes(Buffer(9, 8, 7))
+    val m: WsMessage = ws.receive()
+    ws.close()
+    [m.isText, (m.data as Buffer).hex]
+    >>> [false,010203090807]
+
+Secure websocket (`wss`) exchange:
+
+    import lyng.io.ws
+
+    val ws = Ws.connect(WSS_TEST_URL)
+    ws.sendText("ping")
+    val m: WsMessage = ws.receive()
+    ws.close()
+    [ws.url() == WSS_TEST_URL, m.text]
+    >>> [true,secure:ping]
+
+---
+
+#### API reference
+
+##### `Ws` (static methods)
+
+- `isSupported(): Bool` — Whether WebSocket client support is available on the current runtime.
+- `connect(url: String, headers...): WsSession` — Open a client websocket session.
+
+`headers...` accepts:
+
+- `MapEntry`, e.g. `"Authorization" => "Bearer x"`
+- 2-item lists, e.g. `["Authorization", "Bearer x"]`
+
+##### `WsSession`
+
+- `isOpen(): Bool`
+- `url(): String`
+- `sendText(text: String): void`
+- `sendBytes(data: Buffer): void`
+- `receive(): WsMessage?`
+- `close(code: Int = 1000, reason: String = ""): void`
+
+`receive()` returns `null` after a clean close.
+
+##### `WsMessage`
+
+- `isText: Bool`
+- `text: String?`
+- `data: Buffer?`
+
+Text messages populate `text`; binary messages populate `data`.
+
+---
+
+#### Security policy
+
+The module uses `WsAccessPolicy` to authorize websocket operations.
+
+- `WsAccessPolicy` — interface for custom policies
+- `PermitAllWsAccessPolicy` — allows all websocket operations
+- `WsAccessOp.Connect(url)`
+- `WsAccessOp.Send(url, bytes, isText)`
+- `WsAccessOp.Receive(url)`
+
+Example restricted policy in Kotlin:
+
+```kotlin
+import net.sergeych.lyngio.fs.security.AccessContext
+import net.sergeych.lyngio.fs.security.AccessDecision
+import net.sergeych.lyngio.fs.security.Decision
+import net.sergeych.lyngio.ws.security.WsAccessOp
+import net.sergeych.lyngio.ws.security.WsAccessPolicy
+
+val allowLocalOnly = object : WsAccessPolicy {
+    override suspend fun check(op: WsAccessOp, ctx: AccessContext): AccessDecision =
+        when (op) {
+            is WsAccessOp.Connect ->
+                if (
+                    op.url.startsWith("ws://127.0.0.1:") ||
+                    op.url.startsWith("wss://127.0.0.1:") ||
+                    op.url.startsWith("ws://localhost:") ||
+                    op.url.startsWith("wss://localhost:")
+                )
+                    AccessDecision(Decision.Allow)
+                else
+                    AccessDecision(Decision.Deny, "only local ws/wss connections are allowed")
+
+            else -> AccessDecision(Decision.Allow)
+        }
+}
+```
+
+---
+
+#### Platform support
+
+- **JVM:** supported
+- **Android:** supported via the Ktor CIO websocket client backend
+- **JS:** supported via the Ktor JS websocket client backend
+- **Linux native:** supported via the Ktor Curl websocket client backend
+- **Windows native:** supported via the Ktor WinHttp websocket client backend
+- **Apple native:** supported via the Ktor Darwin websocket client backend
+- **Other targets:** may report unsupported; use `Ws.isSupported()` before relying on websocket client access

docs/lyngio.md

@@ -13,6 +13,9 @@
 - **[lyng.io.fs](lyng.io.fs.md):** Async filesystem access. Provides the `Path` class for file/directory operations, streaming, and globbing.
 - **[lyng.io.process](lyng.io.process.md):** External process execution and shell commands. Provides `Process`, `RunningProcess`, and `Platform` information.
 - **[lyng.io.console](lyng.io.console.md):** Rich console/TTY access. Provides `Console` capability detection, geometry, output, and iterable events.
+- **[lyng.io.http](lyng.io.http.md):** HTTP/HTTPS client access. Provides `Http`, `HttpRequest`, `HttpResponse`, and `HttpHeaders`.
+- **[lyng.io.ws](lyng.io.ws.md):** WebSocket client access. Provides `Ws`, `WsSession`, and `WsMessage`.
+- **[lyng.io.net](lyng.io.net.md):** Transport networking. Provides `Net`, `TcpSocket`, `TcpServer`, `UdpSocket`, and `SocketAddress`.
 
 ---
 
@@ -41,9 +44,15 @@ import net.sergeych.lyng.EvalSession
 import net.sergeych.lyng.io.fs.createFs
 import net.sergeych.lyng.io.process.createProcessModule
 import net.sergeych.lyng.io.console.createConsoleModule
+import net.sergeych.lyng.io.http.createHttpModule
+import net.sergeych.lyng.io.net.createNetModule
+import net.sergeych.lyng.io.ws.createWsModule
 import net.sergeych.lyngio.fs.security.PermitAllAccessPolicy
 import net.sergeych.lyngio.process.security.PermitAllProcessAccessPolicy
 import net.sergeych.lyngio.console.security.PermitAllConsoleAccessPolicy
+import net.sergeych.lyngio.http.security.PermitAllHttpAccessPolicy
+import net.sergeych.lyngio.net.security.PermitAllNetAccessPolicy
+import net.sergeych.lyngio.ws.security.PermitAllWsAccessPolicy
 
 suspend fun runMyScript() {
     val session = EvalSession()
@@ -53,16 +62,25 @@ suspend fun runMyScript() {
     createFs(PermitAllAccessPolicy, scope)
     createProcessModule(PermitAllProcessAccessPolicy, scope)
     createConsoleModule(PermitAllConsoleAccessPolicy, scope)
+    createHttpModule(PermitAllHttpAccessPolicy, scope)
+    createNetModule(PermitAllNetAccessPolicy, scope)
+    createWsModule(PermitAllWsAccessPolicy, scope)
     
     // Now scripts can import them
     session.eval("""
         import lyng.io.fs
         import lyng.io.process
         import lyng.io.console
+        import lyng.io.http
+        import lyng.io.net
+        import lyng.io.ws
         
         println("Working dir: " + Path(".").readUtf8())
         println("OS: " + Platform.details().name)
         println("TTY: " + Console.isTty())
+        println("HTTP available: " + Http.isSupported())
+        println("TCP available: " + Net.isTcpAvailable())
+        println("WS available: " + Ws.isSupported())
     """)
 }
 ```
@@ -76,21 +94,27 @@ suspend fun runMyScript() {
 - **Filesystem Security:** Implement `FsAccessPolicy` to restrict access to specific paths or operations (e.g., read-only access to a sandbox directory).
 - **Process Security:** Implement `ProcessAccessPolicy` to restrict which executables can be run or to disable shell execution entirely.
 - **Console Security:** Implement `ConsoleAccessPolicy` to control output writes, event reads, and raw mode switching.
+- **HTTP Security:** Implement `HttpAccessPolicy` to restrict which requests scripts may send.
+- **Transport Security:** Implement `NetAccessPolicy` to restrict DNS resolution and TCP/UDP socket operations.
+- **WebSocket Security:** Implement `WsAccessPolicy` to restrict websocket connects and message flow.
 
 For more details, see the specific module documentation:
 - [Filesystem Security Details](lyng.io.fs.md#access-policy-security)
 - [Process Security Details](lyng.io.process.md#security-policy)
 - [Console Module Details](lyng.io.console.md)
+- [HTTP Module Details](lyng.io.http.md)
+- [Transport Networking Details](lyng.io.net.md)
+- [WebSocket Module Details](lyng.io.ws.md)
 
 ---
 
 #### Platform Support Overview
 
-| Platform | lyng.io.fs | lyng.io.process | lyng.io.console |
+| Platform | lyng.io.fs | lyng.io.process | lyng.io.console | lyng.io.http | lyng.io.ws | lyng.io.net |
-| :--- | :---: | :---: | :---: |
+| :--- | :---: | :---: | :---: | :---: | :---: | :---: |
-| **JVM** | ✅ | ✅ | ✅ (baseline) |
+| **JVM** | ✅ | ✅ | ✅ (baseline) | ✅ | ✅ | ✅ |
-| **Native (Linux/macOS)** | ✅ | ✅ | 🚧 |
+| **Native (Linux/macOS)** | ✅ | ✅ | 🚧 | 🚧 | 🚧 | 🚧 |
-| **Native (Windows)** | ✅ | 🚧 (Planned) | 🚧 |
+| **Native (Windows)** | ✅ | 🚧 (Planned) | 🚧 | 🚧 | 🚧 | 🚧 |
-| **Android** | ✅ | ❌ | ❌ |
+| **Android** | ✅ | ❌ | ❌ | 🚧 | 🚧 | 🚧 |
-| **NodeJS** | ✅ | ❌ | ❌ |
+| **NodeJS** | ✅ | ❌ | ❌ | 🚧 | 🚧 | 🚧 |
-| **Browser / Wasm** | ✅ (In-memory) | ❌ | ❌ |
+| **Browser / Wasm** | ✅ (In-memory) | ❌ | ❌ | 🚧 | 🚧 | 🚧 |

examples/tetris_console.lyng

@@ -49,6 +49,7 @@ val UNICODE_BOTTOM_RIGHT = "┘"
 val UNICODE_HORIZONTAL = "──"
 val UNICODE_VERTICAL = "│"
 val UNICODE_DOT = "· "
+val PIECES: List<Piece> = []
 
 type Cell = List<Int>
 type Rotation = List<Cell>
@@ -468,8 +469,6 @@ fun rot(a: Cell, b: Cell, c: Cell, d: Cell): Rotation {
     r
 }
 
-val PIECES: List<Piece> = []
-
 val iRots: Rotations = []
 iRots.add(rot(cell(0,1), cell(1,1), cell(2,1), cell(3,1)))
 iRots.add(rot(cell(2,0), cell(2,1), cell(2,2), cell(2,3)))

gradle/libs.versions.toml

@@ -13,6 +13,7 @@ multik = "0.3.0"
 firebaseCrashlyticsBuildtools = "3.0.3"
 okioVersion = "3.10.2"
 compiler = "3.2.0-alpha11"
+ktor = "3.3.1"
 
 [libraries]
 clikt = { module = "com.github.ajalt.clikt:clikt", version.ref = "clikt" }
@@ -31,6 +32,14 @@ okio = { module = "com.squareup.okio:okio", version.ref = "okioVersion" }
 okio-fakefilesystem = { module = "com.squareup.okio:okio-fakefilesystem", version.ref = "okioVersion" }
 okio-nodefilesystem = { module = "com.squareup.okio:okio-nodefilesystem", version.ref = "okioVersion" }
 compiler = { group = "androidx.databinding", name = "compiler", version.ref = "compiler" }
+ktor-client-core = { module = "io.ktor:ktor-client-core", version.ref = "ktor" }
+ktor-client-cio = { module = "io.ktor:ktor-client-cio", version.ref = "ktor" }
+ktor-client-curl = { module = "io.ktor:ktor-client-curl", version.ref = "ktor" }
+ktor-client-darwin = { module = "io.ktor:ktor-client-darwin", version.ref = "ktor" }
+ktor-client-js = { module = "io.ktor:ktor-client-js", version.ref = "ktor" }
+ktor-client-winhttp = { module = "io.ktor:ktor-client-winhttp", version.ref = "ktor" }
+ktor-client-websockets = { module = "io.ktor:ktor-client-websockets", version.ref = "ktor" }
+ktor-network = { module = "io.ktor:ktor-network", version.ref = "ktor" }
 
 [plugins]
 androidLibrary = { id = "com.android.library", version.ref = "agp" }

lyng/src/jvmTest/kotlin/net/sergeych/lyng_cli/FsIntegrationJvmTest.kt

@@ -31,11 +31,12 @@ class FsIntegrationJvmTest {
             val dir = createTempDirectory("lyng_cli_fs_test_")
             try {
                 val file = dir.resolve("hello.txt")
+                val filePath = file.toString().replace("\\", "\\\\")
                 // Drive the operation via Lyng code to validate bindings end-to-end
                 scope.eval(
                     """
                     import lyng.io.fs
-                    val p = Path("${'$'}{file}")
+                    val p = Path("${filePath}")
                     p.writeUtf8("hello from cli test")
                     assertEquals(true, p.exists())
                     assertEquals("hello from cli test", p.readUtf8())

lyngio/build.gradle.kts

@@ -80,28 +80,49 @@ kotlin {
                 api(libs.okio)
                 api(libs.kotlinx.coroutines.core)
                 api(libs.mordant.core)
+                api(libs.ktor.client.core)
+                implementation(libs.ktor.client.websockets)
             }
         }
         val nativeMain by creating {
             dependsOn(commonMain)
+            dependencies {
+                implementation(libs.ktor.network)
+            }
+        }
+        val darwinMain by creating {
+            dependsOn(nativeMain)
+            dependencies {
+                implementation(libs.ktor.client.darwin)
+            }
         }
         val iosMain by creating {
-            dependsOn(nativeMain)
+            dependsOn(darwinMain)
         }
         val linuxMain by creating {
             dependsOn(nativeMain)
+            dependencies {
+                implementation(libs.ktor.client.curl)
+            }
         }
         val macosMain by creating {
-            dependsOn(nativeMain)
+            dependsOn(darwinMain)
         }
         val mingwMain by creating {
             dependsOn(nativeMain)
+            dependencies {
+                implementation(libs.ktor.client.winhttp)
+            }
         }
         val commonTest by getting {
             dependencies {
                 implementation(libs.kotlin.test)
+                implementation(libs.kotlinx.coroutines.test)
             }
         }
+        val linuxTest by creating {
+            dependsOn(commonTest)
+        }
         val iosX64Main by getting { dependsOn(iosMain) }
         val iosArm64Main by getting { dependsOn(iosMain) }
         val iosSimulatorArm64Main by getting { dependsOn(iosMain) }
@@ -109,6 +130,8 @@ kotlin {
         val mingwX64Main by getting { dependsOn(mingwMain) }
         val linuxX64Main by getting { dependsOn(linuxMain) }
         val linuxArm64Main by getting { dependsOn(linuxMain) }
+        val linuxX64Test by getting { dependsOn(linuxTest) }
+        val linuxArm64Test by getting { dependsOn(linuxTest) }
 
         // JS: use runtime detection in jsMain to select Node vs Browser implementation
         val jsMain by getting {
@@ -116,6 +139,13 @@ kotlin {
                 api(libs.okio)
                 implementation(libs.okio.fakefilesystem)
                 implementation("com.squareup.okio:okio-nodefilesystem:${libs.versions.okioVersion.get()}")
+                implementation(libs.ktor.client.js)
+            }
+        }
+        val androidMain by getting {
+            dependencies {
+                implementation(libs.ktor.client.cio)
+                implementation(libs.ktor.network)
             }
         }
         val jvmMain by getting {
@@ -123,6 +153,8 @@ kotlin {
                 implementation(libs.mordant.jvm.jna)
                 implementation("org.jline:jline-reader:3.29.0")
                 implementation("org.jline:jline-terminal:3.29.0")
+                implementation(libs.ktor.client.cio)
+                implementation(libs.ktor.network)
             }
         }
 //        // For Wasm we use in-memory VFS for now
@@ -135,10 +167,10 @@ kotlin {
     }
 }
 
-abstract class GenerateLyngioConsoleDecls : DefaultTask() {
+abstract class GenerateLyngioDecls : DefaultTask() {
-    @get:InputFile
+    @get:InputDirectory
     @get:PathSensitive(PathSensitivity.RELATIVE)
-    abstract val sourceFile: RegularFileProperty
+    abstract val sourceDir: DirectoryProperty
 
     @get:OutputDirectory
     abstract val outputDir: DirectoryProperty
@@ -148,9 +180,9 @@ abstract class GenerateLyngioConsoleDecls : DefaultTask() {
         val targetPkg = "net.sergeych.lyngio.stdlib_included"
         val pkgPath = targetPkg.replace('.', '/')
         val targetDir = outputDir.get().asFile.resolve(pkgPath)
+        if (targetDir.exists()) targetDir.deleteRecursively()
         targetDir.mkdirs()
 
-        val text = sourceFile.get().asFile.readText()
         fun escapeForQuoted(s: String): String = buildString {
             for (ch in s) when (ch) {
                 '\\' -> append("\\\\")
@@ -165,30 +197,39 @@ abstract class GenerateLyngioConsoleDecls : DefaultTask() {
         val out = buildString {
             append("package ").append(targetPkg).append("\n\n")
             append("@Suppress(\"Unused\", \"MemberVisibilityCanBePrivate\")\n")
-            append("internal val consoleLyng = \"")
+            sourceDir.get().asFile
-            append(escapeForQuoted(text))
+                .listFiles { file -> file.isFile && file.extension == "lyng" }
-            append("\"\n")
+                ?.sortedBy { it.name }
+                ?.forEach { file ->
+                    val propertyName = buildString {
+                        append(file.nameWithoutExtension)
+                        append("Lyng")
+                    }
+                    append("internal val ").append(propertyName).append(" = \"")
+                    append(escapeForQuoted(file.readText()))
+                    append("\"\n")
+                }
         }
-        targetDir.resolve("console_types_lyng.generated.kt").writeText(out)
+        targetDir.resolve("lyngio_types_lyng.generated.kt").writeText(out)
     }
 }
 
-val lyngioConsoleDeclsFile = layout.projectDirectory.file("stdlib/lyng/io/console.lyng")
+val lyngioDeclsDir = layout.projectDirectory.dir("stdlib/lyng/io")
 val generatedLyngioDeclsDir = layout.buildDirectory.dir("generated/source/lyngioDecls/commonMain/kotlin")
 
-val generateLyngioConsoleDecls by tasks.registering(GenerateLyngioConsoleDecls::class) {
+val generateLyngioDecls by tasks.registering(GenerateLyngioDecls::class) {
-    sourceFile.set(lyngioConsoleDeclsFile)
+    sourceDir.set(lyngioDeclsDir)
     outputDir.set(generatedLyngioDeclsDir)
 }
 
 kotlin.sourceSets.named("commonMain") {
-    kotlin.srcDir(generateLyngioConsoleDecls)
+    kotlin.srcDir(generateLyngioDecls)
 }
 
 kotlin.targets.configureEach {
     compilations.configureEach {
         compileTaskProvider.configure {
-            dependsOn(generateLyngioConsoleDecls)
+            dependsOn(generateLyngioDecls)
         }
     }
 }

lyngio/src/androidMain/kotlin/net/sergeych/lyngio/http/PlatformAndroid.kt

@@ -0,0 +1,5 @@
+package net.sergeych.lyngio.http
+
+import io.ktor.client.engine.cio.CIO
+
+actual fun getSystemHttpEngine(): LyngHttpEngine = createKtorHttpEngine(CIO)

lyngio/src/androidMain/kotlin/net/sergeych/lyngio/net/PlatformAndroid.kt

@@ -0,0 +1,206 @@
+package net.sergeych.lyngio.net
+
+import io.ktor.network.selector.ActorSelectorManager
+import io.ktor.network.selector.SelectorManager
+import io.ktor.network.sockets.BoundDatagramSocket
+import io.ktor.network.sockets.InetSocketAddress
+import io.ktor.network.sockets.ServerSocket
+import io.ktor.network.sockets.Socket
+import io.ktor.network.sockets.aSocket
+import io.ktor.network.sockets.isClosed
+import io.ktor.network.sockets.openReadChannel
+import io.ktor.network.sockets.openWriteChannel
+import io.ktor.network.sockets.toJavaAddress
+import io.ktor.utils.io.ByteReadChannel
+import io.ktor.utils.io.ByteWriteChannel
+import io.ktor.utils.io.readAvailable
+import io.ktor.utils.io.readUTF8Line
+import io.ktor.utils.io.writeFully
+import io.ktor.utils.io.writeStringUtf8
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.withContext
+import kotlinx.coroutines.withTimeout
+import kotlinx.io.Buffer
+import kotlinx.io.readByteArray
+import java.net.Inet4Address
+import java.net.Inet6Address
+import java.net.InetAddress
+
+actual fun getSystemNetEngine(): LyngNetEngine = AndroidKtorNetEngine
+
+private object AndroidKtorNetEngine : LyngNetEngine {
+    private val selectorManager: SelectorManager by lazy { ActorSelectorManager(Dispatchers.IO) }
+
+    override val isSupported: Boolean = true
+    override val isTcpAvailable: Boolean = true
+    override val isTcpServerAvailable: Boolean = true
+    override val isUdpAvailable: Boolean = true
+
+    override suspend fun resolve(host: String, port: Int): List<LyngSocketAddress> = withContext(Dispatchers.IO) {
+        InetAddress.getAllByName(host).map { address ->
+            address.toLyngSocketAddress(port = port, resolved = true)
+        }
+    }
+
+    override suspend fun tcpConnect(
+        host: String,
+        port: Int,
+        timeoutMillis: Long?,
+        noDelay: Boolean,
+    ): LyngTcpSocket {
+        val connectBlock: suspend () -> Socket = {
+            aSocket(selectorManager).tcp().connect(host, port) {
+                this.noDelay = noDelay
+            }
+        }
+        val socket = if (timeoutMillis != null) withTimeout(timeoutMillis) { connectBlock() } else connectBlock()
+        return AndroidLyngTcpSocket(socket)
+    }
+
+    override suspend fun tcpListen(
+        host: String?,
+        port: Int,
+        backlog: Int,
+        reuseAddress: Boolean,
+    ): LyngTcpServer {
+        val bindHost = host ?: "0.0.0.0"
+        val server = aSocket(selectorManager).tcp().bind(bindHost, port) {
+            backlogSize = backlog
+            this.reuseAddress = reuseAddress
+        }
+        return AndroidLyngTcpServer(server)
+    }
+
+    override suspend fun udpBind(host: String?, port: Int, reuseAddress: Boolean): LyngUdpSocket {
+        val bindHost = host ?: "0.0.0.0"
+        val socket = aSocket(selectorManager).udp().bind(bindHost, port) {
+            this.reuseAddress = reuseAddress
+        }
+        return AndroidLyngUdpSocket(socket)
+    }
+}
+
+private class AndroidLyngTcpSocket(
+    private val socket: Socket,
+) : LyngTcpSocket {
+    private val input: ByteReadChannel by lazy { socket.openReadChannel() }
+    private val output: ByteWriteChannel by lazy { socket.openWriteChannel(autoFlush = true) }
+
+    override fun isOpen(): Boolean = !socket.isClosed
+
+    override fun localAddress(): LyngSocketAddress = socket.localAddress.toLyngSocketAddress(resolved = true)
+
+    override fun remoteAddress(): LyngSocketAddress = socket.remoteAddress.toLyngSocketAddress(resolved = true)
+
+    override suspend fun read(maxBytes: Int): ByteArray? {
+        if (!input.awaitContent(1)) return null
+        val buffer = ByteArray(maxBytes)
+        val count = input.readAvailable(buffer, 0, maxBytes)
+        return when {
+            count <= 0 -> null
+            count == maxBytes -> buffer
+            else -> buffer.copyOf(count)
+        }
+    }
+
+    override suspend fun readLine(): String? = input.readUTF8Line()
+
+    override suspend fun write(data: ByteArray) {
+        output.writeFully(data, 0, data.size)
+    }
+
+    override suspend fun writeUtf8(text: String) {
+        output.writeStringUtf8(text)
+    }
+
+    override suspend fun flush() {
+        output.flush()
+    }
+
+    override fun close() {
+        socket.close()
+    }
+}
+
+private class AndroidLyngTcpServer(
+    private val server: ServerSocket,
+) : LyngTcpServer {
+    override fun isOpen(): Boolean = !server.isClosed
+
+    override fun localAddress(): LyngSocketAddress = server.localAddress.toLyngSocketAddress(resolved = true)
+
+    override suspend fun accept(): LyngTcpSocket = AndroidLyngTcpSocket(server.accept())
+
+    override fun close() {
+        server.close()
+    }
+}
+
+private class AndroidLyngUdpSocket(
+    private val socket: BoundDatagramSocket,
+) : LyngUdpSocket {
+    override fun isOpen(): Boolean = !socket.isClosed
+
+    override fun localAddress(): LyngSocketAddress = socket.localAddress.toLyngSocketAddress(resolved = true)
+
+    override suspend fun receive(maxBytes: Int): LyngDatagram? {
+        val datagram = try {
+            socket.receive()
+        } catch (e: Throwable) {
+            if (!isOpen()) return null
+            throw e
+        }
+        val bytes = datagram.packet.readByteArray().let {
+            if (it.size <= maxBytes) it else it.copyOf(maxBytes)
+        }
+        return LyngDatagram(bytes, datagram.address.toLyngSocketAddress(resolved = true))
+    }
+
+    override suspend fun send(data: ByteArray, host: String, port: Int) {
+        val packet = Buffer()
+        packet.write(data)
+        socket.send(io.ktor.network.sockets.Datagram(packet, InetSocketAddress(host, port)))
+    }
+
+    override fun close() {
+        socket.close()
+    }
+}
+
+private fun io.ktor.network.sockets.SocketAddress.toLyngSocketAddress(
+    port: Int? = null,
+    resolved: Boolean,
+): LyngSocketAddress {
+    val javaAddress = this.toJavaAddress()
+    val inetSocket = javaAddress as? java.net.InetSocketAddress
+    if (inetSocket != null) {
+        val inetAddress = inetSocket.address
+        val host = inetAddress?.hostAddress ?: inetSocket.hostString
+        val actualPort = port ?: inetSocket.port
+        val version = when (inetAddress) {
+            is Inet6Address -> LyngIpVersion.IPV6
+            is Inet4Address -> LyngIpVersion.IPV4
+            else -> if (host.contains(':')) LyngIpVersion.IPV6 else LyngIpVersion.IPV4
+        }
+        return LyngSocketAddress(host = host, port = actualPort, ipVersion = version, resolved = resolved)
+    }
+
+    val rendered = toString()
+    return LyngSocketAddress(
+        host = rendered,
+        port = port ?: 0,
+        ipVersion = if (rendered.contains(':')) LyngIpVersion.IPV6 else LyngIpVersion.IPV4,
+        resolved = resolved,
+    )
+}
+
+private fun InetAddress.toLyngSocketAddress(port: Int, resolved: Boolean): LyngSocketAddress =
+    LyngSocketAddress(
+        host = hostAddress ?: hostName ?: "0.0.0.0",
+        port = port,
+        ipVersion = when (this) {
+            is Inet6Address -> LyngIpVersion.IPV6
+            else -> LyngIpVersion.IPV4
+        },
+        resolved = resolved,
+    )

lyngio/src/androidMain/kotlin/net/sergeych/lyngio/ws/PlatformAndroid.kt

@@ -0,0 +1,5 @@
+package net.sergeych.lyngio.ws
+
+import io.ktor.client.engine.cio.CIO
+
+actual fun getSystemWsEngine(): LyngWsEngine = createKtorWsEngine(CIO)

lyngio/src/commonMain/kotlin/net/sergeych/lyng/io/http/LyngHttpModule.kt

@@ -0,0 +1,390 @@
+/*
+ * Copyright 2026 Sergey S. Chernov real.sergeych@gmail.com
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package net.sergeych.lyng.io.http
+
+import net.sergeych.lyng.ModuleScope
+import net.sergeych.lyng.Scope
+import net.sergeych.lyng.ScopeFacade
+import net.sergeych.lyng.Source
+import net.sergeych.lyng.obj.Obj
+import net.sergeych.lyng.obj.ObjBool
+import net.sergeych.lyng.obj.ObjBuffer
+import net.sergeych.lyng.obj.ObjClass
+import net.sergeych.lyng.obj.ObjImmutableMap
+import net.sergeych.lyng.obj.ObjInt
+import net.sergeych.lyng.obj.ObjList
+import net.sergeych.lyng.obj.ObjMap
+import net.sergeych.lyng.obj.ObjMapEntry
+import net.sergeych.lyng.obj.ObjNull
+import net.sergeych.lyng.obj.ObjString
+import net.sergeych.lyng.obj.ObjVoid
+import net.sergeych.lyng.obj.requiredArg
+import net.sergeych.lyng.obj.thisAs
+import net.sergeych.lyng.pacman.ImportManager
+import net.sergeych.lyng.raiseIllegalOperation
+import net.sergeych.lyng.requireNoArgs
+import net.sergeych.lyng.requireScope
+import net.sergeych.lyngio.http.LyngHttpRequest
+import net.sergeych.lyngio.http.LyngHttpResponse
+import net.sergeych.lyngio.http.getSystemHttpEngine
+import net.sergeych.lyngio.http.security.HttpAccessDeniedException
+import net.sergeych.lyngio.http.security.HttpAccessOp
+import net.sergeych.lyngio.http.security.HttpAccessPolicy
+import net.sergeych.lyngio.stdlib_included.httpLyng
+
+private const val HTTP_MODULE_NAME = "lyng.io.http"
+
+fun createHttpModule(policy: HttpAccessPolicy, scope: Scope): Boolean =
+    createHttpModule(policy, scope.importManager)
+
+fun createHttp(policy: HttpAccessPolicy, scope: Scope): Boolean = createHttpModule(policy, scope)
+
+fun createHttpModule(policy: HttpAccessPolicy, manager: ImportManager): Boolean {
+    if (manager.packageNames.contains(HTTP_MODULE_NAME)) return false
+    manager.addPackage(HTTP_MODULE_NAME) { module ->
+        buildHttpModule(module, policy)
+    }
+    return true
+}
+
+fun createHttp(policy: HttpAccessPolicy, manager: ImportManager): Boolean = createHttpModule(policy, manager)
+
+private suspend fun buildHttpModule(module: ModuleScope, policy: HttpAccessPolicy) {
+    module.eval(Source(HTTP_MODULE_NAME, httpLyng))
+    val engine = getSystemHttpEngine()
+
+    val headersType = ObjHttpHeaders.type
+    val requestType = ObjHttpRequest.type
+    val responseType = ObjHttpResponse.type
+
+    val httpType = object : ObjClass("Http") {}
+    httpType.addClassFn("isSupported") {
+        ObjBool(engine.isSupported)
+    }
+    httpType.addClassFn("request") {
+        httpGuard {
+            val req = requiredArg<ObjHttpRequest>(0)
+            val built = req.toRequest(this)
+            policy.require(HttpAccessOp.Request(built.method, built.url))
+            ObjHttpResponse.from(engine.request(built))
+        }
+    }
+    httpType.addClassFn("get") {
+        httpGuard {
+            val url = requiredArg<ObjString>(0).value
+            val headers = parseHeaderEntries(args.list.drop(1))
+            policy.require(HttpAccessOp.Request("GET", url))
+            ObjHttpResponse.from(engine.request(LyngHttpRequest(method = "GET", url = url, headers = headers)))
+        }
+    }
+    httpType.addClassFn("post") {
+        httpGuard {
+            val url = requiredArg<ObjString>(0).value
+            val bodyText = requiredArg<ObjString>(1).value
+            val contentType = args.list.getOrNull(2)?.let { objOrNullToString(this, it) }
+            val headers = parseHeaderEntries(args.list.drop(3)).toMutableMap()
+            if (contentType != null && "Content-Type" !in headers) headers["Content-Type"] = contentType
+            policy.require(HttpAccessOp.Request("POST", url))
+            ObjHttpResponse.from(
+                engine.request(
+                    LyngHttpRequest(method = "POST", url = url, headers = headers, bodyText = bodyText)
+                )
+            )
+        }
+    }
+    httpType.addClassFn("postBytes") {
+        httpGuard {
+            val url = requiredArg<ObjString>(0).value
+            val body = requiredArg<ObjBuffer>(1).byteArray.toByteArray()
+            val contentType = args.list.getOrNull(2)?.let { objOrNullToString(this, it) }
+            val headers = parseHeaderEntries(args.list.drop(3)).toMutableMap()
+            if (contentType != null && "Content-Type" !in headers) headers["Content-Type"] = contentType
+            policy.require(HttpAccessOp.Request("POST", url))
+            ObjHttpResponse.from(
+                engine.request(
+                    LyngHttpRequest(method = "POST", url = url, headers = headers, bodyBytes = body)
+                )
+            )
+        }
+    }
+
+    module.addConst("Http", httpType)
+    module.addConst("HttpHeaders", headersType)
+    module.addConst("HttpRequest", requestType)
+    module.addConst("HttpResponse", responseType)
+}
+
+private suspend inline fun ScopeFacade.httpGuard(crossinline block: suspend () -> Obj): Obj {
+    return try {
+        block()
+    } catch (e: HttpAccessDeniedException) {
+        raiseIllegalOperation(e.reasonDetail ?: "http access denied")
+    } catch (e: Exception) {
+        raiseIllegalOperation(e.message ?: "http error")
+    }
+}
+
+private class ObjHttpHeaders(
+    singleValueHeaders: Map<String, String> = emptyMap(),
+    private val allHeaders: Map<String, List<String>> = emptyMap(),
+) : Obj() {
+    private val entries: LinkedHashMap<Obj, Obj> =
+        LinkedHashMap(singleValueHeaders.entries.associate { ObjString(it.key) to ObjString(it.value) })
+
+    override val objClass: ObjClass
+        get() = type
+
+    override suspend fun getAt(scope: Scope, index: Obj): Obj = findEntry(index)?.value ?: ObjNull
+
+    override suspend fun contains(scope: Scope, other: Obj): Boolean = findEntry(other) != null
+
+    override suspend fun defaultToString(scope: Scope): ObjString {
+        val rendered = buildString {
+            append("HttpHeaders(")
+            var first = true
+            for ((k, v) in entries) {
+                if (!first) append(", ")
+                append(k.toString(scope).value)
+                append(" => ")
+                append(v.toString(scope).value)
+                first = false
+            }
+            append(")")
+        }
+        return ObjString(rendered)
+    }
+
+    companion object {
+        val type = object : ObjClass("HttpHeaders", ObjMap.type) {
+            override suspend fun callOn(scope: Scope): Obj = ObjHttpHeaders()
+        }.apply {
+            addFn("get") {
+                val self = thisAs<ObjHttpHeaders>()
+                val name = requiredArg<ObjString>(0).value
+                self.firstValue(name)?.let(::ObjString) ?: ObjNull
+            }
+            addFn("getAll") {
+                val self = thisAs<ObjHttpHeaders>()
+                val name = requiredArg<ObjString>(0).value
+                ObjList(self.valuesOf(name).map(::ObjString).toMutableList())
+            }
+            addFn("names") {
+                val self = thisAs<ObjHttpHeaders>()
+                ObjList(self.allHeaders.keys.map(::ObjString).toMutableList())
+            }
+            addFn("getOrNull") {
+                val self = thisAs<ObjHttpHeaders>()
+                val name = requiredArg<ObjString>(0).value
+                self.firstValue(name)?.let(::ObjString) ?: ObjNull
+            }
+            addProperty("size", getter = { ObjInt(thisAs<ObjHttpHeaders>().entries.size.toLong()) })
+            addProperty("keys", getter = { ObjList(thisAs<ObjHttpHeaders>().entries.keys.toMutableList()) })
+            addProperty("values", getter = { ObjList(thisAs<ObjHttpHeaders>().entries.values.toMutableList()) })
+            addFn("iterator") {
+                ObjList(
+                    thisAs<ObjHttpHeaders>().entries.map { (k, v) -> ObjMapEntry(k, v) }.toMutableList()
+                ).invokeInstanceMethod(requireScope(), "iterator")
+            }
+        }
+    }
+
+    private fun valuesOf(name: String): List<String> = allHeaders[lookupKey(name)] ?: emptyList()
+
+    private fun firstValue(name: String): String? = valuesOf(name).firstOrNull()
+
+    private fun lookupKey(name: String): String =
+        allHeaders.keys.firstOrNull { it.equals(name, ignoreCase = true) } ?: name
+
+    private fun findEntry(index: Obj): Map.Entry<Obj, Obj>? {
+        if (index is ObjString) {
+            return entries.entries.firstOrNull { (k, _) ->
+                (k as? ObjString)?.value?.equals(index.value, ignoreCase = true) == true
+            }
+        }
+        return entries.entries.firstOrNull { it.key == index }
+    }
+}
+
+private class ObjHttpRequest(
+    var method: String = "GET",
+    var url: String = "",
+    val headers: MutableMap<String, String> = linkedMapOf(),
+    var bodyText: String? = null,
+    var bodyBytes: ByteArray? = null,
+    var timeoutMillis: Long? = null,
+) : Obj() {
+    override val objClass: ObjClass
+        get() = type
+
+    suspend fun toRequest(scope: ScopeFacade): LyngHttpRequest {
+        if (bodyText != null && bodyBytes != null) {
+            scope.raiseIllegalArgument("Only one of bodyText or bodyBytes may be set")
+        }
+        return LyngHttpRequest(
+            method = method,
+            url = url,
+            headers = LinkedHashMap(headers),
+            bodyText = bodyText,
+            bodyBytes = bodyBytes,
+            timeoutMillis = timeoutMillis,
+        )
+    }
+
+    companion object {
+        val type = object : ObjClass("HttpRequest") {
+            override suspend fun callOn(scope: Scope): Obj {
+                if (scope.args.list.isNotEmpty()) scope.raiseError("HttpRequest() does not accept arguments")
+                return ObjHttpRequest()
+            }
+        }.apply {
+            addProperty("method",
+                getter = { ObjString(thisAs<ObjHttpRequest>().method) },
+                setter = { value ->
+                    thisAs<ObjHttpRequest>().method = objOrNullToString(this, value)
+                        ?: raiseIllegalArgument("method cannot be null")
+                }
+            )
+            addProperty("url",
+                getter = { ObjString(thisAs<ObjHttpRequest>().url) },
+                setter = { value ->
+                    thisAs<ObjHttpRequest>().url = objOrNullToString(this, value)
+                        ?: raiseIllegalArgument("url cannot be null")
+                }
+            )
+            addProperty("headers",
+                getter = { thisAs<ObjHttpRequest>().headers.toObjMap() },
+                setter = { value ->
+                    thisAs<ObjHttpRequest>().headers.clear()
+                    thisAs<ObjHttpRequest>().headers.putAll(mapObjToStrings(this, value))
+                }
+            )
+            addProperty("bodyText",
+                getter = { thisAs<ObjHttpRequest>().bodyText?.let(::ObjString) ?: ObjNull },
+                setter = { value ->
+                    thisAs<ObjHttpRequest>().bodyText = objOrNullToString(this, value)
+                }
+            )
+            addProperty("bodyBytes",
+                getter = { thisAs<ObjHttpRequest>().bodyBytes?.let { ObjBuffer(it.toUByteArray()) } ?: ObjNull },
+                setter = { value ->
+                    thisAs<ObjHttpRequest>().bodyBytes = when (value) {
+                        ObjNull -> null
+                        is ObjBuffer -> value.byteArray.toByteArray()
+                        else -> raiseClassCastError("bodyBytes must be Buffer or null")
+                    }
+                }
+            )
+            addProperty("timeoutMillis",
+                getter = { thisAs<ObjHttpRequest>().timeoutMillis?.let { ObjInt(it) } ?: ObjNull },
+                setter = { value ->
+                    thisAs<ObjHttpRequest>().timeoutMillis = when (value) {
+                        ObjNull -> null
+                        is ObjInt -> value.value
+                        else -> raiseClassCastError("timeoutMillis must be Int or null")
+                    }
+                }
+            )
+        }
+    }
+}
+
+private class ObjHttpResponse(
+    val status: Long,
+    val statusText: String,
+    val headers: ObjHttpHeaders,
+    private val bodyBytes: ByteArray,
+) : Obj() {
+    override val objClass: ObjClass
+        get() = type
+
+    companion object {
+        val type = object : ObjClass("HttpResponse") {
+            override suspend fun callOn(scope: Scope): Obj {
+                scope.raiseError("HttpResponse cannot be created directly")
+            }
+        }.apply {
+            addProperty("status", getter = { ObjInt(thisAs<ObjHttpResponse>().status) })
+            addProperty("statusText", getter = { ObjString(thisAs<ObjHttpResponse>().statusText) })
+            addProperty("headers", getter = { thisAs<ObjHttpResponse>().headers })
+            addFn("text") {
+                ObjString(thisAs<ObjHttpResponse>().bodyBytes.decodeToString())
+            }
+            addFn("bytes") {
+                ObjBuffer(thisAs<ObjHttpResponse>().bodyBytes.toUByteArray())
+            }
+        }
+
+        fun from(response: LyngHttpResponse): ObjHttpResponse {
+            val single = linkedMapOf<String, String>()
+            response.headers.forEach { (name, values) ->
+                if (values.isNotEmpty() && !single.containsKey(name)) {
+                    single[name] = values.first()
+                }
+            }
+            return ObjHttpResponse(
+                status = response.status.toLong(),
+                statusText = response.statusText,
+                headers = ObjHttpHeaders(singleValueHeaders = single, allHeaders = response.headers),
+                bodyBytes = response.bodyBytes,
+            )
+        }
+    }
+}
+
+private suspend fun ScopeFacade.parseHeaderEntries(values: List<Obj>): Map<String, String> {
+    val out = linkedMapOf<String, String>()
+    values.forEach { value ->
+        when (value) {
+            is ObjMapEntry -> {
+                out[toStringOf(value.key).value] = toStringOf(value.value).value
+            }
+            else -> {
+                if (!value.isInstanceOf(net.sergeych.lyng.obj.ObjArray)) {
+                    raiseIllegalArgument("headers entries must be MapEntry or [key, value]")
+                }
+                val size = (value.invokeInstanceMethod(requireScope(), "size") as ObjInt).value.toInt()
+                if (size != 2) {
+                    raiseIllegalArgument("header entry array must contain exactly 2 items")
+                }
+                out[toStringOf(value.getAt(requireScope(), ObjInt.Zero)).value] =
+                    toStringOf(value.getAt(requireScope(), ObjInt.One)).value
+            }
+        }
+    }
+    return out
+}
+
+private suspend fun mapObjToStrings(scope: ScopeFacade, value: Obj): MutableMap<String, String> {
+    val entries = when (value) {
+        is ObjMap -> value.map
+        is ObjImmutableMap -> value.map
+        ObjNull -> return linkedMapOf()
+        else -> scope.raiseClassCastError("headers must be Map<String, String>")
+    }
+    return entries.entries.associateTo(linkedMapOf()) { (k, v) ->
+        scope.toStringOf(k).value to scope.toStringOf(v).value
+    }
+}
+
+private suspend fun objOrNullToString(scope: ScopeFacade, value: Obj): String? = when (value) {
+    ObjNull -> null
+    else -> scope.toStringOf(value).value
+}
+
+private fun Map<String, String>.toObjMap(): ObjMap =
+    ObjMap(entries.associate { ObjString(it.key) to ObjString(it.value) }.toMutableMap())

lyngio/src/commonMain/kotlin/net/sergeych/lyng/io/net/LyngNetModule.kt

@@ -0,0 +1,376 @@
+/*
+ * Copyright 2026 Sergey S. Chernov real.sergeych@gmail.com
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package net.sergeych.lyng.io.net
+
+import net.sergeych.lyng.ModuleScope
+import net.sergeych.lyng.Scope
+import net.sergeych.lyng.ScopeFacade
+import net.sergeych.lyng.Source
+import net.sergeych.lyng.obj.Obj
+import net.sergeych.lyng.obj.ObjBool
+import net.sergeych.lyng.obj.ObjBuffer
+import net.sergeych.lyng.obj.ObjClass
+import net.sergeych.lyng.obj.ObjInt
+import net.sergeych.lyng.obj.ObjList
+import net.sergeych.lyng.obj.ObjNull
+import net.sergeych.lyng.obj.ObjString
+import net.sergeych.lyng.obj.ObjVoid
+import net.sergeych.lyng.obj.requiredArg
+import net.sergeych.lyng.obj.thisAs
+import net.sergeych.lyng.pacman.ImportManager
+import net.sergeych.lyng.raiseIllegalOperation
+import net.sergeych.lyng.requireNoArgs
+import net.sergeych.lyngio.net.LyngDatagram
+import net.sergeych.lyngio.net.LyngIpVersion
+import net.sergeych.lyngio.net.LyngNetEngine
+import net.sergeych.lyngio.net.LyngSocketAddress
+import net.sergeych.lyngio.net.LyngTcpServer
+import net.sergeych.lyngio.net.LyngTcpSocket
+import net.sergeych.lyngio.net.LyngUdpSocket
+import net.sergeych.lyngio.net.getSystemNetEngine
+import net.sergeych.lyngio.net.security.NetAccessDeniedException
+import net.sergeych.lyngio.net.security.NetAccessOp
+import net.sergeych.lyngio.net.security.NetAccessPolicy
+import net.sergeych.lyngio.stdlib_included.netLyng
+
+private const val NET_MODULE_NAME = "lyng.io.net"
+
+fun createNetModule(policy: NetAccessPolicy, scope: Scope): Boolean =
+    createNetModule(policy, scope.importManager)
+
+fun createNet(policy: NetAccessPolicy, scope: Scope): Boolean = createNetModule(policy, scope)
+
+fun createNetModule(policy: NetAccessPolicy, manager: ImportManager): Boolean {
+    if (manager.packageNames.contains(NET_MODULE_NAME)) return false
+    manager.addPackage(NET_MODULE_NAME) { module ->
+        buildNetModule(module, policy)
+    }
+    return true
+}
+
+fun createNet(policy: NetAccessPolicy, manager: ImportManager): Boolean = createNetModule(policy, manager)
+
+private suspend fun buildNetModule(module: ModuleScope, policy: NetAccessPolicy) {
+    module.eval(Source(NET_MODULE_NAME, netLyng))
+    val engine = getSystemNetEngine()
+    val enumValues = NetEnumValues.load(module)
+
+    val netType = object : ObjClass("Net") {}
+    netType.addClassFn("isSupported") { ObjBool(engine.isSupported) }
+    netType.addClassFn("isTcpAvailable") { ObjBool(engine.isTcpAvailable) }
+    netType.addClassFn("isTcpServerAvailable") { ObjBool(engine.isTcpServerAvailable) }
+    netType.addClassFn("isUdpAvailable") { ObjBool(engine.isUdpAvailable) }
+    netType.addClassFn("resolve") {
+        netGuard {
+            val host = requiredArg<ObjString>(0).value
+            val port = requirePort(requiredArg<ObjInt>(1).value)
+            policy.require(NetAccessOp.Resolve(host, port))
+            ObjList(engine.resolve(host, port).map { ObjSocketAddress(it, enumValues) }.toMutableList())
+        }
+    }
+    netType.addClassFn("tcpConnect") {
+        netGuard {
+            val host = requiredArg<ObjString>(0).value
+            val port = requirePort(requiredArg<ObjInt>(1).value)
+            val timeoutMillis = args.list.getOrNull(2)?.let { objOrNullToLong(this, it, "timeoutMillis") }
+            val noDelay = args.list.getOrNull(3)?.let { objToBool(this, it, "noDelay") } ?: true
+            policy.require(NetAccessOp.TcpConnect(host, port))
+            ObjTcpSocket(engine.tcpConnect(host, port, timeoutMillis, noDelay), enumValues)
+        }
+    }
+    netType.addClassFn("tcpListen") {
+        netGuard {
+            val port = requirePort(requiredArg<ObjInt>(0).value)
+            val host = args.list.getOrNull(1)?.let { objOrNullToString(this, it, "host") }
+            val backlog = args.list.getOrNull(2)?.let { objToInt(this, it, "backlog") } ?: 128
+            requirePositive(backlog, "backlog")
+            val reuseAddress = args.list.getOrNull(3)?.let { objToBool(this, it, "reuseAddress") } ?: true
+            policy.require(NetAccessOp.TcpListen(host, port, backlog))
+            ObjTcpServer(engine.tcpListen(host, port, backlog, reuseAddress), enumValues)
+        }
+    }
+    netType.addClassFn("udpBind") {
+        netGuard {
+            val port = args.list.getOrNull(0)?.let { objToInt(this, it, "port") } ?: 0
+            requirePort(port)
+            val host = args.list.getOrNull(1)?.let { objOrNullToString(this, it, "host") }
+            val reuseAddress = args.list.getOrNull(2)?.let { objToBool(this, it, "reuseAddress") } ?: true
+            policy.require(NetAccessOp.UdpBind(host, port))
+            ObjUdpSocket(engine.udpBind(host, port, reuseAddress), enumValues)
+        }
+    }
+
+    module.addConst("Net", netType)
+    module.addConst("SocketAddress", ObjSocketAddress.type(enumValues))
+    module.addConst("Datagram", ObjDatagram.type(enumValues))
+    module.addConst("TcpSocket", ObjTcpSocket.type(enumValues))
+    module.addConst("TcpServer", ObjTcpServer.type(enumValues))
+    module.addConst("UdpSocket", ObjUdpSocket.type(enumValues))
+}
+
+private suspend inline fun ScopeFacade.netGuard(crossinline block: suspend () -> Obj): Obj {
+    return try {
+        block()
+    } catch (e: NetAccessDeniedException) {
+        raiseIllegalOperation(e.reasonDetail ?: "network access denied")
+    } catch (e: Exception) {
+        raiseIllegalOperation(e.message ?: "network error")
+    }
+}
+
+private class NetEnumValues(
+    val ipv4: Obj,
+    val ipv6: Obj,
+) {
+    fun of(version: LyngIpVersion): Obj = when (version) {
+        LyngIpVersion.IPV4 -> ipv4
+        LyngIpVersion.IPV6 -> ipv6
+    }
+
+    companion object {
+        suspend fun load(module: ModuleScope): NetEnumValues {
+            val ipVersionClass = module["IpVersion"]?.value as? ObjClass
+                ?: error("lyng.io.net.IpVersion is missing after declaration load")
+            return NetEnumValues(
+                ipv4 = ipVersionClass.readField(module, "IPV4").value,
+                ipv6 = ipVersionClass.readField(module, "IPV6").value,
+            )
+        }
+    }
+}
+
+private class ObjSocketAddress(
+    private val address: LyngSocketAddress,
+    private val enumValues: NetEnumValues,
+) : Obj() {
+    override val objClass: ObjClass
+        get() = type(enumValues)
+
+    override suspend fun defaultToString(scope: Scope): ObjString = ObjString(renderAddress(address))
+
+    companion object {
+        private val types = mutableMapOf<NetEnumValues, ObjClass>()
+
+        fun type(enumValues: NetEnumValues): ObjClass =
+            types.getOrPut(enumValues) {
+                object : ObjClass("SocketAddress") {
+                    override suspend fun callOn(scope: Scope): Obj {
+                        scope.raiseError("SocketAddress cannot be created directly")
+                    }
+                }.apply {
+                    addProperty("host", getter = { ObjString(thisAs<ObjSocketAddress>().address.host) })
+                    addProperty("port", getter = { ObjInt(thisAs<ObjSocketAddress>().address.port.toLong()) })
+                    addProperty("ipVersion", getter = { enumValues.of(thisAs<ObjSocketAddress>().address.ipVersion) })
+                    addProperty("resolved", getter = { ObjBool(thisAs<ObjSocketAddress>().address.resolved) })
+                    addFn("toString") { ObjString(renderAddress(thisAs<ObjSocketAddress>().address)) }
+                }
+            }
+    }
+}
+
+private class ObjDatagram(
+    private val datagram: LyngDatagram,
+    private val enumValues: NetEnumValues,
+) : Obj() {
+    override val objClass: ObjClass
+        get() = type(enumValues)
+
+    companion object {
+        private val types = mutableMapOf<NetEnumValues, ObjClass>()
+
+        fun type(enumValues: NetEnumValues): ObjClass =
+            types.getOrPut(enumValues) {
+                object : ObjClass("Datagram") {
+                    override suspend fun callOn(scope: Scope): Obj {
+                        scope.raiseError("Datagram cannot be created directly")
+                    }
+                }.apply {
+                    addProperty("data", getter = {
+                        ObjBuffer(thisAs<ObjDatagram>().datagram.data.toUByteArray())
+                    })
+                    addProperty("address", getter = {
+                        ObjSocketAddress(thisAs<ObjDatagram>().datagram.address, enumValues)
+                    })
+                }
+            }
+    }
+}
+
+private class ObjTcpSocket(
+    private val socket: LyngTcpSocket,
+    private val enumValues: NetEnumValues,
+) : Obj() {
+    override val objClass: ObjClass
+        get() = type(enumValues)
+
+    companion object {
+        private val types = mutableMapOf<NetEnumValues, ObjClass>()
+
+        fun type(enumValues: NetEnumValues): ObjClass =
+            types.getOrPut(enumValues) {
+                object : ObjClass("TcpSocket") {
+                    override suspend fun callOn(scope: Scope): Obj {
+                        scope.raiseError("TcpSocket cannot be created directly")
+                    }
+                }.apply {
+                    addFn("isOpen") { ObjBool(thisAs<ObjTcpSocket>().socket.isOpen()) }
+                    addFn("localAddress") { ObjSocketAddress(thisAs<ObjTcpSocket>().socket.localAddress(), enumValues) }
+                    addFn("remoteAddress") { ObjSocketAddress(thisAs<ObjTcpSocket>().socket.remoteAddress(), enumValues) }
+                    addFn("read") {
+                        val maxBytes = args.list.getOrNull(0)?.let { objToInt(this, it, "maxBytes") } ?: 65536
+                        requirePositive(maxBytes, "maxBytes")
+                        thisAs<ObjTcpSocket>().socket.read(maxBytes)?.let { ObjBuffer(it.toUByteArray()) } ?: ObjNull
+                    }
+                    addFn("readLine") {
+                        thisAs<ObjTcpSocket>().socket.readLine()?.let(::ObjString) ?: ObjNull
+                    }
+                    addFn("write") {
+                        val data = requiredArg<ObjBuffer>(0).byteArray.toByteArray()
+                        thisAs<ObjTcpSocket>().socket.write(data)
+                        ObjVoid
+                    }
+                    addFn("writeUtf8") {
+                        val text = requiredArg<ObjString>(0).value
+                        thisAs<ObjTcpSocket>().socket.writeUtf8(text)
+                        ObjVoid
+                    }
+                    addFn("flush") {
+                        requireNoArgs()
+                        thisAs<ObjTcpSocket>().socket.flush()
+                        ObjVoid
+                    }
+                    addFn("close") {
+                        requireNoArgs()
+                        thisAs<ObjTcpSocket>().socket.close()
+                        ObjVoid
+                    }
+                }
+            }
+    }
+}
+
+private class ObjTcpServer(
+    private val server: LyngTcpServer,
+    private val enumValues: NetEnumValues,
+) : Obj() {
+    override val objClass: ObjClass
+        get() = type(enumValues)
+
+    companion object {
+        private val types = mutableMapOf<NetEnumValues, ObjClass>()
+
+        fun type(enumValues: NetEnumValues): ObjClass =
+            types.getOrPut(enumValues) {
+                object : ObjClass("TcpServer") {
+                    override suspend fun callOn(scope: Scope): Obj {
+                        scope.raiseError("TcpServer cannot be created directly")
+                    }
+                }.apply {
+                    addFn("isOpen") { ObjBool(thisAs<ObjTcpServer>().server.isOpen()) }
+                    addFn("localAddress") { ObjSocketAddress(thisAs<ObjTcpServer>().server.localAddress(), enumValues) }
+                    addFn("accept") {
+                        ObjTcpSocket(thisAs<ObjTcpServer>().server.accept(), enumValues)
+                    }
+                    addFn("close") {
+                        requireNoArgs()
+                        thisAs<ObjTcpServer>().server.close()
+                        ObjVoid
+                    }
+                }
+            }
+    }
+}
+
+private class ObjUdpSocket(
+    private val socket: LyngUdpSocket,
+    private val enumValues: NetEnumValues,
+) : Obj() {
+    override val objClass: ObjClass
+        get() = type(enumValues)
+
+    companion object {
+        private val types = mutableMapOf<NetEnumValues, ObjClass>()
+
+        fun type(enumValues: NetEnumValues): ObjClass =
+            types.getOrPut(enumValues) {
+                object : ObjClass("UdpSocket") {
+                    override suspend fun callOn(scope: Scope): Obj {
+                        scope.raiseError("UdpSocket cannot be created directly")
+                    }
+                }.apply {
+                    addFn("isOpen") { ObjBool(thisAs<ObjUdpSocket>().socket.isOpen()) }
+                    addFn("localAddress") { ObjSocketAddress(thisAs<ObjUdpSocket>().socket.localAddress(), enumValues) }
+                    addFn("receive") {
+                        val maxBytes = args.list.getOrNull(0)?.let { objToInt(this, it, "maxBytes") } ?: 65536
+                        requirePositive(maxBytes, "maxBytes")
+                        thisAs<ObjUdpSocket>().socket.receive(maxBytes)?.let { ObjDatagram(it, enumValues) } ?: ObjNull
+                    }
+                    addFn("send") {
+                        val data = requiredArg<ObjBuffer>(0).byteArray.toByteArray()
+                        val host = requiredArg<ObjString>(1).value
+                        val port = requirePort(requiredArg<ObjInt>(2).value)
+                        thisAs<ObjUdpSocket>().socket.send(data, host, port)
+                        ObjVoid
+                    }
+                    addFn("close") {
+                        requireNoArgs()
+                        thisAs<ObjUdpSocket>().socket.close()
+                        ObjVoid
+                    }
+                }
+            }
+    }
+}
+
+private fun renderAddress(address: LyngSocketAddress): String =
+    if (address.ipVersion == LyngIpVersion.IPV6) "[${address.host}]:${address.port}" else "${address.host}:${address.port}"
+
+private fun ScopeFacade.requirePort(value: Long): Int {
+    if (value !in 0..65535) raiseIllegalArgument("port must be in 0..65535")
+    return value.toInt()
+}
+
+private fun ScopeFacade.requirePort(value: Int): Int {
+    if (value !in 0..65535) raiseIllegalArgument("port must be in 0..65535")
+    return value
+}
+
+private fun ScopeFacade.requirePositive(value: Int, name: String) {
+    if (value <= 0) raiseIllegalArgument("$name must be positive")
+}
+
+private suspend fun objOrNullToString(scope: ScopeFacade, value: Obj, name: String): String? = when (value) {
+    ObjNull -> null
+    else -> scope.toStringOf(value).value
+}
+
+private fun objToInt(scope: ScopeFacade, value: Obj, name: String): Int = when (value) {
+    is ObjInt -> value.value.toInt()
+    else -> scope.raiseClassCastError("$name must be Int")
+}
+
+private fun objToBool(scope: ScopeFacade, value: Obj, name: String): Boolean = when (value) {
+    is ObjBool -> value.value
+    else -> scope.raiseClassCastError("$name must be Bool")
+}
+
+private fun objOrNullToLong(scope: ScopeFacade, value: Obj, name: String): Long? = when (value) {
+    ObjNull -> null
+    is ObjInt -> value.value
+    else -> scope.raiseClassCastError("$name must be Int or null")
+}

lyngio/src/commonMain/kotlin/net/sergeych/lyng/io/ws/LyngWsModule.kt

@@ -0,0 +1,199 @@
+/*
+ * Copyright 2026 Sergey S. Chernov real.sergeych@gmail.com
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package net.sergeych.lyng.io.ws
+
+import net.sergeych.lyng.ModuleScope
+import net.sergeych.lyng.Scope
+import net.sergeych.lyng.ScopeFacade
+import net.sergeych.lyng.Source
+import net.sergeych.lyng.obj.Obj
+import net.sergeych.lyng.obj.ObjBool
+import net.sergeych.lyng.obj.ObjBuffer
+import net.sergeych.lyng.obj.ObjClass
+import net.sergeych.lyng.obj.ObjInt
+import net.sergeych.lyng.obj.ObjMapEntry
+import net.sergeych.lyng.obj.ObjNull
+import net.sergeych.lyng.obj.ObjString
+import net.sergeych.lyng.obj.ObjVoid
+import net.sergeych.lyng.obj.requiredArg
+import net.sergeych.lyng.obj.thisAs
+import net.sergeych.lyng.pacman.ImportManager
+import net.sergeych.lyng.raiseIllegalOperation
+import net.sergeych.lyng.requireNoArgs
+import net.sergeych.lyng.requireScope
+import net.sergeych.lyngio.stdlib_included.wsLyng
+import net.sergeych.lyngio.ws.LyngWsEngine
+import net.sergeych.lyngio.ws.LyngWsMessage
+import net.sergeych.lyngio.ws.LyngWsSession
+import net.sergeych.lyngio.ws.getSystemWsEngine
+import net.sergeych.lyngio.ws.security.WsAccessDeniedException
+import net.sergeych.lyngio.ws.security.WsAccessOp
+import net.sergeych.lyngio.ws.security.WsAccessPolicy
+
+private const val WS_MODULE_NAME = "lyng.io.ws"
+
+fun createWsModule(policy: WsAccessPolicy, scope: Scope): Boolean =
+    createWsModule(policy, scope.importManager)
+
+fun createWs(policy: WsAccessPolicy, scope: Scope): Boolean = createWsModule(policy, scope)
+
+fun createWsModule(policy: WsAccessPolicy, manager: ImportManager): Boolean {
+    if (manager.packageNames.contains(WS_MODULE_NAME)) return false
+    manager.addPackage(WS_MODULE_NAME) { module ->
+        buildWsModule(module, policy)
+    }
+    return true
+}
+
+fun createWs(policy: WsAccessPolicy, manager: ImportManager): Boolean = createWsModule(policy, manager)
+
+private suspend fun buildWsModule(module: ModuleScope, policy: WsAccessPolicy) {
+    module.eval(Source(WS_MODULE_NAME, wsLyng))
+    val engine = getSystemWsEngine()
+
+    val wsType = object : ObjClass("Ws") {}
+    wsType.addClassFn("isSupported") { ObjBool(engine.isSupported) }
+    wsType.addClassFn("connect") {
+        wsGuard {
+            val url = requiredArg<ObjString>(0).value
+            val headers = parseHeaderEntries(args.list.drop(1))
+            policy.require(WsAccessOp.Connect(url))
+            ObjWsSession(url, engine.connect(url, headers), policy)
+        }
+    }
+
+    module.addConst("Ws", wsType)
+    module.addConst("WsMessage", ObjWsMessage.type)
+    module.addConst("WsSession", ObjWsSession.type)
+}
+
+private suspend inline fun ScopeFacade.wsGuard(crossinline block: suspend () -> Obj): Obj {
+    return try {
+        block()
+    } catch (e: WsAccessDeniedException) {
+        raiseIllegalOperation(e.reasonDetail ?: "websocket access denied")
+    } catch (e: Exception) {
+        raiseIllegalOperation(e.message ?: "websocket error")
+    }
+}
+
+private class ObjWsMessage(
+    private val message: LyngWsMessage,
+) : Obj() {
+    override val objClass: ObjClass
+        get() = type
+
+    companion object {
+        val type = object : ObjClass("WsMessage") {
+            override suspend fun callOn(scope: Scope): Obj {
+                scope.raiseError("WsMessage cannot be created directly")
+            }
+        }.apply {
+            addProperty("isText", getter = { ObjBool(thisAs<ObjWsMessage>().message.isText) })
+            addProperty("text", getter = {
+                thisAs<ObjWsMessage>().message.text?.let(::ObjString) ?: ObjNull
+            })
+            addProperty("data", getter = {
+                thisAs<ObjWsMessage>().message.data?.let { ObjBuffer(it.toUByteArray()) } ?: ObjNull
+            })
+        }
+    }
+}
+
+private class ObjWsSession(
+    private val targetUrl: String,
+    private val session: LyngWsSession,
+    private val policy: WsAccessPolicy,
+) : Obj() {
+    override val objClass: ObjClass
+        get() = type
+
+    companion object {
+        val type = object : ObjClass("WsSession") {
+            override suspend fun callOn(scope: Scope): Obj {
+                scope.raiseError("WsSession cannot be created directly")
+            }
+        }.apply {
+            addFn("isOpen") {
+                ObjBool(thisAs<ObjWsSession>().session.isOpen())
+            }
+            addFn("url") {
+                ObjString(thisAs<ObjWsSession>().targetUrl)
+            }
+            addFn("sendText") {
+                val self = thisAs<ObjWsSession>()
+                val text = requiredArg<ObjString>(0).value
+                self.policy.require(WsAccessOp.Send(self.targetUrl, text.encodeToByteArray().size, isText = true))
+                self.session.sendText(text)
+                ObjVoid
+            }
+            addFn("sendBytes") {
+                val self = thisAs<ObjWsSession>()
+                val data = requiredArg<ObjBuffer>(0).byteArray.toByteArray()
+                self.policy.require(WsAccessOp.Send(self.targetUrl, data.size, isText = false))
+                self.session.sendBytes(data)
+                ObjVoid
+            }
+            addFn("receive") {
+                val self = thisAs<ObjWsSession>()
+                self.policy.require(WsAccessOp.Receive(self.targetUrl))
+                self.session.receive()?.let(::ObjWsMessage) ?: ObjNull
+            }
+            addFn("close") {
+                val self = thisAs<ObjWsSession>()
+                val code = args.list.getOrNull(0)?.let { objToInt(this, it, "code") } ?: 1000
+                val reason = args.list.getOrNull(1)?.let { objOrNullToString(this, it, "reason") } ?: ""
+                self.session.close(code, reason)
+                ObjVoid
+            }
+        }
+    }
+}
+
+private suspend fun ScopeFacade.parseHeaderEntries(values: List<Obj>): Map<String, String> {
+    val out = linkedMapOf<String, String>()
+    values.forEach { value ->
+        when (value) {
+            is ObjMapEntry -> {
+                out[toStringOf(value.key).value] = toStringOf(value.value).value
+            }
+            else -> {
+                if (!value.isInstanceOf(net.sergeych.lyng.obj.ObjArray)) {
+                    raiseIllegalArgument("headers entries must be MapEntry or [key, value]")
+                }
+                val size = (value.invokeInstanceMethod(requireScope(), "size") as ObjInt).value.toInt()
+                if (size != 2) {
+                    raiseIllegalArgument("header entry array must contain exactly 2 items")
+                }
+                out[toStringOf(value.getAt(requireScope(), ObjInt.Zero)).value] =
+                    toStringOf(value.getAt(requireScope(), ObjInt.One)).value
+            }
+        }
+    }
+    return out
+}
+
+private suspend fun objOrNullToString(scope: ScopeFacade, value: Obj, name: String): String? = when (value) {
+    ObjNull -> null
+    else -> scope.toStringOf(value).value
+}
+
+private fun objToInt(scope: ScopeFacade, value: Obj, name: String): Int = when (value) {
+    is ObjInt -> value.value.toInt()
+    else -> scope.raiseClassCastError("$name must be Int")
+}

lyngio/src/commonMain/kotlin/net/sergeych/lyngio/http/KtorHttpEngine.kt

@@ -0,0 +1,61 @@
+package net.sergeych.lyngio.http
+
+import io.ktor.client.HttpClient
+import io.ktor.client.call.body
+import io.ktor.client.engine.HttpClientEngineConfig
+import io.ktor.client.engine.HttpClientEngineFactory
+import io.ktor.client.plugins.timeout
+import io.ktor.client.request.HttpRequestBuilder
+import io.ktor.client.request.request
+import io.ktor.client.request.setBody
+import io.ktor.http.HttpMethod
+import io.ktor.http.headers
+import io.ktor.http.takeFrom
+
+internal fun createKtorHttpEngine(
+    engineFactory: HttpClientEngineFactory<HttpClientEngineConfig>,
+): LyngHttpEngine = KtorLyngHttpEngine(engineFactory)
+
+private class KtorLyngHttpEngine(
+    engineFactory: HttpClientEngineFactory<HttpClientEngineConfig>,
+) : LyngHttpEngine {
+    private val clientResult = runCatching {
+        HttpClient(engineFactory) {
+            expectSuccess = false
+        }
+    }
+
+    override val isSupported: Boolean
+        get() = clientResult.isSuccess
+
+    override suspend fun request(request: LyngHttpRequest): LyngHttpResponse {
+        val httpClient = clientResult.getOrElse {
+            throw UnsupportedOperationException(it.message ?: "HTTP client is not supported")
+        }
+
+        val response = httpClient.request {
+            applyRequest(request)
+        }
+        return LyngHttpResponse(
+            status = response.status.value,
+            statusText = response.status.description,
+            headers = response.headers.entries().associate { it.key to it.value.toList() },
+            bodyBytes = response.body<ByteArray>(),
+        )
+    }
+
+    private fun HttpRequestBuilder.applyRequest(request: LyngHttpRequest) {
+        method = HttpMethod.parse(request.method.uppercase())
+        url.takeFrom(request.url)
+        headers {
+            request.headers.forEach { (name, value) -> append(name, value) }
+        }
+        request.timeoutMillis?.let { timeout { requestTimeoutMillis = it } }
+        when {
+            request.bodyBytes != null && request.bodyText != null ->
+                throw IllegalArgumentException("Only one of bodyText or bodyBytes may be set")
+            request.bodyBytes != null -> setBody(request.bodyBytes)
+            request.bodyText != null -> setBody(request.bodyText)
+        }
+    }
+}

lyngio/src/commonMain/kotlin/net/sergeych/lyngio/http/LyngHttp.kt

@@ -0,0 +1,49 @@
+/*
+ * Copyright 2026 Sergey S. Chernov real.sergeych@gmail.com
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package net.sergeych.lyngio.http
+
+data class LyngHttpRequest(
+    val method: String,
+    val url: String,
+    val headers: Map<String, String> = emptyMap(),
+    val bodyText: String? = null,
+    val bodyBytes: ByteArray? = null,
+    val timeoutMillis: Long? = null,
+)
+
+data class LyngHttpResponse(
+    val status: Int,
+    val statusText: String,
+    val headers: Map<String, List<String>>,
+    val bodyBytes: ByteArray,
+)
+
+interface LyngHttpEngine {
+    val isSupported: Boolean
+    suspend fun request(request: LyngHttpRequest): LyngHttpResponse
+}
+
+internal object UnsupportedHttpEngine : LyngHttpEngine {
+    override val isSupported: Boolean = false
+
+    override suspend fun request(request: LyngHttpRequest): LyngHttpResponse {
+        throw UnsupportedOperationException("HTTP client is not supported on this runtime")
+    }
+}
+
+expect fun getSystemHttpEngine(): LyngHttpEngine

lyngio/src/commonMain/kotlin/net/sergeych/lyngio/http/security/HttpAccessPolicy.kt

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2026 Sergey S. Chernov real.sergeych@gmail.com
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package net.sergeych.lyngio.http.security
+
+import net.sergeych.lyngio.fs.security.AccessContext
+import net.sergeych.lyngio.fs.security.AccessDecision
+import net.sergeych.lyngio.fs.security.Decision
+
+sealed interface HttpAccessOp {
+    data class Request(val method: String, val url: String) : HttpAccessOp
+}
+
+class HttpAccessDeniedException(
+    val op: HttpAccessOp,
+    val reasonDetail: String? = null,
+) : IllegalStateException("HTTP access denied for $op" + (reasonDetail?.let { ": $it" } ?: ""))
+
+interface HttpAccessPolicy {
+    suspend fun check(op: HttpAccessOp, ctx: AccessContext = AccessContext()): AccessDecision
+
+    suspend fun require(op: HttpAccessOp, ctx: AccessContext = AccessContext()) {
+        val res = check(op, ctx)
+        if (!res.isAllowed()) throw HttpAccessDeniedException(op, res.reason)
+    }
+}
+
+object PermitAllHttpAccessPolicy : HttpAccessPolicy {
+    override suspend fun check(op: HttpAccessOp, ctx: AccessContext): AccessDecision =
+        AccessDecision(Decision.Allow)
+}

lyngio/src/commonMain/kotlin/net/sergeych/lyngio/net/LyngNet.kt

@@ -0,0 +1,99 @@
+/*
+ * Copyright 2026 Sergey S. Chernov real.sergeych@gmail.com
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package net.sergeych.lyngio.net
+
+enum class LyngIpVersion {
+    IPV4,
+    IPV6,
+}
+
+data class LyngSocketAddress(
+    val host: String,
+    val port: Int,
+    val ipVersion: LyngIpVersion,
+    val resolved: Boolean,
+)
+
+data class LyngDatagram(
+    val data: ByteArray,
+    val address: LyngSocketAddress,
+)
+
+interface LyngTcpSocket {
+    fun isOpen(): Boolean
+    fun localAddress(): LyngSocketAddress
+    fun remoteAddress(): LyngSocketAddress
+    suspend fun read(maxBytes: Int): ByteArray?
+    suspend fun readLine(): String?
+    suspend fun write(data: ByteArray)
+    suspend fun writeUtf8(text: String)
+    suspend fun flush()
+    fun close()
+}
+
+interface LyngTcpServer {
+    fun isOpen(): Boolean
+    fun localAddress(): LyngSocketAddress
+    suspend fun accept(): LyngTcpSocket
+    fun close()
+}
+
+interface LyngUdpSocket {
+    fun isOpen(): Boolean
+    fun localAddress(): LyngSocketAddress
+    suspend fun receive(maxBytes: Int): LyngDatagram?
+    suspend fun send(data: ByteArray, host: String, port: Int)
+    fun close()
+}
+
+interface LyngNetEngine {
+    val isSupported: Boolean
+    val isTcpAvailable: Boolean
+    val isTcpServerAvailable: Boolean
+    val isUdpAvailable: Boolean
+
+    suspend fun resolve(host: String, port: Int): List<LyngSocketAddress>
+    suspend fun tcpConnect(host: String, port: Int, timeoutMillis: Long?, noDelay: Boolean): LyngTcpSocket
+    suspend fun tcpListen(host: String?, port: Int, backlog: Int, reuseAddress: Boolean): LyngTcpServer
+    suspend fun udpBind(host: String?, port: Int, reuseAddress: Boolean): LyngUdpSocket
+}
+
+internal object UnsupportedLyngNetEngine : LyngNetEngine {
+    override val isSupported: Boolean = false
+    override val isTcpAvailable: Boolean = false
+    override val isTcpServerAvailable: Boolean = false
+    override val isUdpAvailable: Boolean = false
+
+    override suspend fun resolve(host: String, port: Int): List<LyngSocketAddress> {
+        throw UnsupportedOperationException("Raw networking is not supported on this runtime")
+    }
+
+    override suspend fun tcpConnect(host: String, port: Int, timeoutMillis: Long?, noDelay: Boolean): LyngTcpSocket {
+        throw UnsupportedOperationException("TCP client sockets are not supported on this runtime")
+    }
+
+    override suspend fun tcpListen(host: String?, port: Int, backlog: Int, reuseAddress: Boolean): LyngTcpServer {
+        throw UnsupportedOperationException("TCP server sockets are not supported on this runtime")
+    }
+
+    override suspend fun udpBind(host: String?, port: Int, reuseAddress: Boolean): LyngUdpSocket {
+        throw UnsupportedOperationException("UDP sockets are not supported on this runtime")
+    }
+}
+
+expect fun getSystemNetEngine(): LyngNetEngine

lyngio/src/commonMain/kotlin/net/sergeych/lyngio/net/security/NetAccessPolicy.kt

@@ -0,0 +1,48 @@
+/*
+ * Copyright 2026 Sergey S. Chernov real.sergeych@gmail.com
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package net.sergeych.lyngio.net.security
+
+import net.sergeych.lyngio.fs.security.AccessContext
+import net.sergeych.lyngio.fs.security.AccessDecision
+import net.sergeych.lyngio.fs.security.Decision
+
+sealed interface NetAccessOp {
+    data class Resolve(val host: String, val port: Int) : NetAccessOp
+    data class TcpConnect(val host: String, val port: Int) : NetAccessOp
+    data class TcpListen(val host: String?, val port: Int, val backlog: Int) : NetAccessOp
+    data class UdpBind(val host: String?, val port: Int) : NetAccessOp
+}
+
+class NetAccessDeniedException(
+    val op: NetAccessOp,
+    val reasonDetail: String? = null,
+) : IllegalStateException("Network access denied for $op" + (reasonDetail?.let { ": $it" } ?: ""))
+
+interface NetAccessPolicy {
+    suspend fun check(op: NetAccessOp, ctx: AccessContext = AccessContext()): AccessDecision
+
+    suspend fun require(op: NetAccessOp, ctx: AccessContext = AccessContext()) {
+        val res = check(op, ctx)
+        if (!res.isAllowed()) throw NetAccessDeniedException(op, res.reason)
+    }
+}
+
+object PermitAllNetAccessPolicy : NetAccessPolicy {
+    override suspend fun check(op: NetAccessOp, ctx: AccessContext): AccessDecision =
+        AccessDecision(Decision.Allow)
+}

lyngio/src/commonMain/kotlin/net/sergeych/lyngio/ws/KtorWsEngine.kt

@@ -0,0 +1,94 @@
+package net.sergeych.lyngio.ws
+
+import io.ktor.client.HttpClient
+import io.ktor.client.engine.HttpClientEngineConfig
+import io.ktor.client.engine.HttpClientEngineFactory
+import io.ktor.client.plugins.websocket.WebSockets
+import io.ktor.client.plugins.websocket.webSocketSession
+import io.ktor.client.request.header
+import io.ktor.client.request.url
+import io.ktor.websocket.CloseReason
+import io.ktor.websocket.DefaultWebSocketSession
+import io.ktor.websocket.Frame
+import io.ktor.websocket.close
+import io.ktor.websocket.readText
+import io.ktor.websocket.send
+import kotlinx.coroutines.channels.ClosedReceiveChannelException
+
+internal fun createKtorWsEngine(
+    engineFactory: HttpClientEngineFactory<HttpClientEngineConfig>,
+): LyngWsEngine = KtorLyngWsEngine(engineFactory)
+
+private class KtorLyngWsEngine(
+    engineFactory: HttpClientEngineFactory<HttpClientEngineConfig>,
+) : LyngWsEngine {
+    private val clientResult = runCatching {
+        HttpClient(engineFactory) {
+            install(WebSockets)
+        }
+    }
+
+    override val isSupported: Boolean
+        get() = clientResult.isSuccess
+
+    override suspend fun connect(url: String, headers: Map<String, String>): LyngWsSession {
+        val client = clientResult.getOrElse {
+            throw UnsupportedOperationException(it.message ?: "WebSocket client is not supported")
+        }
+        val session = client.webSocketSession {
+            url(url)
+            headers.forEach { (name, value) -> header(name, value) }
+        }
+        return KtorLyngWsSession(url, session)
+    }
+}
+
+private class KtorLyngWsSession(
+    private val targetUrl: String,
+    private val session: DefaultWebSocketSession,
+) : LyngWsSession {
+    private var closed = false
+
+    override fun isOpen(): Boolean = !closed
+
+    override fun url(): String = targetUrl
+
+    override suspend fun sendText(text: String) {
+        ensureOpen()
+        session.send(text)
+    }
+
+    override suspend fun sendBytes(data: ByteArray) {
+        ensureOpen()
+        session.send(data)
+    }
+
+    override suspend fun receive(): LyngWsMessage? {
+        if (closed) return null
+        val frame = try {
+            session.incoming.receive()
+        } catch (_: ClosedReceiveChannelException) {
+            closed = true
+            return null
+        }
+        return when (frame) {
+            is Frame.Text -> LyngWsMessage(isText = true, text = frame.readText())
+            is Frame.Binary -> LyngWsMessage(isText = false, data = frame.data.copyOf())
+            is Frame.Close -> {
+                closed = true
+                null
+            }
+            else -> receive()
+        }
+    }
+
+    override suspend fun close(code: Int, reason: String) {
+        if (closed) return
+        closed = true
+        session.close(CloseReason(code.toShort(), reason))
+    }
+
+    private fun ensureOpen() {
+        if (closed) throw IllegalStateException("websocket session is closed")
+    }
+}

lyngio/src/commonMain/kotlin/net/sergeych/lyngio/ws/LyngWs.kt

@@ -0,0 +1,48 @@
+/*
+ * Copyright 2026 Sergey S. Chernov real.sergeych@gmail.com
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package net.sergeych.lyngio.ws
+
+data class LyngWsMessage(
+    val isText: Boolean,
+    val text: String? = null,
+    val data: ByteArray? = null,
+)
+
+interface LyngWsSession {
+    fun isOpen(): Boolean
+    fun url(): String
+    suspend fun sendText(text: String)
+    suspend fun sendBytes(data: ByteArray)
+    suspend fun receive(): LyngWsMessage?
+    suspend fun close(code: Int, reason: String)
+}
+
+interface LyngWsEngine {
+    val isSupported: Boolean
+    suspend fun connect(url: String, headers: Map<String, String>): LyngWsSession
+}
+
+internal object UnsupportedLyngWsEngine : LyngWsEngine {
+    override val isSupported: Boolean = false
+
+    override suspend fun connect(url: String, headers: Map<String, String>): LyngWsSession {
+        throw UnsupportedOperationException("WebSocket client is not supported on this runtime")
+    }
+}
+
+expect fun getSystemWsEngine(): LyngWsEngine

lyngio/src/commonMain/kotlin/net/sergeych/lyngio/ws/security/WsAccessPolicy.kt

@@ -0,0 +1,47 @@
+/*
+ * Copyright 2026 Sergey S. Chernov real.sergeych@gmail.com
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package net.sergeych.lyngio.ws.security
+
+import net.sergeych.lyngio.fs.security.AccessContext
+import net.sergeych.lyngio.fs.security.AccessDecision
+import net.sergeych.lyngio.fs.security.Decision
+
+sealed interface WsAccessOp {
+    data class Connect(val url: String) : WsAccessOp
+    data class Send(val url: String, val bytes: Int, val isText: Boolean) : WsAccessOp
+    data class Receive(val url: String) : WsAccessOp
+}
+
+class WsAccessDeniedException(
+    val op: WsAccessOp,
+    val reasonDetail: String? = null,
+) : IllegalStateException("WebSocket access denied for $op" + (reasonDetail?.let { ": $it" } ?: ""))
+
+interface WsAccessPolicy {
+    suspend fun check(op: WsAccessOp, ctx: AccessContext = AccessContext()): AccessDecision
+
+    suspend fun require(op: WsAccessOp, ctx: AccessContext = AccessContext()) {
+        val res = check(op, ctx)
+        if (!res.isAllowed()) throw WsAccessDeniedException(op, res.reason)
+    }
+}
+
+object PermitAllWsAccessPolicy : WsAccessPolicy {
+    override suspend fun check(op: WsAccessOp, ctx: AccessContext): AccessDecision =
+        AccessDecision(Decision.Allow)
+}

lyngio/src/darwinMain/kotlin/net/sergeych/lyngio/http/PlatformDarwin.kt

@@ -0,0 +1,5 @@
+package net.sergeych.lyngio.http
+
+import io.ktor.client.engine.darwin.Darwin
+
+actual fun getSystemHttpEngine(): LyngHttpEngine = createKtorHttpEngine(Darwin)

lyngio/src/darwinMain/kotlin/net/sergeych/lyngio/net/PlatformDarwin.kt

@@ -0,0 +1,8 @@
+package net.sergeych.lyngio.net
+
+actual fun getSystemNetEngine(): LyngNetEngine = createNativeKtorNetEngine(
+    isSupported = true,
+    isTcpAvailable = true,
+    isTcpServerAvailable = true,
+    isUdpAvailable = true,
+)

lyngio/src/darwinMain/kotlin/net/sergeych/lyngio/ws/PlatformDarwin.kt

@@ -0,0 +1,5 @@
+package net.sergeych.lyngio.ws
+
+import io.ktor.client.engine.darwin.Darwin
+
+actual fun getSystemWsEngine(): LyngWsEngine = createKtorWsEngine(Darwin)

lyngio/src/jsMain/kotlin/net/sergeych/lyngio/http/PlatformJs.kt

@@ -0,0 +1,5 @@
+package net.sergeych.lyngio.http
+
+import io.ktor.client.engine.js.Js
+
+actual fun getSystemHttpEngine(): LyngHttpEngine = createKtorHttpEngine(Js)

lyngio/src/jsMain/kotlin/net/sergeych/lyngio/net/PlatformJs.kt

@@ -0,0 +1,422 @@
+@file:Suppress("UnsafeCastFromDynamic", "SpellCheckingInspection")
+
+package net.sergeych.lyngio.net
+
+import kotlinx.coroutines.channels.Channel
+import kotlinx.coroutines.withTimeout
+import kotlinx.coroutines.withTimeoutOrNull
+import kotlinx.coroutines.suspendCancellableCoroutine
+import kotlin.coroutines.resume
+import kotlin.coroutines.resumeWithException
+import kotlin.js.json
+import org.khronos.webgl.Uint8Array
+
+actual fun getSystemNetEngine(): LyngNetEngine = jsNodeNetEngineOrNull ?: UnsupportedLyngNetEngine
+
+private val jsNodeNetEngineOrNull: LyngNetEngine? by lazy {
+    if (!isNodeRuntime()) return@lazy null
+    val net = requireNodeModule("net") ?: return@lazy null
+    val dgram = requireNodeModule("dgram") ?: return@lazy null
+    val dns = requireNodeModule("dns") ?: return@lazy null
+    JsNodeNetEngine(net, dgram, dns)
+}
+
+private class JsNodeNetEngine(
+    private val netModule: dynamic,
+    private val dgramModule: dynamic,
+    private val dnsModule: dynamic,
+) : LyngNetEngine {
+    override val isSupported: Boolean = true
+    override val isTcpAvailable: Boolean = true
+    override val isTcpServerAvailable: Boolean = true
+    override val isUdpAvailable: Boolean = true
+
+    override suspend fun resolve(host: String, port: Int): List<LyngSocketAddress> {
+        val family = netModule.isIP(host) as Int
+        if (family == 4 || family == 6) {
+            return listOf(
+                LyngSocketAddress(
+                    host = host,
+                    port = port,
+                    ipVersion = if (family == 6) LyngIpVersion.IPV6 else LyngIpVersion.IPV4,
+                    resolved = true,
+                )
+            )
+        }
+        return suspendCancellableCoroutine { cont ->
+            dnsModule.lookup(host, json("all" to true), { error: dynamic, result: dynamic ->
+                if (!cont.isActive) return@lookup
+                if (error != null) {
+                    cont.resumeWithException(IllegalStateException(error.message?.unsafeCast<String>() ?: "DNS lookup failed"))
+                    return@lookup
+                }
+                val addresses = mutableListOf<LyngSocketAddress>()
+                val items = result.unsafeCast<Array<dynamic>>()
+                for (item in items) {
+                    val address = item.address?.unsafeCast<String>() ?: continue
+                    val itemFamily = item.family?.unsafeCast<Int>() ?: if (address.contains(':')) 6 else 4
+                    addresses += LyngSocketAddress(
+                        host = address,
+                        port = port,
+                        ipVersion = if (itemFamily == 6) LyngIpVersion.IPV6 else LyngIpVersion.IPV4,
+                        resolved = true,
+                    )
+                }
+                cont.resume(addresses)
+            })
+        }
+    }
+
+    override suspend fun tcpConnect(
+        host: String,
+        port: Int,
+        timeoutMillis: Long?,
+        noDelay: Boolean,
+    ): LyngTcpSocket {
+        var socket: dynamic = null
+        return try {
+            val connected = suspend {
+                suspendCancellableCoroutine<dynamic> { cont ->
+                    socket = netModule.createConnection(json("host" to host, "port" to port)) {
+                        if (cont.isActive) cont.resume(socket)
+                    }
+                    socket.once("error", { error: dynamic ->
+                        if (cont.isActive) {
+                            cont.resumeWithException(
+                                IllegalStateException(error.message?.unsafeCast<String>() ?: "TCP connect failed")
+                            )
+                        }
+                    })
+                }
+            }
+            val connectedSocket = if (timeoutMillis != null) withTimeout(timeoutMillis) { connected() } else connected()
+            connectedSocket.setNoDelay(noDelay)
+            JsNodeTcpSocket(connectedSocket)
+        } catch (e: Throwable) {
+            if (socket != null) socket.destroy()
+            throw e
+        }
+    }
+
+    override suspend fun tcpListen(
+        host: String?,
+        port: Int,
+        backlog: Int,
+        reuseAddress: Boolean,
+    ): LyngTcpServer {
+        val accepted = Channel<LyngTcpSocket>(Channel.UNLIMITED)
+        val server = netModule.createServer({ socket: dynamic ->
+            accepted.trySend(JsNodeTcpSocket(socket))
+        })
+        server.on("error", { _: dynamic -> })
+        val listenHost = host ?: "0.0.0.0"
+        val options = json(
+            "host" to listenHost,
+            "port" to port,
+            "backlog" to backlog,
+            "exclusive" to !reuseAddress,
+        )
+        suspendCancellableCoroutine<Unit> { cont ->
+            server.once("error", { error: dynamic ->
+                if (cont.isActive) {
+                    cont.resumeWithException(IllegalStateException(error.message?.unsafeCast<String>() ?: "TCP listen failed"))
+                }
+            })
+            server.listen(options) {
+                if (cont.isActive) cont.resume(Unit)
+            }
+        }
+        return JsNodeTcpServer(server, accepted)
+    }
+
+    override suspend fun udpBind(host: String?, port: Int, reuseAddress: Boolean): LyngUdpSocket {
+        val socketType = if ((host ?: "").contains(':')) "udp6" else "udp4"
+        val socket = dgramModule.createSocket(json("type" to socketType, "reuseAddr" to reuseAddress))
+        val incoming = Channel<LyngDatagram>(Channel.UNLIMITED)
+        socket.on("message", { msg: dynamic, rinfo: dynamic ->
+            incoming.trySend(
+                LyngDatagram(
+                    data = dynamicToByteArray(msg),
+                    address = rinfoToAddress(rinfo),
+                )
+            )
+        })
+        socket.on("error", { _: dynamic -> })
+        suspendCancellableCoroutine<Unit> { cont ->
+            socket.once("error", { error: dynamic ->
+                if (cont.isActive) {
+                    cont.resumeWithException(IllegalStateException(error.message?.unsafeCast<String>() ?: "UDP bind failed"))
+                }
+            })
+            socket.bind(port, host ?: "0.0.0.0") {
+                if (cont.isActive) cont.resume(Unit)
+            }
+        }
+        return JsNodeUdpSocket(socket, incoming)
+    }
+}
+
+private class JsNodeTcpSocket(
+    private val socket: dynamic,
+) : LyngTcpSocket {
+    private val incoming = Channel<ByteArray?>(Channel.UNLIMITED)
+    private val buffered = ArrayDeque<Byte>()
+    private var closed = false
+    private var failure: Throwable? = null
+
+    init {
+        socket.on("data", { chunk: dynamic ->
+            incoming.trySend(dynamicToByteArray(chunk))
+        })
+        socket.on("end", {
+            closed = true
+            incoming.trySend(null)
+        })
+        socket.on("close", {
+            closed = true
+            incoming.trySend(null)
+        })
+        socket.on("error", { error: dynamic ->
+            failure = IllegalStateException(error.message?.unsafeCast<String>() ?: "TCP socket failed")
+            closed = true
+            incoming.trySend(null)
+        })
+    }
+
+    override fun isOpen(): Boolean = !closed && socket.destroyed != true
+
+    override fun localAddress(): LyngSocketAddress = socketAddress(
+        host = socket.localAddress?.unsafeCast<String>() ?: "0.0.0.0",
+        port = socket.localPort?.unsafeCast<Int>() ?: 0,
+        family = socket.localFamily,
+        resolved = true,
+    )
+
+    override fun remoteAddress(): LyngSocketAddress = socketAddress(
+        host = socket.remoteAddress?.unsafeCast<String>() ?: "0.0.0.0",
+        port = socket.remotePort?.unsafeCast<Int>() ?: 0,
+        family = socket.remoteFamily,
+        resolved = true,
+    )
+
+    override suspend fun read(maxBytes: Int): ByteArray? {
+        if (!ensureBuffered()) return null
+        val count = minOf(maxBytes, buffered.size)
+        return ByteArray(count) { buffered.removeFirst() }
+    }
+
+    override suspend fun readLine(): String? {
+        while (true) {
+            val newlineIndex = buffered.indexOfFirst { it == '\n'.code.toByte() }
+            if (newlineIndex >= 0) {
+                val raw = takeBuffered(newlineIndex + 1)
+                val trimmed = if (raw.lastOrNull() == '\n'.code.toByte()) raw.dropLast(1) else raw
+                val withoutCr = if (trimmed.lastOrNull() == '\r'.code.toByte()) trimmed.dropLast(1) else trimmed
+                return withoutCr.toByteArray().decodeToString()
+            }
+            if (!fillBuffer()) break
+        }
+        if (buffered.isEmpty()) {
+            failure?.let { throw it }
+            return null
+        }
+        return takeBuffered(buffered.size).toByteArray().decodeToString()
+    }
+
+    override suspend fun write(data: ByteArray) {
+        ensureOpen()
+        suspendCancellableCoroutine<Unit> { cont ->
+            socket.write(byteArrayToUint8Array(data), { error: dynamic ->
+                if (!cont.isActive) return@write
+                if (error != null) {
+                    cont.resumeWithException(IllegalStateException(error.message?.unsafeCast<String>() ?: "TCP write failed"))
+                } else {
+                    cont.resume(Unit)
+                }
+            })
+        }
+    }
+
+    override suspend fun writeUtf8(text: String) {
+        ensureOpen()
+        suspendCancellableCoroutine<Unit> { cont ->
+            socket.write(text, "utf8", { error: dynamic ->
+                if (!cont.isActive) return@write
+                if (error != null) {
+                    cont.resumeWithException(IllegalStateException(error.message?.unsafeCast<String>() ?: "TCP write failed"))
+                } else {
+                    cont.resume(Unit)
+                }
+            })
+        }
+    }
+
+    override suspend fun flush() {
+        ensureOpen()
+        if (socket.writableNeedDrain == true) {
+            withTimeoutOrNull(5_000) {
+                awaitNodeEvent(socket, "drain")
+            }
+        }
+    }
+
+    override fun close() {
+        if (closed) return
+        closed = true
+        if (socket.destroyed == true) {
+            incoming.trySend(null)
+            return
+        }
+        if (socket.writable == true) socket.end() else socket.destroy()
+    }
+
+    private suspend fun ensureBuffered(): Boolean {
+        if (buffered.isNotEmpty()) return true
+        return fillBuffer()
+    }
+
+    private suspend fun fillBuffer(): Boolean {
+        while (buffered.isEmpty()) {
+            val chunk = incoming.receive()
+            if (chunk == null) {
+                failure?.let { if (buffered.isEmpty()) throw it }
+                return buffered.isNotEmpty()
+            }
+            chunk.forEach { buffered.addLast(it) }
+        }
+        return true
+    }
+
+    private fun takeBuffered(count: Int): List<Byte> = List(count) { buffered.removeFirst() }
+
+    private fun ensureOpen() {
+        if (!isOpen()) throw IllegalStateException("tcp socket is closed")
+    }
+}
+
+private class JsNodeTcpServer(
+    private val server: dynamic,
+    private val accepted: Channel<LyngTcpSocket>,
+) : LyngTcpServer {
+    private var closed = false
+
+    override fun isOpen(): Boolean = !closed && server.listening == true
+
+    override fun localAddress(): LyngSocketAddress {
+        val info = server.address()
+        return socketAddress(
+            host = info.address?.unsafeCast<String>() ?: "0.0.0.0",
+            port = info.port?.unsafeCast<Int>() ?: 0,
+            family = info.family,
+            resolved = true,
+        )
+    }
+
+    override suspend fun accept(): LyngTcpSocket = accepted.receive()
+
+    override fun close() {
+        if (closed) return
+        closed = true
+        server.close()
+        accepted.close()
+    }
+}
+
+private class JsNodeUdpSocket(
+    private val socket: dynamic,
+    private val incoming: Channel<LyngDatagram>,
+) : LyngUdpSocket {
+    private var closed = false
+
+    override fun isOpen(): Boolean = !closed
+
+    override fun localAddress(): LyngSocketAddress = rinfoToAddress(socket.address())
+
+    override suspend fun receive(maxBytes: Int): LyngDatagram? {
+        val datagram = incoming.receiveCatching().getOrNull() ?: return null
+        return if (datagram.data.size <= maxBytes) datagram else datagram.copy(data = datagram.data.copyOf(maxBytes))
+    }
+
+    override suspend fun send(data: ByteArray, host: String, port: Int) {
+        if (closed) throw IllegalStateException("udp socket is closed")
+        suspendCancellableCoroutine<Unit> { cont ->
+            socket.send(byteArrayToUint8Array(data), port, host, { error: dynamic ->
+                if (!cont.isActive) return@send
+                if (error != null) {
+                    cont.resumeWithException(IllegalStateException(error.message?.unsafeCast<String>() ?: "UDP send failed"))
+                } else {
+                    cont.resume(Unit)
+                }
+            })
+        }
+    }
+
+    override fun close() {
+        if (closed) return
+        closed = true
+        socket.close()
+        incoming.close()
+    }
+}
+
+private suspend fun awaitNodeEvent(target: dynamic, name: String) {
+    suspendCancellableCoroutine<Unit> { cont ->
+        target.once("error", { error: dynamic ->
+            if (cont.isActive) {
+                cont.resumeWithException(IllegalStateException(error.message?.unsafeCast<String>() ?: "Node operation failed"))
+            }
+        })
+        target.once(name) {
+            if (cont.isActive) cont.resume(Unit)
+        }
+    }
+}
+
+private fun socketAddress(host: String, port: Int, family: dynamic, resolved: Boolean): LyngSocketAddress =
+    LyngSocketAddress(
+        host = host,
+        port = port,
+        ipVersion = when (family?.toString()) {
+            "IPv6", "6" -> LyngIpVersion.IPV6
+            else -> if (host.contains(':')) LyngIpVersion.IPV6 else LyngIpVersion.IPV4
+        },
+        resolved = resolved,
+    )
+
+private fun rinfoToAddress(rinfo: dynamic): LyngSocketAddress = socketAddress(
+    host = rinfo.address?.unsafeCast<String>() ?: "0.0.0.0",
+    port = rinfo.port?.unsafeCast<Int>() ?: 0,
+    family = rinfo.family,
+    resolved = true,
+)
+
+private fun isNodeRuntime(): Boolean = js(
+    """
+    typeof process !== "undefined" &&
+    process != null &&
+    process.versions != null &&
+    process.versions.node != null
+    """
+).unsafeCast<Boolean>()
+
+private fun requireNodeModule(name: String): dynamic {
+    val requireFn = js("typeof require !== 'undefined' ? require : undefined")
+    if (requireFn == js("undefined")) return null
+    return try {
+        requireFn(name)
+    } catch (_: Throwable) {
+        null
+    }
+}
+
+private fun dynamicToByteArray(value: dynamic): ByteArray {
+    val source = js("new Uint8Array(value)").unsafeCast<Uint8Array>()
+    val size = source.length
+    return ByteArray(size) { index -> source.asDynamic()[index].unsafeCast<Byte>() }
+}
+
+private fun byteArrayToUint8Array(value: ByteArray): Uint8Array {
+    val out = Uint8Array(value.size)
+    value.forEachIndexed { index, byte -> out.asDynamic()[index] = byte.toInt() and 0xff }
+    return out
+}

lyngio/src/jsMain/kotlin/net/sergeych/lyngio/ws/PlatformJs.kt

@@ -0,0 +1,5 @@
+package net.sergeych.lyngio.ws
+
+import io.ktor.client.engine.js.Js
+
+actual fun getSystemWsEngine(): LyngWsEngine = createKtorWsEngine(Js)

lyngio/src/jsTest/kotlin/net/sergeych/lyng/io/net/LyngNetModuleJsNodeTest.kt

@@ -0,0 +1,117 @@
+package net.sergeych.lyng.io.net
+
+import kotlinx.coroutines.DelicateCoroutinesApi
+import kotlinx.coroutines.GlobalScope
+import kotlinx.coroutines.async
+import kotlinx.coroutines.promise
+import net.sergeych.lyng.Compiler
+import net.sergeych.lyng.ExecutionError
+import net.sergeych.lyng.Script
+import net.sergeych.lyngio.fs.security.AccessContext
+import net.sergeych.lyngio.fs.security.AccessDecision
+import net.sergeych.lyngio.fs.security.Decision
+import net.sergeych.lyngio.net.getSystemNetEngine
+import net.sergeych.lyngio.net.security.NetAccessOp
+import net.sergeych.lyngio.net.security.NetAccessPolicy
+import net.sergeych.lyngio.net.security.PermitAllNetAccessPolicy
+import kotlin.test.Test
+import kotlin.test.assertFailsWith
+import kotlin.test.assertTrue
+
+@OptIn(DelicateCoroutinesApi::class)
+class LyngNetModuleJsNodeTest {
+    @Test
+    fun testResolveAndCapabilities() = GlobalScope.promise {
+        val scope = Script.newScope()
+        createNetModule(PermitAllNetAccessPolicy, scope)
+
+        val code = """
+            import lyng.io.net
+
+            val a: SocketAddress = Net.resolve("127.0.0.1", 4040)[0]
+            [Net.isSupported(), Net.isTcpAvailable(), Net.isTcpServerAvailable(), Net.isUdpAvailable(), a.toString(), a.resolved, a.ipVersion == IpVersion.IPV4]
+        """.trimIndent()
+
+        val result = Compiler.compile(code).execute(scope).inspect(scope)
+        assertTrue(result.contains("true,true,true,true"), result)
+        assertTrue(result.contains("127.0.0.1:4040"), result)
+    }
+
+    @Test
+    fun testTcpConnectConvenience() = GlobalScope.promise {
+        val engine = getSystemNetEngine()
+        val server = engine.tcpListen(host = "127.0.0.1", port = 0, backlog = 8, reuseAddress = true)
+        val serverPort = server.localAddress().port
+        val worker = async {
+            val client = server.accept()
+            val line = client.read(4)?.decodeToString()
+            client.writeUtf8("reply:$line")
+            client.flush()
+            client.close()
+        }
+
+        val scope = Script.newScope()
+        createNetModule(PermitAllNetAccessPolicy, scope)
+        val code = """
+            import lyng.buffer
+            import lyng.io.net
+
+            val socket = Net.tcpConnect("127.0.0.1", $serverPort)
+            socket.writeUtf8("ping")
+            socket.flush()
+            val reply = (socket.read(16) as Buffer).decodeUtf8()
+            val localPort = socket.localAddress().port
+            val remotePort = socket.remoteAddress().port
+            socket.close()
+            [reply, localPort > 0, remotePort == $serverPort]
+        """.trimIndent()
+
+        val result = Compiler.compile(code).execute(scope).inspect(scope)
+        worker.await()
+        server.close()
+        assertTrue(result.contains("reply:ping"), result)
+        assertTrue(result.contains("true,true"), result)
+    }
+
+    @Test
+    fun testUdpLoopback() = GlobalScope.promise {
+        val scope = Script.newScope()
+        createNetModule(PermitAllNetAccessPolicy, scope)
+
+        val code = """
+            import lyng.buffer
+            import lyng.io.net
+
+            val server = Net.udpBind(0, "127.0.0.1")
+            val client = Net.udpBind(0, "127.0.0.1")
+            client.send(Buffer("ping"), "127.0.0.1", server.localAddress().port)
+            val d = server.receive()
+            client.close()
+            server.close()
+            [d.data.decodeUtf8(), d.address.port > 0]
+        """.trimIndent()
+
+        val result = Compiler.compile(code).execute(scope).inspect(scope)
+        assertTrue(result.contains("[ping,true]"), result)
+    }
+
+    @Test
+    fun testPolicyDenialSurfacesAsLyngError() = GlobalScope.promise {
+        val scope = Script.newScope()
+        val denyAll = object : NetAccessPolicy {
+            override suspend fun check(op: NetAccessOp, ctx: AccessContext): AccessDecision =
+                AccessDecision(Decision.Deny, "blocked by test policy")
+        }
+        createNetModule(denyAll, scope)
+
+        val code = """
+            import lyng.io.net
+            Net.tcpConnect("127.0.0.1", 1)
+        """.trimIndent()
+
+        val error = assertFailsWith<ExecutionError> {
+            Compiler.compile(code).execute(scope)
+        }
+        assertTrue(error.errorMessage.isNotBlank())
+    }
+}

lyngio/src/jsTest/kotlin/net/sergeych/lyngio/NetJsNodeTest.kt

@@ -0,0 +1,70 @@
+package net.sergeych.lyngio
+
+import kotlinx.coroutines.DelicateCoroutinesApi
+import kotlinx.coroutines.GlobalScope
+import kotlinx.coroutines.async
+import kotlinx.coroutines.promise
+import net.sergeych.lyngio.net.LyngIpVersion
+import net.sergeych.lyngio.net.getSystemNetEngine
+import kotlin.test.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertNotNull
+import kotlin.test.assertTrue
+
+@OptIn(DelicateCoroutinesApi::class)
+class NetJsNodeTest {
+    @Test
+    fun testNodeNetCapabilitiesAndResolve() = GlobalScope.promise {
+        val engine = getSystemNetEngine()
+        assertTrue(engine.isSupported)
+        assertTrue(engine.isTcpAvailable)
+        assertTrue(engine.isTcpServerAvailable)
+        assertTrue(engine.isUdpAvailable)
+
+        val resolved = engine.resolve("127.0.0.1", 4040)
+        assertTrue(resolved.isNotEmpty())
+        assertEquals(4040, resolved.first().port)
+        assertEquals(LyngIpVersion.IPV4, resolved.first().ipVersion)
+    }
+
+    @Test
+    fun testNodeTcpLoopback() = GlobalScope.promise {
+        val engine = getSystemNetEngine()
+        val server = engine.tcpListen(host = "127.0.0.1", port = 0, backlog = 8, reuseAddress = true)
+        val accepted = async {
+            val socket = server.accept()
+            val line = socket.readLine()
+            socket.writeUtf8("echo:$line\n")
+            socket.flush()
+            socket.close()
+            line
+        }
+
+        val client = engine.tcpConnect("127.0.0.1", server.localAddress().port, timeoutMillis = null, noDelay = true)
+        client.writeUtf8("ping\n")
+        client.flush()
+        val reply = client.readLine()
+        client.close()
+        server.close()
+
+        assertEquals("ping", accepted.await())
+        assertEquals("echo:ping", reply)
+    }
+
+    @Test
+    fun testNodeUdpLoopback() = GlobalScope.promise {
+        val engine = getSystemNetEngine()
+        val server = engine.udpBind(host = "127.0.0.1", port = 0, reuseAddress = true)
+        val client = engine.udpBind(host = "127.0.0.1", port = 0, reuseAddress = true)
+
+        client.send("ping".encodeToByteArray(), "127.0.0.1", server.localAddress().port)
+        val received = server.receive(1024)
+
+        client.close()
+        server.close()
+
+        assertNotNull(received)
+        assertEquals("ping", received.data.decodeToString())
+        assertTrue(received.address.port > 0)
+    }
+}

lyngio/src/jsTest/kotlin/net/sergeych/lyngio/PlatformCapabilityJsTest.kt

@@ -0,0 +1,14 @@
+package net.sergeych.lyngio
+
+import net.sergeych.lyngio.http.getSystemHttpEngine
+import net.sergeych.lyngio.ws.getSystemWsEngine
+import kotlin.test.Test
+import kotlin.test.assertTrue
+
+class PlatformCapabilityJsTest {
+    @Test
+    fun testJsHttpAndWsCapabilitiesReportSupported() {
+        assertTrue(getSystemHttpEngine().isSupported, "JS HTTP engine should be available")
+        assertTrue(getSystemWsEngine().isSupported, "JS websocket engine should be available")
+    }
+}

lyngio/src/jvmMain/kotlin/net/sergeych/lyngio/http/PlatformJvm.kt

@@ -0,0 +1,5 @@
+package net.sergeych.lyngio.http
+
+import io.ktor.client.engine.cio.CIO
+
+actual fun getSystemHttpEngine(): LyngHttpEngine = createKtorHttpEngine(CIO)

lyngio/src/jvmMain/kotlin/net/sergeych/lyngio/net/PlatformJvm.kt

@@ -0,0 +1,223 @@
+/*
+ * Copyright 2026 Sergey S. Chernov real.sergeych@gmail.com
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package net.sergeych.lyngio.net
+
+import io.ktor.network.selector.ActorSelectorManager
+import io.ktor.network.selector.SelectorManager
+import io.ktor.network.sockets.BoundDatagramSocket
+import io.ktor.network.sockets.InetSocketAddress
+import io.ktor.network.sockets.ServerSocket
+import io.ktor.network.sockets.Socket
+import io.ktor.network.sockets.aSocket
+import io.ktor.network.sockets.isClosed
+import io.ktor.network.sockets.openReadChannel
+import io.ktor.network.sockets.openWriteChannel
+import io.ktor.network.sockets.toJavaAddress
+import io.ktor.utils.io.ByteReadChannel
+import io.ktor.utils.io.ByteWriteChannel
+import io.ktor.utils.io.readAvailable
+import io.ktor.utils.io.readUTF8Line
+import io.ktor.utils.io.writeFully
+import io.ktor.utils.io.writeStringUtf8
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.withContext
+import kotlinx.coroutines.withTimeout
+import kotlinx.io.Buffer
+import kotlinx.io.readByteArray
+import java.net.Inet4Address
+import java.net.Inet6Address
+import java.net.InetAddress
+
+actual fun getSystemNetEngine(): LyngNetEngine = JvmKtorNetEngine
+
+private object JvmKtorNetEngine : LyngNetEngine {
+    private val selectorManager: SelectorManager by lazy { ActorSelectorManager(Dispatchers.IO) }
+
+    override val isSupported: Boolean = true
+    override val isTcpAvailable: Boolean = true
+    override val isTcpServerAvailable: Boolean = true
+    override val isUdpAvailable: Boolean = true
+
+    override suspend fun resolve(host: String, port: Int): List<LyngSocketAddress> = withContext(Dispatchers.IO) {
+        InetAddress.getAllByName(host).map { address ->
+            address.toLyngSocketAddress(port = port, resolved = true)
+        }
+    }
+
+    override suspend fun tcpConnect(
+        host: String,
+        port: Int,
+        timeoutMillis: Long?,
+        noDelay: Boolean,
+    ): LyngTcpSocket {
+        val connectBlock: suspend () -> Socket = {
+            aSocket(selectorManager).tcp().connect(host, port) {
+                this.noDelay = noDelay
+            }
+        }
+        val socket = if (timeoutMillis != null) withTimeout(timeoutMillis) { connectBlock() } else connectBlock()
+        return JvmLyngTcpSocket(socket)
+    }
+
+    override suspend fun tcpListen(
+        host: String?,
+        port: Int,
+        backlog: Int,
+        reuseAddress: Boolean,
+    ): LyngTcpServer {
+        val bindHost = host ?: "0.0.0.0"
+        val server = aSocket(selectorManager).tcp().bind(bindHost, port) {
+            backlogSize = backlog
+            this.reuseAddress = reuseAddress
+        }
+        return JvmLyngTcpServer(server)
+    }
+
+    override suspend fun udpBind(host: String?, port: Int, reuseAddress: Boolean): LyngUdpSocket {
+        val bindHost = host ?: "0.0.0.0"
+        val socket = aSocket(selectorManager).udp().bind(bindHost, port) {
+            this.reuseAddress = reuseAddress
+        }
+        return JvmLyngUdpSocket(socket)
+    }
+}
+
+private class JvmLyngTcpSocket(
+    private val socket: Socket,
+) : LyngTcpSocket {
+    private val input: ByteReadChannel by lazy { socket.openReadChannel() }
+    private val output: ByteWriteChannel by lazy { socket.openWriteChannel(autoFlush = true) }
+
+    override fun isOpen(): Boolean = !socket.isClosed
+
+    override fun localAddress(): LyngSocketAddress = socket.localAddress.toLyngSocketAddress(resolved = true)
+
+    override fun remoteAddress(): LyngSocketAddress = socket.remoteAddress.toLyngSocketAddress(resolved = true)
+
+    override suspend fun read(maxBytes: Int): ByteArray? {
+        if (!input.awaitContent(1)) return null
+        val buffer = ByteArray(maxBytes)
+        val count = input.readAvailable(buffer, 0, maxBytes)
+        return when {
+            count <= 0 -> null
+            count == maxBytes -> buffer
+            else -> buffer.copyOf(count)
+        }
+    }
+
+    override suspend fun readLine(): String? = input.readUTF8Line()
+
+    override suspend fun write(data: ByteArray) {
+        output.writeFully(data, 0, data.size)
+    }
+
+    override suspend fun writeUtf8(text: String) {
+        output.writeStringUtf8(text)
+    }
+
+    override suspend fun flush() {
+        output.flush()
+    }
+
+    override fun close() {
+        socket.close()
+    }
+}
+
+private class JvmLyngTcpServer(
+    private val server: ServerSocket,
+) : LyngTcpServer {
+    override fun isOpen(): Boolean = !server.isClosed
+
+    override fun localAddress(): LyngSocketAddress = server.localAddress.toLyngSocketAddress(resolved = true)
+
+    override suspend fun accept(): LyngTcpSocket = JvmLyngTcpSocket(server.accept())
+
+    override fun close() {
+        server.close()
+    }
+}
+
+private class JvmLyngUdpSocket(
+    private val socket: BoundDatagramSocket,
+) : LyngUdpSocket {
+    override fun isOpen(): Boolean = !socket.isClosed
+
+    override fun localAddress(): LyngSocketAddress = socket.localAddress.toLyngSocketAddress(resolved = true)
+
+    override suspend fun receive(maxBytes: Int): LyngDatagram? {
+        val datagram = try {
+            socket.receive()
+        } catch (e: Throwable) {
+            if (!isOpen()) return null
+            throw e
+        }
+        val bytes = datagram.packet.readByteArray().let {
+            if (it.size <= maxBytes) it else it.copyOf(maxBytes)
+        }
+        return LyngDatagram(bytes, datagram.address.toLyngSocketAddress(resolved = true))
+    }
+
+    override suspend fun send(data: ByteArray, host: String, port: Int) {
+        val packet = Buffer()
+        packet.write(data)
+        socket.send(io.ktor.network.sockets.Datagram(packet, InetSocketAddress(host, port)))
+    }
+
+    override fun close() {
+        socket.close()
+    }
+}
+
+private fun io.ktor.network.sockets.SocketAddress.toLyngSocketAddress(
+    port: Int? = null,
+    resolved: Boolean,
+): LyngSocketAddress {
+    val javaAddress = this.toJavaAddress()
+    val inetSocket = javaAddress as? java.net.InetSocketAddress
+    if (inetSocket != null) {
+        val inetAddress = inetSocket.address
+        val host = inetAddress?.hostAddress ?: inetSocket.hostString
+        val actualPort = port ?: inetSocket.port
+        val version = when (inetAddress) {
+            is Inet6Address -> LyngIpVersion.IPV6
+            is Inet4Address -> LyngIpVersion.IPV4
+            else -> if (host.contains(':')) LyngIpVersion.IPV6 else LyngIpVersion.IPV4
+        }
+        return LyngSocketAddress(host = host, port = actualPort, ipVersion = version, resolved = resolved)
+    }
+
+    val rendered = toString()
+    return LyngSocketAddress(
+        host = rendered,
+        port = port ?: 0,
+        ipVersion = if (rendered.contains(':')) LyngIpVersion.IPV6 else LyngIpVersion.IPV4,
+        resolved = resolved,
+    )
+}
+
+private fun InetAddress.toLyngSocketAddress(port: Int, resolved: Boolean): LyngSocketAddress =
+    LyngSocketAddress(
+        host = hostAddress,
+        port = port,
+        ipVersion = when (this) {
+            is Inet6Address -> LyngIpVersion.IPV6
+            else -> LyngIpVersion.IPV4
+        },
+        resolved = resolved,
+    )

lyngio/src/jvmMain/kotlin/net/sergeych/lyngio/ws/PlatformJvm.kt

@@ -0,0 +1,22 @@
+/*
+ * Copyright 2026 Sergey S. Chernov real.sergeych@gmail.com
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package net.sergeych.lyngio.ws
+
+import io.ktor.client.engine.cio.CIO
+
+actual fun getSystemWsEngine(): LyngWsEngine = createKtorWsEngine(CIO)

lyngio/src/jvmTest/kotlin/LyngioBookTest.kt

@@ -0,0 +1,256 @@
+/*
+ * Copyright 2026 Sergey S. Chernov real.sergeych@gmail.com
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+import com.sun.net.httpserver.HttpExchange
+import com.sun.net.httpserver.HttpServer
+import com.sun.net.httpserver.HttpsConfigurator
+import com.sun.net.httpserver.HttpsServer
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.flow
+import kotlinx.coroutines.flow.flowOn
+import kotlinx.coroutines.runBlocking
+import net.sergeych.lyng.Scope
+import net.sergeych.lyng.Script
+import net.sergeych.lyng.io.http.createHttpModule
+import net.sergeych.lyng.io.net.createNetModule
+import net.sergeych.lyng.io.testtls.TlsTestMaterial
+import net.sergeych.lyng.io.ws.TestWebSocketServer
+import net.sergeych.lyng.io.ws.createWsModule
+import net.sergeych.lyng.leftMargin
+import net.sergeych.lyng.obj.ObjInt
+import net.sergeych.lyng.obj.ObjString
+import net.sergeych.lyng.obj.ObjVoid
+import net.sergeych.lyngio.http.security.PermitAllHttpAccessPolicy
+import net.sergeych.lyngio.net.security.PermitAllNetAccessPolicy
+import net.sergeych.lyngio.ws.security.PermitAllWsAccessPolicy
+import java.net.InetSocketAddress
+import java.net.ServerSocket
+import java.nio.file.Files.readAllLines
+import java.nio.file.Paths
+import kotlin.concurrent.thread
+import kotlin.io.path.absolutePathString
+import kotlin.test.Test
+import kotlin.test.assertEquals
+
+data class IoDocTest(
+    val fileName: String,
+    val line: Int,
+    val code: String,
+    val expectedOutput: String,
+    val expectedResult: String,
+) {
+    val fileNamePart by lazy { Paths.get(fileName).fileName.toString() }
+
+    override fun toString(): String = "DocTest: ${Paths.get(fileName).absolutePathString()}:${line + 1}"
+}
+
+private fun parseIoDocTests(fileName: String): Flow<IoDocTest> = flow {
+    val book = readAllLines(Paths.get(fileName))
+    var startOffset = 0
+    val block = mutableListOf<String>()
+    var startIndex = 0
+    for ((index, l) in book.withIndex()) {
+        val off = leftMargin(l)
+        when {
+            off < startOffset && startOffset != 0 -> {
+                if (l.isBlank()) continue
+                if (block.size > 1) {
+                    for ((i, s) in block.withIndex()) {
+                        var x = s
+                        val initial = leftMargin(x)
+                        do {
+                            x = x.drop(1)
+                        } while (initial - leftMargin(x) != startOffset)
+                        block[i] = x
+                    }
+                    val outStart = block.indexOfFirst { it.startsWith(">>>") }
+                    if (outStart >= 0) {
+                        val result = mutableListOf<String>()
+                        while (block.lastOrNull()?.isEmpty() == true) block.removeLast()
+                        var valid = true
+                        while (block.size > outStart) {
+                            val line = block.removeAt(outStart)
+                            if (!line.startsWith(">>> ")) {
+                                valid = false
+                                break
+                            }
+                            result.add(line.drop(4))
+                        }
+                        if (valid) {
+                            emit(
+                                IoDocTest(
+                                    fileName = fileName,
+                                    line = startIndex,
+                                    code = block.joinToString("\n"),
+                                    expectedOutput = if (result.size > 1) result.dropLast(1).joinToString("") { "$it\n" } else "",
+                                    expectedResult = result.last(),
+                                )
+                            )
+                        }
+                    }
+                }
+                block.clear()
+                startOffset = 0
+            }
+
+            off != 0 && startOffset == 0 -> {
+                block.clear()
+                startIndex = index
+                block.add(l)
+                startOffset = off
+            }
+
+            off != 0 -> block.add(l)
+        }
+    }
+}.flowOn(Dispatchers.IO)
+
+private suspend fun IoDocTest.run(scope: Scope) {
+    val output = StringBuilder()
+    scope.addFn("println") {
+        for ((i, a) in args.withIndex()) {
+            if (i > 0) output.append(' ')
+            output.append(toStringOf(a).value)
+        }
+        output.append('\n')
+        ObjVoid
+    }
+    val result = scope.eval(code).inspect(scope).replace(Regex("@\\d+"), "@...")
+    assertEquals(expectedOutput, output.toString(), "script output mismatch at $this")
+    assertEquals(expectedResult, result, "script result mismatch at $this")
+}
+
+private suspend fun runIoDocTests(
+    fileName: String,
+    installModules: suspend (Scope) -> Unit,
+    installConsts: suspend (Scope) -> Unit = {},
+) {
+    parseIoDocTests(fileName).collect { test ->
+        val scope = Script.newScope()
+        installModules(scope)
+        installConsts(scope)
+        test.run(scope)
+    }
+}
+
+class LyngioBookTest {
+
+    @Test
+    fun testHttpDocs() = runBlocking {
+        val server = newHttpServer(secure = false)
+        val secureServer = newHttpServer(secure = true)
+        try {
+            runIoDocTests(
+                fileName = "../docs/lyng.io.http.md",
+                installModules = { scope -> createHttpModule(PermitAllHttpAccessPolicy, scope) },
+                installConsts = { scope ->
+                    scope.addConst("HTTP_TEST_URL", ObjString("http://127.0.0.1:${server.address.port}"))
+                    scope.addConst("HTTPS_TEST_URL", ObjString("https://127.0.0.1:${secureServer.address.port}"))
+                },
+            )
+        } finally {
+            server.stop(0)
+            secureServer.stop(0)
+        }
+    }
+
+    @Test
+    fun testNetDocs() = runBlocking {
+        ServerSocket(0, 50).use { server ->
+            val worker = thread(start = true) {
+                server.accept().use { client ->
+                    val line = client.getInputStream().readNBytes(4).decodeToString()
+                    client.getOutputStream().write(("reply:" + line).toByteArray())
+                    client.getOutputStream().flush()
+                }
+            }
+            try {
+                runIoDocTests(
+                    fileName = "../docs/lyng.io.net.md",
+                    installModules = { scope -> createNetModule(PermitAllNetAccessPolicy, scope) },
+                    installConsts = { scope -> scope.addConst("NET_TEST_TCP_PORT", ObjInt(server.localPort.toLong())) },
+                )
+            } finally {
+                worker.join(2000)
+            }
+        }
+    }
+
+    @Test
+    fun testWsDocs() = runBlocking {
+        TestWebSocketServer { connection ->
+            val text = connection.receiveText()
+            connection.sendText("echo:$text")
+            connection.close()
+        }.use { textServer ->
+            TestWebSocketServer { connection ->
+                val data = connection.receiveBinary()
+                connection.sendBinary(byteArrayOf(1, 2, 3) + data)
+                connection.close()
+            }.use { binaryServer ->
+                TestWebSocketServer(secure = true) { connection ->
+                    val text = connection.receiveText()
+                    connection.sendText("secure:$text")
+                    connection.close()
+                }.use { secureServer ->
+                    runIoDocTests(
+                        fileName = "../docs/lyng.io.ws.md",
+                        installModules = { scope -> createWsModule(PermitAllWsAccessPolicy, scope) },
+                        installConsts = { scope ->
+                            scope.addConst("WS_TEST_URL", ObjString(textServer.url))
+                            scope.addConst("WS_TEST_BINARY_URL", ObjString(binaryServer.url))
+                            scope.addConst("WSS_TEST_URL", ObjString(secureServer.url))
+                        },
+                    )
+                }
+            }
+        }
+    }
+
+    private fun writeResponse(exchange: HttpExchange, status: Int, body: String) {
+        val bytes = body.toByteArray()
+        exchange.sendResponseHeaders(status, bytes.size.toLong())
+        exchange.responseBody.use { it.write(bytes) }
+    }
+
+    private fun newHttpServer(secure: Boolean): HttpServer {
+        if (secure) TlsTestMaterial.installJvmClientTrust()
+        val server = if (secure) {
+            HttpsServer.create(InetSocketAddress("127.0.0.1", 0), 0).apply {
+                httpsConfigurator = HttpsConfigurator(TlsTestMaterial.sslContext)
+            }
+        } else {
+            HttpServer.create(InetSocketAddress("127.0.0.1", 0), 0)
+        }
+        server.createContext("/hello") { exchange ->
+            exchange.responseHeaders.add("Content-Type", "text/plain; charset=utf-8")
+            writeResponse(exchange, 200, "hello from test")
+        }
+        server.createContext("/headers") { exchange ->
+            exchange.responseHeaders.add("X-Reply", "one")
+            exchange.responseHeaders.add("X-Reply", "two")
+            writeResponse(exchange, 200, "header demo")
+        }
+        server.createContext("/echo") { exchange ->
+            val body = exchange.requestBody.readBytes().decodeToString()
+            writeResponse(exchange, 200, exchange.requestMethod + ":" + body)
+        }
+        server.start()
+        return server
+    }
+}

lyngio/src/jvmTest/kotlin/net/sergeych/lyng/io/http/LyngHttpModuleTest.kt

@@ -0,0 +1,176 @@
+/*
+ * Copyright 2026 Sergey S. Chernov real.sergeych@gmail.com
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package net.sergeych.lyng.io.http
+
+import com.sun.net.httpserver.HttpExchange
+import com.sun.net.httpserver.HttpServer
+import com.sun.net.httpserver.HttpsConfigurator
+import com.sun.net.httpserver.HttpsServer
+import kotlinx.coroutines.runBlocking
+import net.sergeych.lyng.Compiler
+import net.sergeych.lyng.ExecutionError
+import net.sergeych.lyng.Script
+import net.sergeych.lyng.io.testtls.TlsTestMaterial
+import net.sergeych.lyngio.fs.security.AccessContext
+import net.sergeych.lyngio.fs.security.AccessDecision
+import net.sergeych.lyngio.fs.security.Decision
+import net.sergeych.lyngio.http.security.HttpAccessOp
+import net.sergeych.lyngio.http.security.HttpAccessPolicy
+import net.sergeych.lyngio.http.security.PermitAllHttpAccessPolicy
+import java.net.InetSocketAddress
+import kotlin.test.Test
+import kotlin.test.assertFailsWith
+import kotlin.test.assertTrue
+
+class LyngHttpModuleTest {
+
+    @Test
+    fun testConvenienceGetAndHeaders() = runBlocking {
+        val server = newServer { exchange ->
+            exchange.responseHeaders.add("Content-Type", "text/plain; charset=utf-8")
+            exchange.responseHeaders.add("X-Reply", "one")
+            exchange.responseHeaders.add("X-Reply", "two")
+            writeResponse(exchange, 200, "hello from test")
+        }
+        try {
+            val scope = Script.newScope()
+            createHttpModule(PermitAllHttpAccessPolicy, scope)
+
+            val code = """
+                import lyng.io.http
+
+                val r = Http.get(
+                    "http://127.0.0.1:${server.address.port}/hello",
+                    "Accept" => "text/plain",
+                    "X-Test" => "yes"
+                )
+                [r.status, r.headers["Content-Type"], r.headers.getAll("X-Reply").size, r.text()]
+            """.trimIndent()
+
+            val result = Compiler.compile(code).execute(scope)
+            val rendered = result.inspect(scope)
+            assertTrue(rendered.contains("200"), rendered)
+            assertTrue(rendered.contains("text/plain"), rendered)
+            assertTrue(rendered.contains("2"), rendered)
+            assertTrue(rendered.contains("hello from test"), rendered)
+        } finally {
+            server.stop(0)
+        }
+    }
+
+    @Test
+    fun testMutableRequestPost() = runBlocking {
+        val server = newServer { exchange ->
+            val body = exchange.requestBody.readBytes().decodeToString()
+            exchange.responseHeaders.add("Content-Type", "text/plain")
+            writeResponse(exchange, 200, exchange.requestMethod + ":" + body)
+        }
+        try {
+            val scope = Script.newScope()
+            createHttpModule(PermitAllHttpAccessPolicy, scope)
+
+            val code = """
+                import lyng.io.http
+
+                val q = HttpRequest()
+                q.method = "POST"
+                q.url = "http://127.0.0.1:${server.address.port}/echo"
+                q.headers = Map("Content-Type" => "text/plain")
+                q.bodyText = "ping"
+
+                val r = Http.request(q)
+                r.text()
+            """.trimIndent()
+
+            val result = Compiler.compile(code).execute(scope)
+            assertTrue(result.inspect(scope).contains("POST:ping"))
+        } finally {
+            server.stop(0)
+        }
+    }
+
+    @Test
+    fun testHttpsGet() = runBlocking {
+        TlsTestMaterial.installJvmClientTrust()
+        val server = newServer(secure = true) { exchange ->
+            exchange.responseHeaders.add("Content-Type", "text/plain; charset=utf-8")
+            writeResponse(exchange, 200, "hello over tls")
+        }
+        try {
+            val scope = Script.newScope()
+            createHttpModule(PermitAllHttpAccessPolicy, scope)
+
+            val code = """
+                import lyng.io.http
+
+                val r = Http.get("https://127.0.0.1:${server.address.port}/hello")
+                [r.status, r.text()]
+            """.trimIndent()
+
+            val result = Compiler.compile(code).execute(scope)
+            val rendered = result.inspect(scope)
+            assertTrue(rendered.contains("200"), rendered)
+            assertTrue(rendered.contains("hello over tls"), rendered)
+        } finally {
+            server.stop(0)
+        }
+    }
+
+    @Test
+    fun testPolicyDenialSurfacesAsLyngError() = runBlocking {
+        val scope = Script.newScope()
+        val denyAll = object : HttpAccessPolicy {
+            override suspend fun check(op: HttpAccessOp, ctx: AccessContext): AccessDecision =
+                AccessDecision(Decision.Deny, "blocked by test policy")
+        }
+        createHttpModule(denyAll, scope)
+
+        val code = """
+            import lyng.io.http
+            Http.get("http://127.0.0.1:1/")
+        """.trimIndent()
+
+        val error = assertFailsWith<ExecutionError> {
+            Compiler.compile(code).execute(scope)
+        }
+        assertTrue(error.errorMessage.isNotBlank())
+    }
+
+    private fun newServer(secure: Boolean = false, handler: (HttpExchange) -> Unit): HttpServer {
+        val server = if (secure) {
+            HttpsServer.create(InetSocketAddress("127.0.0.1", 0), 0).apply {
+                httpsConfigurator = HttpsConfigurator(TlsTestMaterial.sslContext)
+            }
+        } else {
+            HttpServer.create(InetSocketAddress("127.0.0.1", 0), 0)
+        }
+        server.createContext("/") { exchange ->
+            handler(exchange)
+        }
+        server.start()
+        return server
+    }
+
+    private fun writeResponse(exchange: HttpExchange, status: Int, body: String) {
+        val bytes = body.toByteArray()
+        exchange.sendResponseHeaders(status, bytes.size.toLong())
+        exchange.responseBody.use { out ->
+            out.write(bytes)
+        }
+    }
+}

lyngio/src/jvmTest/kotlin/net/sergeych/lyng/io/net/LyngNetModuleTest.kt

@@ -0,0 +1,168 @@
+/*
+ * Copyright 2026 Sergey S. Chernov real.sergeych@gmail.com
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package net.sergeych.lyng.io.net
+
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.runBlocking
+import kotlinx.coroutines.withContext
+import net.sergeych.lyng.Compiler
+import net.sergeych.lyng.ExecutionError
+import net.sergeych.lyng.Script
+import net.sergeych.lyngio.fs.security.AccessContext
+import net.sergeych.lyngio.fs.security.AccessDecision
+import net.sergeych.lyngio.fs.security.Decision
+import net.sergeych.lyngio.net.security.NetAccessOp
+import net.sergeych.lyngio.net.security.NetAccessPolicy
+import net.sergeych.lyngio.net.security.PermitAllNetAccessPolicy
+import java.net.DatagramPacket
+import java.net.DatagramSocket
+import java.net.ServerSocket
+import java.net.Socket
+import kotlin.concurrent.thread
+import kotlin.test.Test
+import kotlin.test.assertFailsWith
+import kotlin.test.assertTrue
+
+class LyngNetModuleTest {
+
+    @Test
+    fun testResolveAndCapabilities() = runBlocking {
+        val scope = Script.newScope()
+        createNetModule(PermitAllNetAccessPolicy, scope)
+
+        val code = """
+            import lyng.io.net
+
+            val a: SocketAddress = Net.resolve("127.0.0.1", 4040)[0]
+            [Net.isSupported(), Net.isTcpAvailable(), Net.isTcpServerAvailable(), Net.isUdpAvailable(), a.toString(), a.resolved, a.ipVersion == IpVersion.IPV4]
+        """.trimIndent()
+
+        val result = Compiler.compile(code).execute(scope).inspect(scope)
+        assertTrue(result.contains("true,true,true,true"), result)
+        assertTrue(result.contains("127.0.0.1:4040"), result)
+    }
+
+    @Test
+    fun testTcpConnectConvenience() = runBlocking {
+        ServerSocket(0, 50).use { server ->
+            val worker = thread(start = true) {
+                server.accept().use { client ->
+                    val line = client.getInputStream().readNBytes(4).decodeToString()
+                    client.getOutputStream().write(("reply:" + line).toByteArray())
+                    client.getOutputStream().flush()
+                }
+            }
+
+            val scope = Script.newScope()
+            createNetModule(PermitAllNetAccessPolicy, scope)
+            val code = """
+                import lyng.buffer
+                import lyng.io.net
+
+                val socket = Net.tcpConnect("127.0.0.1", ${server.localPort})
+                socket.writeUtf8("ping")
+                socket.flush()
+                val reply = (socket.read(16) as Buffer).decodeUtf8()
+                val localPort = socket.localAddress().port
+                val remotePort = socket.remoteAddress().port
+                socket.close()
+                [reply, localPort > 0, remotePort == ${server.localPort}]
+            """.trimIndent()
+
+            val result = Compiler.compile(code).execute(scope).inspect(scope)
+            worker.join(2000)
+            assertTrue(result.contains("reply:ping"), result)
+            assertTrue(result.contains("true,true"), result)
+        }
+    }
+
+    @Test
+    fun testTcpListenAndAcceptInLyng() = runBlocking {
+        val scope = Script.newScope()
+        createNetModule(PermitAllNetAccessPolicy, scope)
+
+        val code = """
+            import lyng.buffer
+            import lyng.io.net
+
+            val server = Net.tcpListen(0, "127.0.0.1")
+            val port = server.localAddress().port
+            val accepted = launch {
+                val client = server.accept()
+                val line = (client.read(4) as Buffer).decodeUtf8()
+                client.writeUtf8("echo:" + line)
+                client.flush()
+                client.close()
+                server.close()
+                line
+            }
+
+            val socket = Net.tcpConnect("127.0.0.1", port)
+            socket.writeUtf8("ping")
+            socket.flush()
+            val reply = (socket.read(16) as Buffer).decodeUtf8()
+            socket.close()
+            [accepted.await(), reply]
+        """.trimIndent()
+
+        val result = Compiler.compile(code).execute(scope).inspect(scope)
+        assertTrue(result.contains("[ping,echo:ping]"), result)
+    }
+
+    @Test
+    fun testUdpLoopback() = runBlocking {
+        val scope = Script.newScope()
+        createNetModule(PermitAllNetAccessPolicy, scope)
+
+        val code = """
+            import lyng.buffer
+            import lyng.io.net
+
+            val server = Net.udpBind(0, "127.0.0.1")
+            val client = Net.udpBind(0, "127.0.0.1")
+            client.send(Buffer("ping"), "127.0.0.1", server.localAddress().port)
+            val d = server.receive()
+            client.close()
+            server.close()
+            [d.data.decodeUtf8(), d.address.port > 0]
+        """.trimIndent()
+
+        val result = Compiler.compile(code).execute(scope).inspect(scope)
+        assertTrue(result.contains("[ping,true]"), result)
+    }
+
+    @Test
+    fun testPolicyDenialSurfacesAsLyngError() = runBlocking {
+        val scope = Script.newScope()
+        val denyAll = object : NetAccessPolicy {
+            override suspend fun check(op: NetAccessOp, ctx: AccessContext): AccessDecision =
+                AccessDecision(Decision.Deny, "blocked by test policy")
+        }
+        createNetModule(denyAll, scope)
+
+        val code = """
+            import lyng.io.net
+            Net.tcpConnect("127.0.0.1", 1)
+        """.trimIndent()
+
+        val error = assertFailsWith<ExecutionError> {
+            Compiler.compile(code).execute(scope)
+        }
+        assertTrue(error.errorMessage.isNotBlank())
+    }
+}

lyngio/src/jvmTest/kotlin/net/sergeych/lyng/io/testtls/TlsTestMaterial.kt

@@ -0,0 +1,123 @@
+/*
+ * Copyright 2026 Sergey S. Chernov real.sergeych@gmail.com
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package net.sergeych.lyng.io.testtls
+
+import java.nio.file.Files
+import java.nio.file.Path
+import java.security.KeyStore
+import javax.net.ssl.KeyManagerFactory
+import javax.net.ssl.SSLContext
+import javax.net.ssl.SSLServerSocketFactory
+import javax.net.ssl.TrustManagerFactory
+import kotlin.io.path.absolutePathString
+
+internal object TlsTestMaterial {
+    private const val STORE_PASSWORD = "changeit"
+    private const val KEY_ALIAS = "lyng-io-test"
+
+    private val dir: Path by lazy { Files.createTempDirectory("lyng-io-tls-test-") }
+    private val serverStore: Path by lazy { dir.resolve("server.p12") }
+    private val trustStore: Path by lazy { dir.resolve("trust.p12") }
+    private val certFile: Path by lazy { dir.resolve("server.cer") }
+
+    val serverSocketFactory: SSLServerSocketFactory by lazy {
+        ensureGenerated()
+        val keyStore = KeyStore.getInstance("PKCS12")
+        serverStore.toFile().inputStream().use { keyStore.load(it, STORE_PASSWORD.toCharArray()) }
+        val kmf = KeyManagerFactory.getInstance(KeyManagerFactory.getDefaultAlgorithm())
+        kmf.init(keyStore, STORE_PASSWORD.toCharArray())
+        SSLContext.getInstance("TLS").apply {
+            init(kmf.keyManagers, null, null)
+        }.serverSocketFactory
+    }
+
+    val sslContext: SSLContext by lazy {
+        ensureGenerated()
+        val keyStore = KeyStore.getInstance("PKCS12")
+        serverStore.toFile().inputStream().use { keyStore.load(it, STORE_PASSWORD.toCharArray()) }
+        val kmf = KeyManagerFactory.getInstance(KeyManagerFactory.getDefaultAlgorithm())
+        kmf.init(keyStore, STORE_PASSWORD.toCharArray())
+        val trust = KeyStore.getInstance("PKCS12")
+        trustStore.toFile().inputStream().use { trust.load(it, STORE_PASSWORD.toCharArray()) }
+        val tmf = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm())
+        tmf.init(trust)
+        SSLContext.getInstance("TLS").apply {
+            init(kmf.keyManagers, tmf.trustManagers, null)
+        }
+    }
+
+    fun installJvmClientTrust() {
+        ensureGenerated()
+        System.setProperty("javax.net.ssl.trustStore", trustStore.absolutePathString())
+        System.setProperty("javax.net.ssl.trustStorePassword", STORE_PASSWORD)
+        System.setProperty("javax.net.ssl.trustStoreType", "PKCS12")
+
+        val trust = KeyStore.getInstance("PKCS12")
+        trustStore.toFile().inputStream().use { trust.load(it, STORE_PASSWORD.toCharArray()) }
+        val tmf = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm())
+        tmf.init(trust)
+        SSLContext.setDefault(
+            SSLContext.getInstance("TLS").apply {
+                init(null, tmf.trustManagers, null)
+            }
+        )
+    }
+
+    private fun ensureGenerated() {
+        if (Files.exists(serverStore) && Files.exists(trustStore) && Files.exists(certFile)) return
+        runKeytool(
+            "-genkeypair",
+            "-alias", KEY_ALIAS,
+            "-keyalg", "RSA",
+            "-keysize", "2048",
+            "-validity", "2",
+            "-storetype", "PKCS12",
+            "-keystore", serverStore.absolutePathString(),
+            "-storepass", STORE_PASSWORD,
+            "-keypass", STORE_PASSWORD,
+            "-dname", "CN=127.0.0.1, OU=Lyng, O=Lyng, L=Test, ST=Test, C=US",
+            "-ext", "SAN=ip:127.0.0.1,dns:localhost",
+        )
+        runKeytool(
+            "-exportcert",
+            "-alias", KEY_ALIAS,
+            "-keystore", serverStore.absolutePathString(),
+            "-storepass", STORE_PASSWORD,
+            "-rfc",
+            "-file", certFile.absolutePathString(),
+        )
+        runKeytool(
+            "-importcert",
+            "-noprompt",
+            "-alias", KEY_ALIAS,
+            "-storetype", "PKCS12",
+            "-keystore", trustStore.absolutePathString(),
+            "-storepass", STORE_PASSWORD,
+            "-file", certFile.absolutePathString(),
+        )
+    }
+
+    private fun runKeytool(vararg args: String) {
+        val process = ProcessBuilder(listOf("keytool") + args)
+            .redirectErrorStream(true)
+            .start()
+        val output = process.inputStream.bufferedReader().readText()
+        val code = process.waitFor()
+        require(code == 0) { "keytool failed: $output" }
+    }
+}

lyngio/src/jvmTest/kotlin/net/sergeych/lyng/io/ws/LyngWsModuleTest.kt

@@ -0,0 +1,135 @@
+/*
+ * Copyright 2026 Sergey S. Chernov real.sergeych@gmail.com
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package net.sergeych.lyng.io.ws
+
+import kotlinx.coroutines.runBlocking
+import net.sergeych.lyng.Compiler
+import net.sergeych.lyng.ExecutionError
+import net.sergeych.lyng.Script
+import net.sergeych.lyngio.fs.security.AccessContext
+import net.sergeych.lyngio.fs.security.AccessDecision
+import net.sergeych.lyngio.fs.security.Decision
+import net.sergeych.lyngio.ws.security.PermitAllWsAccessPolicy
+import net.sergeych.lyngio.ws.security.WsAccessOp
+import net.sergeych.lyngio.ws.security.WsAccessPolicy
+import kotlin.test.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertFailsWith
+import kotlin.test.assertTrue
+
+class LyngWsModuleTest {
+
+    @Test
+    fun testTextSessionAndHeaders() = runBlocking {
+        TestWebSocketServer { connection ->
+            assertEquals("yes", connection.requestHeaders["x-test"])
+            val text = connection.receiveText()
+            connection.sendText("echo:$text")
+            connection.close()
+        }.use { server ->
+            val scope = Script.newScope()
+            createWsModule(PermitAllWsAccessPolicy, scope)
+
+            val code = """
+                import lyng.io.ws
+
+                val ws = Ws.connect("${server.url}", "X-Test" => "yes")
+                ws.sendText("ping")
+                val m: WsMessage = ws.receive()
+                ws.close()
+                [ws.url(), m.isText, m.text]
+            """.trimIndent()
+
+            val result = Compiler.compile(code).execute(scope).inspect(scope)
+            assertTrue(result.contains(server.url), result)
+            assertTrue(result.contains("true,echo:ping"), result)
+        }
+    }
+
+    @Test
+    fun testBinarySession() = runBlocking {
+        TestWebSocketServer { connection ->
+            val data = connection.receiveBinary()
+            connection.sendBinary(byteArrayOf(1, 2, 3) + data)
+            connection.close()
+        }.use { server ->
+            val scope = Script.newScope()
+            createWsModule(PermitAllWsAccessPolicy, scope)
+
+            val code = """
+                import lyng.buffer
+                import lyng.io.ws
+
+                val ws = Ws.connect("${server.url}")
+                ws.sendBytes(Buffer(9, 8, 7))
+                val m: WsMessage = ws.receive()
+                ws.close()
+                [m.isText, (m.data as Buffer).hex]
+            """.trimIndent()
+
+            val result = Compiler.compile(code).execute(scope).inspect(scope)
+            assertTrue(result.contains("false,010203090807"), result)
+        }
+    }
+
+    @Test
+    fun testSecureTextSession() = runBlocking {
+        TestWebSocketServer(secure = true) { connection ->
+            val text = connection.receiveText()
+            connection.sendText("secure:$text")
+            connection.close()
+        }.use { server ->
+            val scope = Script.newScope()
+            createWsModule(PermitAllWsAccessPolicy, scope)
+
+            val code = """
+                import lyng.io.ws
+
+                val ws = Ws.connect("${server.url}")
+                ws.sendText("ping")
+                val m: WsMessage = ws.receive()
+                ws.close()
+                [ws.url(), m.text]
+            """.trimIndent()
+
+            val result = Compiler.compile(code).execute(scope).inspect(scope)
+            assertTrue(result.contains(server.url), result)
+            assertTrue(result.contains("secure:ping"), result)
+        }
+    }
+
+    @Test
+    fun testPolicyDenialSurfacesAsLyngError() = runBlocking {
+        val scope = Script.newScope()
+        val denyAll = object : WsAccessPolicy {
+            override suspend fun check(op: WsAccessOp, ctx: AccessContext): AccessDecision =
+                AccessDecision(Decision.Deny, "blocked by test policy")
+        }
+        createWsModule(denyAll, scope)
+
+        val code = """
+            import lyng.io.ws
+            Ws.connect("ws://127.0.0.1:1/ws")
+        """.trimIndent()
+
+        val error = assertFailsWith<ExecutionError> {
+            Compiler.compile(code).execute(scope)
+        }
+        assertTrue(error.errorMessage.isNotBlank())
+    }
+}

lyngio/src/jvmTest/kotlin/net/sergeych/lyng/io/ws/TestWebSocketServer.kt

@@ -0,0 +1,180 @@
+/*
+ * Copyright 2026 Sergey S. Chernov real.sergeych@gmail.com
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package net.sergeych.lyng.io.ws
+
+import net.sergeych.lyng.io.testtls.TlsTestMaterial
+import java.io.BufferedInputStream
+import java.io.BufferedOutputStream
+import java.net.InetAddress
+import java.net.ServerSocket
+import java.net.Socket
+import java.security.MessageDigest
+import java.util.Base64
+import kotlin.concurrent.thread
+
+internal class TestWebSocketServer(
+    secure: Boolean = false,
+    private val handler: (TestWebSocketConnection) -> Unit,
+) : AutoCloseable {
+    private val server: ServerSocket = if (secure) {
+        TlsTestMaterial.installJvmClientTrust()
+        TlsTestMaterial.serverSocketFactory.createServerSocket(0, 50, InetAddress.getByName("127.0.0.1")) as ServerSocket
+    } else {
+        ServerSocket(0, 50, InetAddress.getByName("127.0.0.1"))
+    }
+    private val scheme = if (secure) "wss" else "ws"
+    private val worker = thread(start = true, name = "ws-test-server") {
+        try {
+            server.accept().use { socket ->
+                val connection = TestWebSocketConnection(socket)
+                connection.handshake()
+                handler(connection)
+            }
+        } catch (_: Exception) {
+        }
+    }
+
+    val url: String = "$scheme://127.0.0.1:${server.localPort}/ws"
+
+    override fun close() {
+        server.close()
+        worker.join(2000)
+    }
+}
+
+internal class TestWebSocketConnection(socket: Socket) {
+    private val input = BufferedInputStream(socket.getInputStream())
+    private val output = BufferedOutputStream(socket.getOutputStream())
+    val requestHeaders = linkedMapOf<String, String>()
+
+    fun handshake() {
+        val requestLine = input.readAsciiLine() ?: error("missing websocket request line")
+        require(requestLine.startsWith("GET ")) { "unexpected request: $requestLine" }
+        while (true) {
+            val line = input.readAsciiLine() ?: error("unexpected EOF during websocket handshake")
+            if (line.isEmpty()) break
+            val colon = line.indexOf(':')
+            if (colon > 0) {
+                requestHeaders[line.substring(0, colon).trim().lowercase()] = line.substring(colon + 1).trim()
+            }
+        }
+        val key = requestHeaders["sec-websocket-key"] ?: error("missing Sec-WebSocket-Key")
+        val accept = Base64.getEncoder().encodeToString(
+            MessageDigest.getInstance("SHA-1")
+                .digest((key + "258EAFA5-E914-47DA-95CA-C5AB0DC85B11").toByteArray())
+        )
+        output.write(
+            (
+                "HTTP/1.1 101 Switching Protocols\r\n" +
+                    "Upgrade: websocket\r\n" +
+                    "Connection: Upgrade\r\n" +
+                    "Sec-WebSocket-Accept: $accept\r\n" +
+                    "\r\n"
+                ).toByteArray()
+        )
+        output.flush()
+    }
+
+    fun receiveText(): String = receiveFrame().let { frame ->
+        require(frame.opcode == 0x1) { "expected text frame, got opcode=${frame.opcode}" }
+        frame.payload.decodeToString()
+    }
+
+    fun receiveBinary(): ByteArray = receiveFrame().let { frame ->
+        require(frame.opcode == 0x2) { "expected binary frame, got opcode=${frame.opcode}" }
+        frame.payload
+    }
+
+    fun sendText(text: String) {
+        sendFrame(0x1, text.encodeToByteArray())
+    }
+
+    fun sendBinary(data: ByteArray) {
+        sendFrame(0x2, data)
+    }
+
+    fun close(code: Int = 1000, reason: String = "") {
+        val reasonBytes = reason.encodeToByteArray()
+        val payload = ByteArray(2 + reasonBytes.size)
+        payload[0] = ((code shr 8) and 0xff).toByte()
+        payload[1] = (code and 0xff).toByte()
+        reasonBytes.copyInto(payload, 2)
+        sendFrame(0x8, payload)
+    }
+
+    private fun sendFrame(opcode: Int, payload: ByteArray) {
+        output.write(0x80 or opcode)
+        when {
+            payload.size < 126 -> output.write(payload.size)
+            payload.size <= 0xffff -> {
+                output.write(126)
+                output.write((payload.size ushr 8) and 0xff)
+                output.write(payload.size and 0xff)
+            }
+            else -> error("payload too large for test websocket server")
+        }
+        output.write(payload)
+        output.flush()
+    }
+
+    private fun receiveFrame(): IncomingFrame {
+        val b0 = input.read()
+        require(b0 >= 0) { "unexpected EOF reading websocket frame" }
+        val b1 = input.read()
+        require(b1 >= 0) { "unexpected EOF reading websocket frame length" }
+        val opcode = b0 and 0x0f
+        var length = b1 and 0x7f
+        if (length == 126) {
+            length = (input.read() shl 8) or input.read()
+        } else if (length == 127) {
+            error("64-bit websocket lengths are not supported in tests")
+        }
+        val masked = (b1 and 0x80) != 0
+        val mask = if (masked) ByteArray(4).also { input.readFully(it) } else null
+        val payload = ByteArray(length)
+        input.readFully(payload)
+        if (mask != null) {
+            for (i in payload.indices) payload[i] = (payload[i].toInt() xor mask[i % 4].toInt()).toByte()
+        }
+        return IncomingFrame(opcode, payload)
+    }
+}
+
+private data class IncomingFrame(val opcode: Int, val payload: ByteArray)
+
+private fun BufferedInputStream.readAsciiLine(): String? {
+    val out = StringBuilder()
+    while (true) {
+        val b = read()
+        if (b < 0) return if (out.isEmpty()) null else out.toString()
+        if (b == '\n'.code) {
+            if (out.endsWith("\r")) out.setLength(out.length - 1)
+            return out.toString()
+        }
+        out.append(b.toChar())
+    }
+}
+
+private fun BufferedInputStream.readFully(target: ByteArray) {
+    var offset = 0
+    while (offset < target.size) {
+        val read = read(target, offset, target.size - offset)
+        require(read > 0) { "unexpected EOF" }
+        offset += read
+    }
+}

lyngio/src/linuxMain/kotlin/net/sergeych/lyngio/http/PlatformLinux.kt

@@ -0,0 +1,5 @@
+package net.sergeych.lyngio.http
+
+import io.ktor.client.engine.curl.Curl
+
+actual fun getSystemHttpEngine(): LyngHttpEngine = createKtorHttpEngine(Curl)

lyngio/src/linuxMain/kotlin/net/sergeych/lyngio/net/PlatformLinux.kt

@@ -0,0 +1,8 @@
+package net.sergeych.lyngio.net
+
+actual fun getSystemNetEngine(): LyngNetEngine = createNativeKtorNetEngine(
+    isSupported = true,
+    isTcpAvailable = true,
+    isTcpServerAvailable = true,
+    isUdpAvailable = true,
+)

lyngio/src/linuxMain/kotlin/net/sergeych/lyngio/ws/PlatformLinux.kt

@@ -0,0 +1,5 @@
+package net.sergeych.lyngio.ws
+
+import io.ktor.client.engine.curl.Curl
+
+actual fun getSystemWsEngine(): LyngWsEngine = createKtorWsEngine(Curl)

lyngio/src/linuxTest/kotlin/net/sergeych/lyngio/net/NetLinuxNativeTest.kt

@@ -0,0 +1,90 @@
+package net.sergeych.lyngio.net
+
+import kotlinx.coroutines.async
+import kotlinx.coroutines.runBlocking
+import kotlinx.coroutines.withTimeout
+import net.sergeych.lyng.Compiler
+import net.sergeych.lyng.Script
+import net.sergeych.lyng.io.net.createNetModule
+import net.sergeych.lyngio.net.security.PermitAllNetAccessPolicy
+import kotlin.test.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertTrue
+
+class NetLinuxNativeTest {
+
+    @Test
+    fun testLinuxNativeCapabilitiesAndResolve() = runBlocking {
+        val engine = getSystemNetEngine()
+
+        assertTrue(engine.isSupported)
+        assertTrue(engine.isTcpAvailable)
+        assertTrue(engine.isTcpServerAvailable)
+        assertTrue(engine.isUdpAvailable)
+
+        val resolved = engine.resolve("127.0.0.1", 4040)
+        assertEquals(1, resolved.size)
+        assertEquals("127.0.0.1", resolved.single().host)
+        assertEquals(4040, resolved.single().port)
+        assertEquals(LyngIpVersion.IPV4, resolved.single().ipVersion)
+        assertTrue(resolved.single().resolved)
+    }
+
+    @Test
+    fun testLinuxNativeLyngModuleCapabilities() = runBlocking {
+        val scope = Script.newScope()
+        createNetModule(PermitAllNetAccessPolicy, scope)
+
+        val code = """
+            import lyng.io.net
+
+            val a: SocketAddress = Net.resolve("127.0.0.1", 4040)[0]
+            [Net.isSupported(), Net.isTcpAvailable(), Net.isTcpServerAvailable(), Net.isUdpAvailable(), a.toString(), a.resolved]
+        """.trimIndent()
+
+        val result = Compiler.compile(code).execute(scope).inspect(scope)
+        assertTrue(result.contains("true,true,true,true"), result)
+        assertTrue(result.contains("127.0.0.1:4040"), result)
+    }
+
+    @Test
+    fun testLinuxNativeTcpAndUdpLoopback() = runBlocking {
+        val engine = getSystemNetEngine()
+
+        withTimeout(5_000) {
+            val server = engine.tcpListen(host = "127.0.0.1", port = 0, backlog = 16, reuseAddress = true)
+            val accepted = async {
+                val client = server.accept()
+                val text = client.read(4)?.decodeToString()
+                client.writeUtf8("echo:$text")
+                client.flush()
+                client.close()
+                server.close()
+                text
+            }
+
+            val socket = engine.tcpConnect("127.0.0.1", server.localAddress().port, timeoutMillis = 2_000, noDelay = true)
+            socket.writeUtf8("ping")
+            socket.flush()
+            val reply = socket.read(32)?.decodeToString()
+            socket.close()
+
+            assertEquals("ping", accepted.await())
+            assertEquals("echo:ping", reply)
+        }
+
+        withTimeout(5_000) {
+            val receiver = engine.udpBind(host = "127.0.0.1", port = 0, reuseAddress = true)
+            val sender = engine.udpBind(host = "127.0.0.1", port = 0, reuseAddress = true)
+
+            sender.send("ping".encodeToByteArray(), "127.0.0.1", receiver.localAddress().port)
+            val datagram = receiver.receive(32)
+
+            sender.close()
+            receiver.close()
+
+            assertEquals("ping", datagram?.data?.decodeToString())
+            assertTrue((datagram?.address?.port ?: 0) > 0)
+        }
+    }
+}

lyngio/src/mingwMain/kotlin/net/sergeych/lyngio/http/PlatformMingw.kt

@@ -0,0 +1,5 @@
+package net.sergeych.lyngio.http
+
+import io.ktor.client.engine.winhttp.WinHttp
+
+actual fun getSystemHttpEngine(): LyngHttpEngine = createKtorHttpEngine(WinHttp)

lyngio/src/mingwMain/kotlin/net/sergeych/lyngio/net/PlatformMingw.kt

@@ -0,0 +1,3 @@
+package net.sergeych.lyngio.net
+
+actual fun getSystemNetEngine(): LyngNetEngine = UnsupportedLyngNetEngine

lyngio/src/mingwMain/kotlin/net/sergeych/lyngio/ws/PlatformMingw.kt

@@ -0,0 +1,5 @@
+package net.sergeych.lyngio.ws
+
+import io.ktor.client.engine.winhttp.WinHttp
+
+actual fun getSystemWsEngine(): LyngWsEngine = createKtorWsEngine(WinHttp)

lyngio/src/nativeMain/kotlin/net/sergeych/lyngio/net/NativeKtorNetEngine.kt

@@ -0,0 +1,216 @@
+package net.sergeych.lyngio.net
+
+import io.ktor.network.selector.SelectorManager
+import io.ktor.network.sockets.BoundDatagramSocket
+import io.ktor.network.sockets.Datagram
+import io.ktor.network.sockets.InetSocketAddress
+import io.ktor.network.sockets.ServerSocket
+import io.ktor.network.sockets.Socket
+import io.ktor.network.sockets.SocketAddress
+import io.ktor.network.sockets.aSocket
+import io.ktor.network.sockets.isClosed
+import io.ktor.network.sockets.openReadChannel
+import io.ktor.network.sockets.openWriteChannel
+import io.ktor.utils.io.ByteReadChannel
+import io.ktor.utils.io.ByteWriteChannel
+import io.ktor.utils.io.readAvailable
+import io.ktor.utils.io.readUTF8Line
+import io.ktor.utils.io.writeFully
+import io.ktor.utils.io.writeStringUtf8
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.withTimeout
+import kotlinx.io.Buffer
+import kotlinx.io.readByteArray
+
+internal fun createNativeKtorNetEngine(
+    isSupported: Boolean,
+    isTcpAvailable: Boolean,
+    isTcpServerAvailable: Boolean,
+    isUdpAvailable: Boolean,
+): LyngNetEngine = NativeKtorNetEngine(
+    isSupported = isSupported,
+    isTcpAvailable = isTcpAvailable,
+    isTcpServerAvailable = isTcpServerAvailable,
+    isUdpAvailable = isUdpAvailable,
+)
+
+private class NativeKtorNetEngine(
+    override val isSupported: Boolean,
+    override val isTcpAvailable: Boolean,
+    override val isTcpServerAvailable: Boolean,
+    override val isUdpAvailable: Boolean,
+) : LyngNetEngine {
+    private val selectorManager: SelectorManager by lazy { SelectorManager(Dispatchers.Default) }
+
+    override suspend fun resolve(host: String, port: Int): List<LyngSocketAddress> {
+        val rawAddress = InetSocketAddress(host, port).resolveAddress()
+            ?: throw IllegalStateException("Failed to resolve address for $host")
+        return listOf(
+            LyngSocketAddress(
+                host = rawAddress.toIpHostString(),
+                port = port,
+                ipVersion = rawAddress.toLyngIpVersion(),
+                resolved = true,
+            )
+        )
+    }
+
+    override suspend fun tcpConnect(
+        host: String,
+        port: Int,
+        timeoutMillis: Long?,
+        noDelay: Boolean,
+    ): LyngTcpSocket {
+        val connectBlock: suspend () -> Socket = {
+            aSocket(selectorManager).tcp().connect(host, port) {
+                this.noDelay = noDelay
+            }
+        }
+        val socket = if (timeoutMillis != null) withTimeout(timeoutMillis) { connectBlock() } else connectBlock()
+        return NativeLyngTcpSocket(socket)
+    }
+
+    override suspend fun tcpListen(
+        host: String?,
+        port: Int,
+        backlog: Int,
+        reuseAddress: Boolean,
+    ): LyngTcpServer {
+        val bindHost = host ?: "0.0.0.0"
+        val server = aSocket(selectorManager).tcp().bind(bindHost, port) {
+            backlogSize = backlog
+            this.reuseAddress = reuseAddress
+        }
+        return NativeLyngTcpServer(server)
+    }
+
+    override suspend fun udpBind(host: String?, port: Int, reuseAddress: Boolean): LyngUdpSocket {
+        val bindHost = host ?: "0.0.0.0"
+        val socket = aSocket(selectorManager).udp().bind(bindHost, port) {
+            this.reuseAddress = reuseAddress
+        }
+        return NativeLyngUdpSocket(socket)
+    }
+}
+
+private class NativeLyngTcpSocket(
+    private val socket: Socket,
+) : LyngTcpSocket {
+    private val input: ByteReadChannel by lazy { socket.openReadChannel() }
+    private val output: ByteWriteChannel by lazy { socket.openWriteChannel(autoFlush = true) }
+
+    override fun isOpen(): Boolean = !socket.isClosed
+
+    override fun localAddress(): LyngSocketAddress = socket.localAddress.toLyngSocketAddress(resolved = true)
+
+    override fun remoteAddress(): LyngSocketAddress = socket.remoteAddress.toLyngSocketAddress(resolved = true)
+
+    override suspend fun read(maxBytes: Int): ByteArray? {
+        if (!input.awaitContent(1)) return null
+        val buffer = ByteArray(maxBytes)
+        val count = input.readAvailable(buffer, 0, maxBytes)
+        return when {
+            count <= 0 -> null
+            count == maxBytes -> buffer
+            else -> buffer.copyOf(count)
+        }
+    }
+
+    override suspend fun readLine(): String? = input.readUTF8Line()
+
+    override suspend fun write(data: ByteArray) {
+        output.writeFully(data, 0, data.size)
+    }
+
+    override suspend fun writeUtf8(text: String) {
+        output.writeStringUtf8(text)
+    }
+
+    override suspend fun flush() {
+        output.flush()
+    }
+
+    override fun close() {
+        socket.close()
+    }
+}
+
+private class NativeLyngTcpServer(
+    private val server: ServerSocket,
+) : LyngTcpServer {
+    override fun isOpen(): Boolean = !server.isClosed
+
+    override fun localAddress(): LyngSocketAddress = server.localAddress.toLyngSocketAddress(resolved = true)
+
+    override suspend fun accept(): LyngTcpSocket = NativeLyngTcpSocket(server.accept())
+
+    override fun close() {
+        server.close()
+    }
+}
+
+private class NativeLyngUdpSocket(
+    private val socket: BoundDatagramSocket,
+) : LyngUdpSocket {
+    override fun isOpen(): Boolean = !socket.isClosed
+
+    override fun localAddress(): LyngSocketAddress = socket.localAddress.toLyngSocketAddress(resolved = true)
+
+    override suspend fun receive(maxBytes: Int): LyngDatagram? {
+        val datagram = try {
+            socket.receive()
+        } catch (e: Throwable) {
+            if (!isOpen()) return null
+            throw e
+        }
+        val bytes = datagram.packet.readByteArray().let {
+            if (it.size <= maxBytes) it else it.copyOf(maxBytes)
+        }
+        return LyngDatagram(bytes, datagram.address.toLyngSocketAddress(resolved = true))
+    }
+
+    override suspend fun send(data: ByteArray, host: String, port: Int) {
+        val packet = Buffer()
+        packet.write(data)
+        socket.send(Datagram(packet, InetSocketAddress(host, port)))
+    }
+
+    override fun close() {
+        socket.close()
+    }
+}
+
+private fun SocketAddress.toLyngSocketAddress(resolved: Boolean): LyngSocketAddress {
+    val inetAddress = this as? InetSocketAddress
+    if (inetAddress != null) {
+        val rawAddress = inetAddress.resolveAddress()
+        val host = rawAddress?.toIpHostString() ?: inetAddress.hostname
+        return LyngSocketAddress(
+            host = host,
+            port = inetAddress.port,
+            ipVersion = rawAddress?.toLyngIpVersion()
+                ?: if (host.contains(':')) LyngIpVersion.IPV6 else LyngIpVersion.IPV4,
+            resolved = resolved,
+        )
+    }
+
+    val rendered = toString()
+    return LyngSocketAddress(
+        host = rendered,
+        port = 0,
+        ipVersion = if (rendered.contains(':')) LyngIpVersion.IPV6 else LyngIpVersion.IPV4,
+        resolved = resolved,
+    )
+}
+
+private fun ByteArray.toLyngIpVersion(): LyngIpVersion = if (size == 16) LyngIpVersion.IPV6 else LyngIpVersion.IPV4
+
+private fun ByteArray.toIpHostString(): String = when (size) {
+    4 -> joinToString(".") { (it.toInt() and 0xff).toString() }
+    16 -> (0 until 8).joinToString(":") { index ->
+        val hi = this[index * 2].toInt() and 0xff
+        val lo = this[index * 2 + 1].toInt() and 0xff
+        ((hi shl 8) or lo).toString(16)
+    }
+    else -> error("Unsupported IP address length: $size")
+}

lyngio/stdlib/lyng/io/http.lyng

@@ -0,0 +1,72 @@
+package lyng.io.http
+
+/*
+    Response/header view that behaves like a map for the first value of each header name.
+    Multi-valued headers are exposed through `getAll`.
+*/
+extern class HttpHeaders : Map<String, String> {
+    /* Return the first value for the given header name, or null when absent. */
+    fun get(name: String): String?
+    /* Return all values for the given header name, preserving wire order when available. */
+    fun getAll(name: String): List<String>
+    /* Return distinct header names present in this response. */
+    fun names(): List<String>
+}
+
+/* Mutable request descriptor for programmatic HTTP calls. */
+extern class HttpRequest {
+    /* Request method, e.g. GET, POST, PUT, DELETE. */
+    var method: String
+    /* Absolute URL including scheme. */
+    var url: String
+    /* Simple request headers map. */
+    var headers: Map<String, String>
+    /* Optional UTF-8 request body. */
+    var bodyText: String?
+    /* Optional binary request body. */
+    var bodyBytes: Buffer?
+    /* Optional total request timeout in milliseconds. */
+    var timeoutMillis: Int?
+}
+
+/* HTTP response snapshot with cached body accessors. */
+extern class HttpResponse {
+    /* Numeric status code, e.g. 200, 404, 500. */
+    val status: Int
+    /* Human-readable status text when available. */
+    val statusText: String
+    /* Response headers. */
+    val headers: HttpHeaders
+    /* Decode response body as text. Cached after first call. */
+    fun text(): String
+    /* Return response body as bytes. Cached after first call. */
+    fun bytes(): Buffer
+}
+
+/* HTTP/HTTPS client singleton. */
+extern object Http {
+    /* True when HTTP client support is available on this runtime. */
+    fun isSupported(): Bool
+
+    /* Execute a request described by `HttpRequest`. */
+    fun request(req: HttpRequest): HttpResponse
+
+    /*
+        Convenience GET request.
+        `headers...` accepts `MapEntry` values such as `"Accept" => "text/plain"`
+        and 2-item lists such as `["Accept", "text/plain"]`.
+    */
+    fun get(url: String, headers...): HttpResponse
+
+    /*
+        Convenience POST request with UTF-8 body text.
+        `headers...` follows the same rules as `get`.
+    */
+    fun post(url: String, bodyText: String = "", contentType: String? = null, headers...): HttpResponse
+
+    /*
+        Convenience POST request with binary body.
+        `headers...` follows the same rules as `get`.
+    */
+    fun postBytes(url: String, body: Buffer, contentType: String? = null, headers...): HttpResponse
+}

lyngio/stdlib/lyng/io/net.lyng

@@ -0,0 +1,113 @@
+package lyng.io.net
+
+/* Address family for resolved or bound endpoints. */
+enum IpVersion {
+    IPV4,
+    IPV6
+}
+
+/* Concrete socket endpoint. */
+extern class SocketAddress {
+    /* Numeric or host-form address string. */
+    val host: String
+    /* Transport port number. */
+    val port: Int
+    /* Address family. */
+    val ipVersion: IpVersion
+    /* True when obtained from DNS resolution rather than raw bind input. */
+    val resolved: Bool
+    /* Stable printable form such as `127.0.0.1:4040` or `[::1]:4040`. */
+    override fun toString(): String
+}
+
+/* Datagram payload paired with sender/peer address. */
+extern class Datagram {
+    val data: Buffer
+    val address: SocketAddress
+}
+
+/* Connected TCP socket. */
+extern class TcpSocket {
+    /* True while the socket remains open. */
+    fun isOpen(): Bool
+    /* Local bound address after connect/bind. */
+    fun localAddress(): SocketAddress
+    /* Connected peer address. */
+    fun remoteAddress(): SocketAddress
+    /* Read up to `maxBytes`; returns null on clean EOF before any data. */
+    fun read(maxBytes: Int = 65536): Buffer?
+    /* Read one UTF-8 line without trailing newline; null on clean EOF. */
+    fun readLine(): String?
+    /* Write all bytes from the buffer. */
+    fun write(data: Buffer): void
+    /* Write UTF-8 encoded text. */
+    fun writeUtf8(text: String): void
+    /* Flush buffered output if needed by the backend. */
+    fun flush(): void
+    /* Close the socket. */
+    fun close(): void
+}
+
+/* Listening TCP server socket. */
+extern class TcpServer {
+    /* True while the listening socket remains open. */
+    fun isOpen(): Bool
+    /* Actual local bind address. */
+    fun localAddress(): SocketAddress
+    /* Accept next incoming client connection. */
+    fun accept(): TcpSocket
+    /* Close the listening socket. */
+    fun close(): void
+}
+
+/* Bound UDP socket. */
+extern class UdpSocket {
+    /* True while the socket remains open. */
+    fun isOpen(): Bool
+    /* Actual local bind address. */
+    fun localAddress(): SocketAddress
+    /* Receive one datagram up to `maxBytes`, or null on clean shutdown. */
+    fun receive(maxBytes: Int = 65536): Datagram?
+    /* Send one datagram to the provided host and port. */
+    fun send(data: Buffer, host: String, port: Int): void
+    /* Close the socket. */
+    fun close(): void
+}
+
+/* Raw transport networking singleton. */
+extern object Net {
+    /* True when at least one transport feature is implemented on this runtime. */
+    fun isSupported(): Bool
+    /* True when outbound TCP client sockets are available. */
+    fun isTcpAvailable(): Bool
+    /* True when listening TCP server sockets are available. */
+    fun isTcpServerAvailable(): Bool
+    /* True when UDP datagram sockets are available. */
+    fun isUdpAvailable(): Bool
+
+    /* Resolve host name and port into concrete addresses. */
+    fun resolve(host: String, port: Int): List<SocketAddress>
+
+    /* Connect outbound TCP socket. */
+    fun tcpConnect(
+        host: String,
+        port: Int,
+        timeoutMillis: Int? = null,
+        noDelay: Bool = true
+    ): TcpSocket
+
+    /* Start listening TCP server socket. */
+    fun tcpListen(
+        port: Int,
+        host: String? = null,
+        backlog: Int = 128,
+        reuseAddress: Bool = true
+    ): TcpServer
+
+    /* Bind UDP socket, using an ephemeral port by default. */
+    fun udpBind(
+        port: Int = 0,
+        host: String? = null,
+        reuseAddress: Bool = true
+    ): UdpSocket
+}

lyngio/stdlib/lyng/io/ws.lyng

@@ -0,0 +1,40 @@
+package lyng.io.ws
+
+/* Received WebSocket message. */
+extern class WsMessage {
+    /* True when this message carries text payload. */
+    val isText: Bool
+    /* Text payload for text messages, otherwise null. */
+    val text: String?
+    /* Binary payload for binary messages, otherwise null. */
+    val data: Buffer?
+}
+
+/* Active WebSocket client session. */
+extern class WsSession {
+    /* True while the session remains open. */
+    fun isOpen(): Bool
+    /* Connected URL string. */
+    fun url(): String
+    /* Send a text message. */
+    fun sendText(text: String): void
+    /* Send a binary message. */
+    fun sendBytes(data: Buffer): void
+    /* Receive next message, or null on clean close. */
+    fun receive(): WsMessage?
+    /* Close the session with optional status code and reason. */
+    fun close(code: Int = 1000, reason: String = ""): void
+}
+
+/* WebSocket client singleton. */
+extern object Ws {
+    /* True when WebSocket client support is available on this runtime. */
+    fun isSupported(): Bool
+
+    /*
+        Open a client WebSocket session.
+        `headers...` accepts `MapEntry` values such as `"Authorization" => "Bearer x"`
+        and 2-item lists such as `["Authorization", "Bearer x"]`.
+    */
+    fun connect(url: String, headers...): WsSession
+}

lynglib/build.gradle.kts

@@ -21,7 +21,7 @@ import org.jetbrains.kotlin.gradle.ExperimentalWasmDsl
 import org.jetbrains.kotlin.gradle.dsl.JvmTarget
 
 group = "net.sergeych"
-version = "1.5.3"
+version = "1.5.4-SNAPSHOT"
 
 // Removed legacy buildscript classpath declarations; plugins are applied via the plugins DSL below
 

lynglib/src/commonMain/kotlin/net/sergeych/lyng/Compiler.kt

@@ -4532,6 +4532,15 @@ class Compiler(
         }
     }
 
+    private fun inferForLoopElementType(source: Statement, constRange: ConstIntRange?): TypeDecl? {
+        if (constRange != null) return TypeDecl.Simple("Int", false)
+        val sourceType = inferTypeDeclFromInitializer(source) ?: return null
+        return when {
+            isRangeType(sourceType) -> TypeDecl.Simple("Int", false)
+            else -> inferCollectionElementType(expandTypeAliases(sourceType, source.pos))
+        }
+    }
+
     private fun typeDeclSubtypeOf(arg: TypeDecl, param: TypeDecl): Boolean {
         if (param == TypeDecl.TypeAny || param == TypeDecl.TypeNullableAny) return true
         val (argBase, argNullable) = stripNullable(arg)
@@ -4934,12 +4943,33 @@ class Compiler(
 
     private fun inferCallReturnClass(ref: CallRef): ObjClass? {
         return when (val target = ref.target) {
-            is LocalSlotRef -> callableReturnTypeByScopeId[target.scopeId]?.get(target.slot)
+            is LocalSlotRef -> when (target.name) {
-                ?: resolveClassByName(target.name)
+                "lazy" -> resolveClassByName("lazy")
-            is LocalVarRef -> callableReturnTypeByName[target.name]
+                "iterator" -> ObjIterator
-                ?: resolveClassByName(target.name)
+                "flow" -> ObjFlow.type
-            is FastLocalVarRef -> callableReturnTypeByName[target.name]
+                "launch" -> ObjDeferred.type
-                ?: resolveClassByName(target.name)
+                "dynamic" -> ObjDynamic.type
+                else -> callableReturnTypeByScopeId[target.scopeId]?.get(target.slot)
+                    ?: resolveClassByName(target.name)
+            }
+            is LocalVarRef -> when (target.name) {
+                "lazy" -> resolveClassByName("lazy")
+                "iterator" -> ObjIterator
+                "flow" -> ObjFlow.type
+                "launch" -> ObjDeferred.type
+                "dynamic" -> ObjDynamic.type
+                else -> callableReturnTypeByName[target.name]
+                    ?: resolveClassByName(target.name)
+            }
+            is FastLocalVarRef -> when (target.name) {
+                "lazy" -> resolveClassByName("lazy")
+                "iterator" -> ObjIterator
+                "flow" -> ObjFlow.type
+                "launch" -> ObjDeferred.type
+                "dynamic" -> ObjDynamic.type
+                else -> callableReturnTypeByName[target.name]
+                    ?: resolveClassByName(target.name)
+            }
             is ConstRef -> when (val value = target.constValue) {
                 is ObjClass -> value
                 is ObjString -> ObjString.type
@@ -7490,6 +7520,20 @@ class Compiler(
             val loopSlotPlan = SlotPlan(mutableMapOf(), 0, nextScopeId++)
             slotPlanStack.add(loopSlotPlan)
             declareSlotName(tVar.value, isMutable = true, isDelegated = false)
+            val loopSlotIndex = loopSlotPlan.slots[tVar.value]?.index
+            val loopVarTypeDecl = inferForLoopElementType(source, constRange)
+            val hadLoopNameType = nameTypeDecl.containsKey(tVar.value)
+            val prevLoopNameType = nameTypeDecl[tVar.value]
+            val hadLoopNameClass = nameObjClass.containsKey(tVar.value)
+            val prevLoopNameClass = nameObjClass[tVar.value]
+            if (loopSlotIndex != null && loopVarTypeDecl != null) {
+                slotTypeDeclByScopeId.getOrPut(loopSlotPlan.id) { mutableMapOf() }[loopSlotIndex] = loopVarTypeDecl
+                nameTypeDecl[tVar.value] = loopVarTypeDecl
+                resolveTypeDeclObjClass(loopVarTypeDecl)?.let { loopVarClass ->
+                    slotTypeByScopeId.getOrPut(loopSlotPlan.id) { mutableMapOf() }[loopSlotIndex] = loopVarClass
+                    nameObjClass[tVar.value] = loopVarClass
+                }
+            }
             val (canBreak, body, elseStatement) = try {
                 resolutionSink?.enterScope(ScopeKind.BLOCK, tVar.pos, null)
                 resolutionSink?.declareSymbol(tVar.value, SymbolKind.LOCAL, isMutable = true, pos = tVar.pos)
@@ -7509,6 +7553,16 @@ class Compiler(
                     Triple(loopParsed.first, loopParsed.second, elseStmt)
                 }
             } finally {
+                if (hadLoopNameType) {
+                    nameTypeDecl[tVar.value] = prevLoopNameType!!
+                } else {
+                    nameTypeDecl.remove(tVar.value)
+                }
+                if (hadLoopNameClass) {
+                    nameObjClass[tVar.value] = prevLoopNameClass!!
+                } else {
+                    nameObjClass.remove(tVar.value)
+                }
                 resolutionSink?.exitScope(cc.currentPos())
                 slotPlanStack.removeLast()
             }
@@ -9164,7 +9218,6 @@ class Compiler(
                 varTypeDecl = inferred
             }
         }
-
         if (isDelegate && initialExpression != null) {
             ensureDelegateType(initialExpression)
             val lazyClass = resolveClassByName("lazy")

lynglib/src/commonTest/kotlin/CoroutinesTest.kt

@@ -209,4 +209,26 @@ class TestCoroutines {
 //            }.toList())
         """.trimIndent())
     }
+
+    @Test
+    fun testInferenceList() = runTest {
+        eval("""
+            import lyng.time
+
+            val d1 = launch {
+                delay(1000.milliseconds)
+                "Task A finished"
+            }
+            val d2 = launch {
+                delay(500.milliseconds)
+                "Task B finished"
+            }
+            val foo = [d1, d2]
+            for (d in foo) {
+                d.await()
+                println(d)
+            }
+
+        """.trimIndent())
+    }
 }

lynglib/src/commonTest/kotlin/ScriptTest.kt

@@ -2050,9 +2050,9 @@ class ScriptTest {
     fun nationalCharsTest() = runTest {
         eval(
             """
-            fun сумма_ряда(x, погрешность=0.0001, f) {
+            fun сумма_ряда(x, погрешность=0.001, f) {
                 var сумма = 0
-                for( n in 1..100000) {
+                for( n in 1..5000) {
                     val следующая_сумма = сумма + f(x, n)
                     if( n > 1 && abs(следующая_сумма - сумма) < погрешность )
                         break следующая_сумма

lynglib/src/commonTest/kotlin/net/sergeych/lyng/ComplexModuleTest.kt

@@ -97,15 +97,15 @@ class ComplexModuleTest {
             assert( 5 + 1.d.i is Complex )
             assert( 5.d + 1.i is Complex )
             assert( 5.d + 2.d.i is Complex )
-            assertEquals("0.0+1.0i", 1.d.i.toString())
+            assert(1.d.i.toString() in ["0.0+1.0i", "0+1i"])
-            assertEquals("1.0+0.0i", 1.d.re.toString())
+            assert(1.d.re.toString() in ["1.0+0.0i", "1+0i"])
             
             var c = 1 + 2.i
             assert(c is Complex)
-            assertEquals("1.0+2.0i", c.toString())
+            assert(c.toString() in ["1.0+2.0i", "1+2i"])
         
             c = 1.d + 2.i
-            assertEquals("1.0+2.0i", c.toString())
+            assert(c.toString() in ["1.0+2.0i", "1+2i"])
         """.trimIndent()
         )
     }

notes/networking_handoff_2026-04-02.md

@@ -0,0 +1,205 @@
+# Networking Handoff
+
+Date: 2026-04-02
+Commit: `5346d15` (`Add KMP networking backends`)
+
+## Scope completed
+
+The `lyngio` networking work now provides a uniform Lyng-facing API with capability probes and platform-specific implementations.
+
+Implemented modules:
+
+- `lyng.io.http`
+- `lyng.io.ws`
+- `lyng.io.net`
+
+## Current support matrix
+
+### HTTP / HTTPS
+
+- JVM: supported
+- Android: supported
+- JS: supported
+- Linux Native: supported
+- Windows Native (`mingwX64`): supported
+- Apple Native: compile-verified on this Linux host
+
+### WS / WSS
+
+- JVM: supported
+- Android: supported
+- JS: supported
+- Linux Native: supported
+- Windows Native (`mingwX64`): supported
+- Apple Native: compile-verified on this Linux host
+
+### Raw networking (`lyng.io.net`)
+
+- JVM: supported
+- Android: supported
+- JS/Node: supported
+- JS/browser: unsupported by capability probe
+- Linux Native: supported
+- Apple Native: enabled via shared native backend; compile-verified, runtime not yet host-verified
+- Other Native targets: intentionally still unsupported
+
+## Important design decisions
+
+- Ktor is the backend for all currently implemented networking.
+- API is uniform across targets; platform variance is exposed through capability checks such as:
+  - `Http.isSupported()`
+  - `Ws.isSupported()`
+  - `Net.isSupported()`
+  - `Net.isTcpAvailable()`
+  - `Net.isTcpServerAvailable()`
+  - `Net.isUdpAvailable()`
+- Native support was restricted to what matches Ktor client-engine support:
+  - Darwin for Apple Native
+  - Curl for Linux Native
+  - WinHttp for Windows Native
+- Native raw sockets use a shared Ktor socket implementation for Linux and Darwin source sets.
+- Capability probes are enabled on Linux Native and Apple Native; Apple Native is compile-verified but not yet runtime-tested on a macOS host.
+
+## Documentation and tests status
+
+Docs updated:
+
+- `docs/lyng.io.http.md`
+- `docs/lyng.io.ws.md`
+- `docs/lyng.io.net.md`
+
+Verified docs/tests:
+
+- HTTP/HTTPS docs are covered with extracted markdown tests on JVM.
+- WS/WSS docs are covered with extracted markdown tests on JVM.
+- JS/Node has both engine-level and Lyng-module-level tests for raw networking.
+
+## Key implementation files
+
+Shared:
+
+- `lyngio/src/commonMain/kotlin/net/sergeych/lyngio/http/LyngHttp.kt`
+- `lyngio/src/commonMain/kotlin/net/sergeych/lyng/io/http/LyngHttpModule.kt`
+- `lyngio/src/commonMain/kotlin/net/sergeych/lyngio/ws/LyngWs.kt`
+- `lyngio/src/commonMain/kotlin/net/sergeych/lyngio/net/LyngNet.kt`
+- `lyngio/build.gradle.kts`
+- `gradle/libs.versions.toml`
+
+Platform HTTP:
+
+- `lyngio/src/jvmMain/kotlin/net/sergeych/lyngio/http/PlatformJvm.kt`
+- `lyngio/src/jsMain/kotlin/net/sergeych/lyngio/http/PlatformJs.kt`
+- `lyngio/src/androidMain/kotlin/net/sergeych/lyngio/http/PlatformAndroid.kt`
+- `lyngio/src/darwinMain/kotlin/net/sergeych/lyngio/http/PlatformDarwin.kt`
+- `lyngio/src/linuxMain/kotlin/net/sergeych/lyngio/http/PlatformLinux.kt`
+- `lyngio/src/mingwMain/kotlin/net/sergeych/lyngio/http/PlatformMingw.kt`
+
+Platform WS:
+
+- `lyngio/src/jvmMain/kotlin/net/sergeych/lyngio/ws/PlatformJvm.kt`
+- `lyngio/src/jsMain/kotlin/net/sergeych/lyngio/ws/PlatformJs.kt`
+- `lyngio/src/androidMain/kotlin/net/sergeych/lyngio/ws/PlatformAndroid.kt`
+- `lyngio/src/darwinMain/kotlin/net/sergeych/lyngio/ws/PlatformDarwin.kt`
+- `lyngio/src/linuxMain/kotlin/net/sergeych/lyngio/ws/PlatformLinux.kt`
+- `lyngio/src/mingwMain/kotlin/net/sergeych/lyngio/ws/PlatformMingw.kt`
+
+Platform raw net:
+
+- `lyngio/src/jvmMain/kotlin/net/sergeych/lyngio/net/PlatformJvm.kt`
+- `lyngio/src/jsMain/kotlin/net/sergeych/lyngio/net/PlatformJs.kt`
+- `lyngio/src/androidMain/kotlin/net/sergeych/lyngio/net/PlatformAndroid.kt`
+- `lyngio/src/nativeMain/kotlin/net/sergeych/lyngio/net/NativeKtorNetEngine.kt`
+- `lyngio/src/linuxMain/kotlin/net/sergeych/lyngio/net/PlatformLinux.kt`
+- `lyngio/src/darwinMain/kotlin/net/sergeych/lyngio/net/PlatformDarwin.kt`
+- `lyngio/src/mingwMain/kotlin/net/sergeych/lyngio/net/PlatformMingw.kt`
+
+JS tests:
+
+- `lyngio/src/jsTest/kotlin/net/sergeych/lyngio/PlatformCapabilityJsTest.kt`
+- `lyngio/src/jsTest/kotlin/net/sergeych/lyngio/NetJsNodeTest.kt`
+- `lyngio/src/jsTest/kotlin/net/sergeych/lyng/io/net/LyngNetModuleJsNodeTest.kt`
+
+JVM tests:
+
+- `lyngio/src/jvmTest/kotlin/LyngioBookTest.kt`
+- `lyngio/src/jvmTest/kotlin/net/sergeych/lyng/io/http/LyngHttpModuleTest.kt`
+- `lyngio/src/jvmTest/kotlin/net/sergeych/lyng/io/ws/LyngWsModuleTest.kt`
+- `lyngio/src/jvmTest/kotlin/net/sergeych/lyng/io/net/LyngNetModuleTest.kt`
+
+Linux Native tests:
+
+- `lyngio/src/linuxTest/kotlin/net/sergeych/lyngio/net/NetLinuxNativeTest.kt`
+
+## Verification already run
+
+JVM / docs:
+
+- `./gradlew :lyngio:jvmTest --tests LyngioBookTest`
+- `./gradlew :lyngio:jvmTest --tests net.sergeych.lyng.io.http.LyngHttpModuleTest`
+- `./gradlew :lyngio:jvmTest --tests net.sergeych.lyng.io.ws.LyngWsModuleTest`
+- `./gradlew :lyngio:jvmTest --tests net.sergeych.lyng.io.net.LyngNetModuleTest`
+
+JS:
+
+- `./gradlew :lyngio:compileKotlinJs`
+- `./gradlew :lyngio:compileTestKotlinJs`
+- `./gradlew :lyngio:jsNodeTest`
+- `./gradlew kotlinUpgradeYarnLock`
+
+Android:
+
+- `./gradlew :lyngio:compileDebugKotlinAndroid`
+- `./gradlew :lyngio:compileReleaseKotlinAndroid`
+
+Native:
+
+- `./gradlew :lyngio:compileKotlinLinuxX64`
+- `./gradlew :lyngio:compileKotlinLinuxArm64`
+- `./gradlew :lyngio:compileKotlinMingwX64`
+- `./gradlew :lyngio:compileKotlinIosX64`
+- `./gradlew :lyngio:compileKotlinIosArm64`
+- `./gradlew :lyngio:compileKotlinIosSimulatorArm64`
+- `./gradlew :lyngio:compileKotlinMacosArm64`
+- `./gradlew :lyngio:compileTestKotlinLinuxX64`
+- `./gradlew :lyngio:compileTestKotlinLinuxArm64`
+- `./gradlew :lyngio:linkDebugTestLinuxX64`
+- `./gradlew :lyngio:linuxX64Test`
+- `./gradlew :lyngio:linuxX64Test --tests net.sergeych.lyngio.net.NetLinuxNativeTest`
+- `./gradlew :lyngio:linuxX64Test --tests net.sergeych.lyngio.net.NetLinuxNativeTest.testLinuxNativeTcpAndUdpLoopback`
+- `./lyngio/build/bin/linuxX64/debugTest/test.kexe --ktest_filter='net.sergeych.lyngio.net.NetLinuxNativeTest.*'`
+
+## Known intentional gaps
+
+- Native raw sockets are enabled on Linux Native and Apple Native.
+- Apple Native raw networking is enabled based on shared-backend compile verification; runtime verification on macOS is still pending.
+- No Android device/instrumented runtime tests were added; only compile verification was done.
+
+## Worktree state after commit
+
+Current HEAD:
+
+- `5346d15` `Add KMP networking backends`
+
+Unrelated remaining change:
+
+- `examples/tetris_console.lyng`
+
+That file was not touched by the networking work and was intentionally left out of the commit.
+
+## Recommended next steps
+
+1. Add Native raw socket support only per target that compiles and passes a smoke test.
+2. Keep capability probes `false` on non-Linux Native targets until each raw-socket backend is proven.
+3. If Apple Native work continues, compile Darwin targets on a macOS host before claiming support.
+4. Run a macOS-hosted runtime smoke test when available to verify the already-enabled Darwin backend.
+5. Optionally add Android runtime tests later; compile-only verification exists now.
+
+## Suggested first task for the next chat
+
+Continue Native raw `lyng.io.net` incrementally from the verified Linux baseline:
+
+- keep Linux Native enabled
+- keep Apple Native enabled unless runtime verification disproves the shared-backend assumption
+- keep other Native targets capability-gated off until compiled and smoke-tested
+- use only `ktor-network` support that actually compiles
+- do not change the Lyng-facing API

proposals/lyngio_network_module.md

@@ -0,0 +1,577 @@
+# Proposal: Ktor-Backed Networking Modules For `lyngio`
+
+Status: Draft  
+Date: 2026-04-02  
+Owner: `lyngio`
+
+## Context
+
+`lyngio` currently provides optional modules for filesystem, process execution, and console access. Networking is still missing.
+
+The first networking release should optimize for:
+
+- broad multiplatform reach from day one
+- a stable Lyng-native API surface
+- small implementation cost by building on existing, well-tested KMP libraries
+- explicit capability discovery, because not every transport exists on every platform
+
+The proposed implementation base is:
+
+- `io.ktor:ktor-client-*` for HTTP/HTTPS
+- Ktor WebSockets client on top of the HTTP client for `ws` and `wss`
+- `io.ktor:ktor-network` for TCP client/server sockets and UDP datagrams
+- no `ktor-server`
+
+The critical design constraint is that Lyng must not expose Ktor types directly. Ktor is an implementation dependency, not the public scripting model.
+
+## Goals
+
+- Add first-release networking support with a practical breadth of features:
+  - HTTP/HTTPS client
+  - WebSocket client (`ws` / `wss`)
+  - TCP client socket
+  - TCP server socket where supported
+  - UDP socket with a minimal datagram API where supported
+- Keep the Lyng-facing API uniform across platforms.
+- Provide capability discovery functions so scripts can branch safely.
+- Keep declarations in `.lyng` files as the source of truth.
+- Preserve room for later lower-level or non-universal socket APIs.
+
+## Non-goals (phase 1)
+
+- exposing Ktor classes, channels, frames, engines, or plugins directly to Lyng
+- HTTP server support
+- TLS configuration beyond default secure client behavior
+- fully general stream/channel APIs for every transport
+- advanced socket tuning beyond a minimal useful set
+- promising identical runtime support on every platform
+
+## Proposed module split
+
+Use three Lyng modules instead of one monolith:
+
+- `lyng.io.http`
+- `lyng.io.ws`
+- `lyng.io.net`
+
+Rationale:
+
+- HTTP and WebSocket are much more portable than raw sockets.
+- TCP/UDP belong in a transport module, not in the HTTP client API.
+- Each module can have its own capability checks while still sharing common address and security types underneath.
+- The user-facing import structure stays clear and unsurprising.
+
+## Uniform capability model
+
+Every module should expose explicit capability discovery.
+
+Recommended shape:
+
+- `Http.isSupported(): Bool`
+- `Ws.isSupported(): Bool`
+- `Net.isSupported(): Bool`
+- `Net.isTcpAvailable(): Bool`
+- `Net.isTcpServerAvailable(): Bool`
+- `Net.isUdpAvailable(): Bool`
+
+Optional richer form for later:
+
+- `Http.details(): HttpSupport`
+- `Ws.details(): WsSupport`
+- `Net.details(): NetSupport`
+
+For v1, booleans are enough.
+
+Scripts should be able to write:
+
+```lyng
+if (Net.isTcpServerAvailable()) {
+    val server = Net.tcpListen(4040)
+}
+```
+
+This is preferable to hard-failing during import or construction.
+
+## Design principles
+
+### 1. Lyng-native API, Ktor-backed implementation
+
+Public Lyng objects should be small and script-oriented.
+
+Do not expose:
+
+- `HttpClient`
+- `HttpResponse`
+- `ByteReadChannel`
+- `ByteWriteChannel`
+- `Frame`
+- Ktor engine names
+- Ktor pipeline/plugin concepts
+
+Instead, expose a narrow stable surface implemented internally via Ktor.
+
+### 2. Minimal but broad v1
+
+The first release should support more transport kinds, but only with the smallest coherent API for each kind.
+
+That means:
+
+- HTTP: request/response, headers, text/body bytes, status, method
+- WebSocket: connect, send text/binary, receive text/binary, close
+- TCP: connect, accept, read, write, close
+- UDP: bind, send datagram, receive datagram, close
+
+Notably absent from v1:
+
+- interceptors
+- cookies/session stores beyond defaults
+- multipart builders
+- HTTP/2 tuning knobs
+- ping/pong tuning for WebSockets
+- socket option explosion
+
+### 3. Uniform shapes where practical
+
+Across transports, prefer the same ideas:
+
+- `isOpen()`
+- `close()`
+- `localAddress()`
+- `remoteAddress()` when meaningful
+- `read(...)`, `write(...)`
+- `receive()`, `send(...)` for datagrams/messages
+- `isSupported()` / capability methods on module singletons
+
+This keeps discovery predictable without forcing false sameness where semantics differ.
+
+## Proposed Lyng modules
+
+### `lyng.io.http`
+
+Purpose:
+
+- high-level HTTP/HTTPS client backed by Ktor client
+
+Recommended declaration sketch:
+
+```lyng
+package lyng.io.http
+
+extern class HttpHeaders : Map<String, String> {
+    fun get(name: String): String?
+    fun getAll(name: String): List<String>
+    fun names(): List<String>
+}
+
+extern class HttpRequest {
+    var method: String
+    var url: String
+    var headers: Map<String, String>
+    var bodyText: String?
+    var bodyBytes: Buffer?
+    var timeoutMillis: Int?
+}
+
+extern class HttpResponse {
+    val status: Int
+    val statusText: String
+    val headers: HttpHeaders
+    fun text(): String
+    fun bytes(): Buffer
+}
+
+extern object Http {
+    fun isSupported(): Bool
+    fun request(req: HttpRequest): HttpResponse
+    fun get(url: String, headers...): HttpResponse
+    fun post(url: String, bodyText: String = "", contentType: String? = null, headers...): HttpResponse
+    fun postBytes(url: String, body: Buffer, contentType: String? = null, headers...): HttpResponse
+}
+```
+
+Notes:
+
+- `HttpRequest` is mutable because it is ergonomic in scripts.
+- `headers` is intentionally simple in v1: `Map<String, String>` for programmatic request construction.
+- `HttpHeaders` is primarily for response headers, where repeated names matter.
+- `text()` and `bytes()` should cache decoded content inside the response object.
+- For convenience methods, `headers...` should accept `MapEntry` values such as `"X-Token" => "abc"` and `[key, value]` pairs, then normalize them internally into request headers.
+
+### `lyng.io.ws`
+
+Purpose:
+
+- WebSocket client built on Ktor client WebSockets
+
+Recommended declaration sketch:
+
+```lyng
+package lyng.io.ws
+
+extern class WsMessage {
+    val isText: Bool
+    val text: String?
+    val data: Buffer?
+}
+
+extern class WsSession {
+    fun isOpen(): Bool
+    fun url(): String
+    fun sendText(text: String): void
+    fun sendBytes(data: Buffer): void
+    fun receive(): WsMessage?
+    fun close(code: Int = 1000, reason: String = ""): void
+}
+
+extern object Ws {
+    fun isSupported(): Bool
+    fun connect(url: String, headers...): WsSession
+}
+```
+
+Notes:
+
+- Keep frames hidden. Lyng sees messages.
+- `receive()` returns `null` on clean close.
+- v1 supports text and binary messages only.
+- `headers...` should follow the same rules as `Http.get(...)`: `MapEntry` values or `[key, value]` pairs.
+
+### `lyng.io.net`
+
+Purpose:
+
+- transport sockets backed by `ktor-network`
+
+Recommended declaration sketch:
+
+```lyng
+package lyng.io.net
+
+enum IpVersion {
+    IPV4,
+    IPV6
+}
+
+extern class SocketAddress {
+    val host: String
+    val port: Int
+    val ipVersion: IpVersion
+    val resolved: Bool
+    fun toString(): String
+}
+
+extern class Datagram {
+    val data: Buffer
+    val address: SocketAddress
+}
+
+extern class TcpSocket {
+    fun isOpen(): Bool
+    fun localAddress(): SocketAddress
+    fun remoteAddress(): SocketAddress
+    fun read(maxBytes: Int = 65536): Buffer?
+    fun readLine(): String?
+    fun write(data: Buffer): void
+    fun writeUtf8(text: String): void
+    fun flush(): void
+    fun close(): void
+}
+
+extern class TcpServer {
+    fun isOpen(): Bool
+    fun localAddress(): SocketAddress
+    fun accept(): TcpSocket
+    fun close(): void
+}
+
+extern class UdpSocket {
+    fun isOpen(): Bool
+    fun localAddress(): SocketAddress
+    fun receive(maxBytes: Int = 65536): Datagram?
+    fun send(data: Buffer, host: String, port: Int): void
+    fun close(): void
+}
+
+extern object Net {
+    fun isSupported(): Bool
+    fun isTcpAvailable(): Bool
+    fun isTcpServerAvailable(): Bool
+    fun isUdpAvailable(): Bool
+
+    fun resolve(host: String, port: Int): List<SocketAddress>
+
+    fun tcpConnect(
+        host: String,
+        port: Int,
+        timeoutMillis: Int? = null,
+        noDelay: Bool = true
+    ): TcpSocket
+
+    fun tcpListen(
+        port: Int,
+        host: String? = null,
+        backlog: Int = 128,
+        reuseAddress: Bool = true
+    ): TcpServer
+
+    fun udpBind(
+        port: Int = 0,
+        host: String? = null,
+        reuseAddress: Bool = true
+    ): UdpSocket
+}
+```
+
+Notes:
+
+- UDP is included in v1, but only with a minimal datagram API.
+- `udpBind` should bind an ephemeral port by default.
+- TCP server methods exist only where the backend supports them, but the declaration stays uniform.
+
+## Example usage
+
+HTTP:
+
+```lyng
+import lyng.io.http
+
+if (!Http.isSupported())
+    throw IllegalStateException("http is not supported here")
+
+val r = Http.get(
+    "https://example.com",
+    "Accept" => "text/plain",
+    "X-Trace" => "demo"
+)
+println(r.status)
+println(r.text())
+```
+
+WebSocket:
+
+```lyng
+import lyng.io.ws
+
+if (Ws.isSupported()) {
+    val ws = Ws.connect(
+        "wss://echo.example/ws",
+        "Authorization" => "Bearer <token>"
+    )
+    try {
+        ws.sendText("hello")
+        val msg = ws.receive()
+        if (msg != null && msg.isText)
+            println(msg.text)
+    } finally {
+        ws.close()
+    }
+}
+```
+
+TCP:
+
+```lyng
+import lyng.io.net
+
+if (Net.isTcpAvailable()) {
+    val s = Net.tcpConnect("example.com", 80)
+    try {
+        s.writeUtf8("GET / HTTP/1.1\r\nHost: example.com\r\nConnection: close\r\n\r\n")
+        s.flush()
+        while (true) {
+            val line = s.readLine()
+            if (line == null) break
+            println(line)
+        }
+    } finally {
+        s.close()
+    }
+}
+```
+
+TCP server:
+
+```lyng
+import lyng.io.net
+
+if (Net.isTcpServerAvailable()) {
+    val server = Net.tcpListen(4040, host="127.0.0.1")
+    println("listening on " + server.localAddress())
+
+    try {
+        while (server.isOpen()) {
+            val client = server.accept()
+            launch {
+                try {
+                    println("accepted " + client.remoteAddress())
+
+                    val requestLine = client.readLine()
+                    if (requestLine != null)
+                        println("request: " + requestLine)
+
+                    while (true) {
+                        val line = client.readLine()
+                        if (line == null || line == "") break
+                    }
+
+                    client.writeUtf8("hello from lyng server\n")
+                    client.flush()
+                } finally {
+                    client.close()
+                }
+            }
+        }
+    } finally {
+        server.close()
+    }
+}
+```
+
+UDP:
+
+```lyng
+import lyng.io.net
+
+if (Net.isUdpAvailable()) {
+    val udp = Net.udpBind()
+    try {
+        udp.send(Buffer("ping"), "127.0.0.1", 4041)
+        val d = udp.receive()
+        if (d != null)
+            println("from " + d.address + ": " + d.data)
+    } finally {
+        udp.close()
+    }
+}
+```
+
+## Platform support model
+
+The interface is uniform. Support is platform-dependent.
+
+Initial intent:
+
+| Platform | HTTP | WS client | TCP client | TCP server | UDP |
+| :--- | :---: | :---: | :---: | :---: | :---: |
+| JVM | yes | yes | yes | yes | yes |
+| Android | yes | yes | likely yes | likely yes | likely yes |
+| Native Linux/macOS | yes | yes | target | target | target |
+| Native Windows | yes | yes | target | target | target |
+| NodeJS | yes | engine-dependent | target | target | target |
+| Browser / Wasm | yes | engine-dependent | no or target-specific | no | no |
+
+Interpretation rules:
+
+- import succeeds when the module is installed
+- construction/operations may still fail if the specific feature is unavailable
+- discovery methods must let scripts avoid that path cleanly
+- `isSupported()` means the module has at least one useful implementation on the current runtime
+
+## Security model
+
+Use separate policies per module to avoid muddy authorization.
+
+Recommended policies:
+
+- `HttpAccessPolicy`
+- `WsAccessPolicy`
+- `NetAccessPolicy`
+
+Suggested operations:
+
+```kotlin
+sealed interface HttpAccessOp {
+    data class Request(val method: String, val url: String) : HttpAccessOp
+}
+
+sealed interface WsAccessOp {
+    data class Connect(val url: String) : WsAccessOp
+    data class Send(val url: String, val bytes: Int, val isText: Boolean) : WsAccessOp
+    data class Receive(val url: String) : WsAccessOp
+}
+
+sealed interface NetAccessOp {
+    data class Resolve(val host: String, val port: Int) : NetAccessOp
+    data class TcpConnect(val host: String, val port: Int) : NetAccessOp
+    data class TcpListen(val host: String?, val port: Int, val backlog: Int) : NetAccessOp
+    data class TcpAccept(val localHost: String?, val localPort: Int, val remoteHost: String, val remotePort: Int) : NetAccessOp
+    data class TcpRead(val remoteHost: String, val remotePort: Int, val requestedBytes: Int) : NetAccessOp
+    data class TcpWrite(val remoteHost: String, val remotePort: Int, val bytes: Int) : NetAccessOp
+    data class UdpBind(val host: String?, val port: Int) : NetAccessOp
+    data class UdpSend(val host: String, val port: Int, val bytes: Int) : NetAccessOp
+    data class UdpReceive(val localHost: String?, val localPort: Int, val requestedBytes: Int) : NetAccessOp
+}
+```
+
+This is intentionally strict. It lets embedders enforce:
+
+- allow HTTP but forbid raw sockets
+- allow outbound TCP but forbid listening sockets
+- allow UDP only on loopback
+- allow WebSockets only to whitelisted hosts
+
+## Error mapping
+
+Like other `lyngio` modules, host exceptions should be mapped into Lyng runtime errors.
+
+Recommended v1 mapping:
+
+- policy denial -> illegal operation
+- malformed URL / invalid host / invalid port -> illegal argument
+- connect failure / bind failure / timeout / protocol failure -> illegal state
+
+Later, if needed, add typed Lyng exceptions such as:
+
+- `HttpException`
+- `WebSocketException`
+- `NetworkException`
+- `TimeoutException`
+
+## Implementation outline
+
+Recommended layout:
+
+- `lyngio/stdlib/lyng/io/http.lyng`
+- `lyngio/stdlib/lyng/io/ws.lyng`
+- `lyngio/stdlib/lyng/io/net.lyng`
+- `lyngio/src/commonMain/kotlin/net/sergeych/lyng/io/http/LyngHttpModule.kt`
+- `lyngio/src/commonMain/kotlin/net/sergeych/lyng/io/ws/LyngWsModule.kt`
+- `lyngio/src/commonMain/kotlin/net/sergeych/lyng/io/net/LyngNetModule.kt`
+- `lyngio/src/commonMain/kotlin/net/sergeych/lyngio/http/...`
+- `lyngio/src/commonMain/kotlin/net/sergeych/lyngio/ws/...`
+- `lyngio/src/commonMain/kotlin/net/sergeych/lyngio/net/...`
+
+Module installers should mirror existing `lyngio` patterns:
+
+```kotlin
+fun createHttpModule(policy: HttpAccessPolicy, scope: Scope): Boolean
+fun createWsModule(policy: WsAccessPolicy, scope: Scope): Boolean
+fun createNetModule(policy: NetAccessPolicy, scope: Scope): Boolean
+```
+
+As with `lyng.io.console`, the registrar should evaluate embedded `.lyng` declarations into module scope.
+
+## Why this is better than the earlier raw-sockets-first plan
+
+- it delivers useful networking sooner
+- it covers HTTP and WebSocket immediately, not as future work
+- it reuses mature KMP networking code instead of creating a transport stack from scratch
+- it still leaves room for a later low-level socket API if Ktor abstractions prove insufficient
+
+## Open questions
+
+1. Should `Http` use static convenience methods only in v1, or also expose a reusable `HttpClient`-like Lyng object later?
+2. Should `Ws.connect(...)` accept only URL plus headers, or also subprotocols in v1?
+3. Should `TcpSocket.readExact(...)` be included from the start, or wait until there is a real use case?
+4. Should `UdpSocket.send(...)` accept `SocketAddress` overloads in v1, or only `host` and `port`?
+5. Should `isSupported()` return true when only a subset of the module works, or should module support be stricter?
+
+## Recommended implementation order
+
+1. `lyng.io.http`
+2. `lyng.io.ws`
+3. `lyng.io.net` TCP client
+4. `lyng.io.net` TCP server
+5. `lyng.io.net` UDP
+
+This order matches both practical usefulness and implementation risk.

site/src/jsMain/resources/index.html

@@ -413,6 +413,9 @@
                         </li>
                     </ul>
                 </li>
+                <li class="nav-item">
+                    <a class="nav-link" href="#/docs/downloads.md" data-route="downloads">Downloads</a>
+                </li>
                 <li class="nav-item">
                     <a class="nav-link" href="#/tryling" data-route="tryling">Try in browser</a>
                 </li>
@@ -492,6 +495,8 @@
             var activeLink = null;
             if (!hash || hash === '#' || hash === '#/') {
                 activeLink = document.querySelector('#topbarNav .nav-link[data-route="home"]');
+            } else if (hash.startsWith('#/docs/downloads.md')) {
+                activeLink = document.querySelector('#topbarNav .nav-link[data-route="downloads"]');
             } else if (hash.startsWith('#/docs/') || hash.startsWith('#/authors')) {
                 // Mark Docs menu root as active
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