diff --git a/lyng/src/jvmTest/kotlin/net/sergeych/CliLocalModuleImportRegressionJvmTest.kt b/lyng/src/jvmTest/kotlin/net/sergeych/CliLocalModuleImportRegressionJvmTest.kt
index 831c13a..1f54e34 100644
--- a/lyng/src/jvmTest/kotlin/net/sergeych/CliLocalModuleImportRegressionJvmTest.kt
+++ b/lyng/src/jvmTest/kotlin/net/sergeych/CliLocalModuleImportRegressionJvmTest.kt
@@ -1,40 +1,92 @@
 package net.sergeych
 
+import net.sergeych.lyng.EvalSession
+import net.sergeych.lyng.Source
+import net.sergeych.lyng.obj.ObjString
 import kotlinx.coroutines.runBlocking
 import java.nio.file.Files
 import kotlin.io.path.writeText
 import kotlin.test.Test
+import kotlin.test.assertEquals
 
 class CliLocalModuleImportRegressionJvmTest {
 
+    private fun writeTransitiveImportTree(root: java.nio.file.Path) {
+        val packageDir = Files.createDirectories(root.resolve("package1"))
+        val nestedDir = Files.createDirectories(packageDir.resolve("nested"))
+
+        packageDir.resolve("alpha.lyng").writeText(
+            """
+            package package1.alpha
+
+            import lyng.stdlib
+            import lyng.io.net
+
+            class Alpha {
+                val headers = Map<String, String>()
+
+                fun makeTask(port: Int, host: String): Deferred = launch {
+                    host + ":" + port
+                }
+
+                fun netModule() = Net
+            }
+
+            fun alphaValue() = "alpha"
+            """.trimIndent()
+        )
+        packageDir.resolve("beta.lyng").writeText(
+            """
+            package package1.beta
+
+            import lyng.stdlib
+            import package1.alpha
+
+            fun betaValue() = alphaValue() + "|beta"
+            """.trimIndent()
+        )
+        nestedDir.resolve("gamma.lyng").writeText(
+            """
+            package package1.nested.gamma
+
+            import lyng.io.net
+            import package1.alpha
+            import package1.beta
+
+            val String.gammaTag get() = this + "|gamma"
+
+            fun gammaValue() = betaValue().gammaTag
+            fun netModule() = Net
+            """.trimIndent()
+        )
+        packageDir.resolve("entry.lyng").writeText(
+            """
+            package package1.entry
+
+            import lyng.stdlib
+            import lyng.io.net
+            import package1.alpha
+            import package1.beta
+            import package1.nested.gamma
+
+            fun report() = gammaValue() + "|entry"
+            """.trimIndent()
+        )
+    }
+
     @Test
     fun localModuleUsingLaunchAndNetImportsWithoutStdlibRedefinition() = runBlocking {
         val root = Files.createTempDirectory("lyng-cli-import-regression")
         try {
-            val packageDir = Files.createDirectories(root.resolve("package1"))
             val mainFile = root.resolve("main.lyng")
-            val alphaFile = packageDir.resolve("alpha.lyng")
-
+            writeTransitiveImportTree(root)
             mainFile.writeText(
                 """
-                import package1.alpha
+                import package1.entry
+                import package1.beta
+                import package1.nested.gamma
 
-                println("ok")
-                """.trimIndent()
-            )
-            alphaFile.writeText(
-                """
-                import lyng.io.net
-
-                class Alpha {
-                    val headers = Map<String, String>()
-
-                    fn startListen(port, host) {
-                        launch {
-                            println(port, host)
-                        }
-                    }
-                }
+                println(report())
                 """.trimIndent()
             )
 
@@ -43,4 +95,43 @@ class CliLocalModuleImportRegressionJvmTest {
             root.toFile().deleteRecursively()
         }
     }
+
+    @Test
+    fun localModuleImportsAreNoOpsWhenEvaldRepeatedlyOnSameCliContext() = runBlocking {
+        val root = Files.createTempDirectory("lyng-cli-import-regression-repeat")
+        try {
+            val mainFile = root.resolve("main.lyng")
+            writeTransitiveImportTree(root)
+            mainFile.writeText("println(\"bootstrap\")")
+
+            val session = EvalSession(newCliScope(emptyList(), mainFile.toString()))
+            try {
+                repeat(5) { index ->
+                    val result = evalOnCliDispatcher(
+                        session,
+                        Source(
+                            "<repeat-local-import-$index>",
+                            """
+                            import package1.entry
+                            import package1.nested.gamma
+                            import package1.beta
+                            import package1.alpha
+
+                            report()
+                            """.trimIndent()
+                        )
+                    ) as ObjString
+
+                    assertEquals(
+                        "alpha|beta|gamma|entry",
+                        result.value
+                    )
+                }
+            } finally {
+                session.cancelAndJoin()
+            }
+        } finally {
+            root.toFile().deleteRecursively()
+        }
+    }
 }
diff --git a/lyng/src/jvmTest/kotlin/net/sergeych/lyng_cli/CliLocalImportsJvmTest.kt b/lyng/src/jvmTest/kotlin/net/sergeych/lyng_cli/CliLocalImportsJvmTest.kt
index 6f37af6..77afd02 100644
--- a/lyng/src/jvmTest/kotlin/net/sergeych/lyng_cli/CliLocalImportsJvmTest.kt
+++ b/lyng/src/jvmTest/kotlin/net/sergeych/lyng_cli/CliLocalImportsJvmTest.kt
@@ -64,6 +64,73 @@ class CliLocalImportsJvmTest {
         return CliResult(outBuf.toString("UTF-8"), errBuf.toString("UTF-8"), exitCode)
     }
 
+    private fun writeTransitiveImportTree(root: java.nio.file.Path) {
+        val packageDir = Files.createDirectories(root.resolve("package1"))
+        val nestedDir = Files.createDirectories(packageDir.resolve("nested"))
+
+        Files.writeString(
+            packageDir.resolve("alpha.lyng"),
+            """
+            package package1.alpha
+
+            import lyng.stdlib
+            import lyng.io.net
+
+            class Alpha {
+                val headers = Map<String, String>()
+
+                fun makeTask(port: Int, host: String): Deferred = launch {
+                    host + ":" + port
+                }
+
+                fun netModule() = Net
+            }
+
+            fun alphaValue() = "alpha"
+            """.trimIndent()
+        )
+        Files.writeString(
+            packageDir.resolve("beta.lyng"),
+            """
+            package package1.beta
+
+            import lyng.stdlib
+            import package1.alpha
+
+            fun betaValue() = alphaValue() + "|beta"
+            """.trimIndent()
+        )
+        Files.writeString(
+            nestedDir.resolve("gamma.lyng"),
+            """
+            package package1.nested.gamma
+
+            import lyng.io.net
+            import package1.alpha
+            import package1.beta
+
+            val String.gammaTag get() = this + "|gamma"
+
+            fun gammaValue() = betaValue().gammaTag
+            fun netModule() = Net
+            """.trimIndent()
+        )
+        Files.writeString(
+            packageDir.resolve("entry.lyng"),
+            """
+            package package1.entry
+
+            import lyng.stdlib
+            import lyng.io.net
+            import package1.alpha
+            import package1.beta
+            import package1.nested.gamma
+
+            fun report() = gammaValue() + "|entry"
+            """.trimIndent()
+        )
+    }
+
     @Test
     fun cliDiscoversSiblingAndNestedLocalImportsFromEntryRoot() {
         val dir = Files.createTempDirectory("lyng_cli_local_imports_")
@@ -134,4 +201,37 @@ class CliLocalImportsJvmTest {
             dir.toFile().deleteRecursively()
         }
     }
+
+    @Test
+    fun cliHandlesOverlappingDirectoryImportsWithTransitiveStdlibAndNetSymbols() {
+        val dir = Files.createTempDirectory("lyng_cli_local_imports_transitive_")
+        try {
+            val mainFile = dir.resolve("main.lyng")
+            writeTransitiveImportTree(dir)
+            Files.writeString(
+                mainFile,
+                """
+                import package1.entry
+                import package1.beta
+                import package1.nested.gamma
+
+                println(report())
+                println(gammaValue())
+                """.trimIndent()
+            )
+
+            val result = runCli(mainFile.toString())
+            assertTrue(result.err, result.err.isBlank())
+            assertTrue(
+                result.out,
+                result.out.contains("alpha|beta|gamma|entry")
+            )
+            assertTrue(
+                result.out,
+                result.out.contains("alpha|beta|gamma")
+            )
+        } finally {
+            dir.toFile().deleteRecursively()
+        }
+    }
 }
diff --git a/lynglib/src/commonTest/kotlin/ScriptImportPreparationTest.kt b/lynglib/src/commonTest/kotlin/ScriptImportPreparationTest.kt
index 6a82ff2..2444b1a 100644
--- a/lynglib/src/commonTest/kotlin/ScriptImportPreparationTest.kt
+++ b/lynglib/src/commonTest/kotlin/ScriptImportPreparationTest.kt
@@ -16,17 +16,60 @@
 
 import kotlinx.coroutines.test.runTest
 import net.sergeych.lyng.Compiler
+import net.sergeych.lyng.EvalSession
 import net.sergeych.lyng.Script
 import net.sergeych.lyng.Source
+import net.sergeych.lyng.obj.ObjString
 import net.sergeych.lyng.obj.toInt
 import net.sergeych.lyng.pacman.ImportManager
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertNotNull
 import kotlin.test.assertNull
+import kotlin.test.assertSame
 
 class ScriptImportPreparationTest {
 
+    private fun nestedImportSources(prefix: String): Array<String> =
+        arrayOf(
+            """
+            package $prefix.alpha
+
+            class Alpha {
+                val headers = Map<String, String>()
+
+                fun tagged(port: Int, host: String): String {
+                    val task: Deferred = launch {
+                        host + ":" + port + ":" + headers.size
+                    }
+                    return task.await()
+                }
+            }
+
+            fun alphaValue() = Alpha().tagged(7, "alpha")
+            """.trimIndent(),
+            """
+            package $prefix.beta
+            import $prefix.alpha
+
+            fun betaValue() = alphaValue() + "|" + Alpha().tagged(8, "beta")
+            """.trimIndent(),
+            """
+            package $prefix.gamma
+            import $prefix.alpha
+            import $prefix.beta
+
+            val String.gammaTag get() = this + ":gamma"
+
+            fun gammaValue() = betaValue() + "|" + "done".gammaTag
+            """.trimIndent()
+        )
+
+    private fun nestedImportManager(prefix: String = "tree"): ImportManager =
+        Script.defaultImportManager.copy().apply {
+            addTextPackages(*nestedImportSources(prefix))
+        }
+
     @Test
     fun scriptImportIntoExplicitlyPreparesExistingScope() = runTest {
         val manager = ImportManager()
@@ -84,4 +127,67 @@ class ScriptImportPreparationTest {
         val record = assertNotNull(module["answer"])
         assertEquals(42, module.resolve(record, "answer").toInt())
     }
+
+    @Test
+    fun repeatedImportIntoOnSameScopeIsIdempotentForNestedPackageGraph() = runTest {
+        val manager = nestedImportManager()
+        val script = Compiler.compile(
+            Source(
+                "<repeat-import-into>",
+                """
+                import tree.gamma
+                import tree.beta
+                import tree.alpha
+
+                gammaValue()
+                """.trimIndent()
+            ),
+            manager
+        )
+        val scope = manager.newStdScope()
+
+        script.importInto(scope)
+        val importedGammaValue = assertNotNull(scope["gammaValue"])
+        val importedAlpha = assertNotNull(scope["Alpha"])
+
+        repeat(5) {
+            script.importInto(scope)
+        }
+
+        assertSame(importedGammaValue, scope["gammaValue"])
+        assertSame(importedAlpha, scope["Alpha"])
+        assertEquals(
+            "alpha:7:0|beta:8:0|done:gamma",
+            (script.execute(scope) as ObjString).value
+        )
+    }
+
+    @Test
+    fun repeatedEvalOnSameSessionCanReimportNestedPackageGraph() = runTest {
+        val prefix = "repeattree"
+        val manager = nestedImportManager(prefix)
+        val scope = manager.newModule()
+        val session = EvalSession(scope)
+
+        try {
+            repeat(5) { index ->
+                val result = session.eval(
+                    Source(
+                        "<repeat-eval-$index>",
+                        """
+                        import $prefix.gamma
+                        import $prefix.beta
+                        import $prefix.alpha
+
+                        gammaValue()
+                        """.trimIndent()
+                    )
+                ) as ObjString
+
+                assertEquals("alpha:7:0|beta:8:0|done:gamma", result.value)
+            }
+        } finally {
+            session.cancelAndJoin()
+        }
+    }
 }