diff --git a/packages/codemode/AGENTS.md b/packages/codemode/AGENTS.md
index 47228beb77c..66f962e081e 100644
--- a/packages/codemode/AGENTS.md
+++ b/packages/codemode/AGENTS.md
@@ -1,5 +1,6 @@
 # @opencode/codemode
 
 - `interpreter-support.md` is a checklist, not a changelog: check off newly added support and add unchecked items for significant gaps. Leave it alone for fixes and refactors.
-- Program values are `Value` (`src/vm/runtime/objects.ts`). Host values are `unknown` and enter only through `fromHost` and `fromJson`; do not widen program-facing signatures to `unknown`.
+- Program values are `Value` (`src/runtime/objects.ts`). Host values are `unknown` and enter only through `fromHost` and `fromJson`; do not widen program-facing signatures to `unknown`.
 - Each built-in object kind is one `Obj` subclass (`Wrapper` or `Opaque`) that overrides the hooks it needs. Ask the object instead of adding `instanceof` ladders.
+- The core VM, compiler, prelude, snapshot, and stdlib modules must not import `effect`; Effect lives only in the host boundary and driver (`src/runtime/`, `src/openapi/`, and the top-level tool/runtime entrypoints).
diff --git a/packages/codemode/README.md b/packages/codemode/README.md
index 8b429a54edf..f5a2730f67f 100644
--- a/packages/codemode/README.md
+++ b/packages/codemode/README.md
@@ -246,7 +246,7 @@ Every value crossing in either direction is converted, never shared: arguments c
 copies, and a function inside a result is callable the same way. A global that shadows a built-in or another
 extension throws at `CodeMode.make`.
 
-Functions inside a result have no data form, so a suspended VM run loses them by default: after a resume, calling one
+Functions inside a result have no data form, so a suspended run loses them by default: after a resume, calling one
 throws a `TypeError`. An extension can preserve them across suspend and resume with `snapshot` hooks. `encode` receives
 a value one of the extension's functions returned, as the host function returned it, and returns plain data (JSON
 values and `Uint8Array`s); on resume, `decode` receives that data once per value and returns a host value of the same
diff --git a/packages/codemode/script/bench.ts b/packages/codemode/script/bench.ts
index 1940316ee73..0d9027846b6 100644
--- a/packages/codemode/script/bench.ts
+++ b/packages/codemode/script/bench.ts
@@ -6,7 +6,7 @@
 import { numberOfDFGCompiles, reoptimizationRetryCount } from "bun:jsc"
 import { Effect, Schema } from "effect"
 import { CodeMode, Tool } from "../src/index.js"
-import { Vm } from "../src/vm/vm.js"
+import { Vm } from "../src/vm.js"
 
 const cases: ReadonlyArray<readonly [name: string, code: string]> = [
   [
diff --git a/packages/codemode/script/disasm.ts b/packages/codemode/script/disasm.ts
index 1d031790042..d3e114270ff 100644
--- a/packages/codemode/script/disasm.ts
+++ b/packages/codemode/script/disasm.ts
@@ -1,9 +1,9 @@
 #!/usr/bin/env bun
 
 // The bytecode disassembler: pcs, ops, constants, handler and finally tables, local names, source lines.
-import { sourceLocation } from "../src/vm/runtime/model.js"
-import type { Code } from "../src/vm/code.js"
-import { compileSource } from "../src/vm/compiler/compile.js"
+import { sourceLocation } from "../src/runtime/model.js"
+import type { Code } from "../src/code.js"
+import { compileSource } from "../src/compiler/compile.js"
 import {
   BinOpSymbols,
   CheckBaseKind,
@@ -13,8 +13,8 @@ import {
   OpNames,
   PutKind,
   UnaryOpSymbols,
-} from "../src/vm/opcodes.js"
-import { parseProgram } from "../src/vm/runtime/execute.js"
+} from "../src/opcodes.js"
+import { parseProgram } from "../src/runtime/execute.js"
 
 const formatFlags = (flags: number): string => {
   const names: Array<string> = []
diff --git a/packages/codemode/script/prelude.ts b/packages/codemode/script/prelude.ts
index ca4c5c92587..b57e1ff0783 100644
--- a/packages/codemode/script/prelude.ts
+++ b/packages/codemode/script/prelude.ts
@@ -1,15 +1,15 @@
 #!/usr/bin/env bun
 
-// Compiles the built-in sources (the prelude, the VM's internal helpers) ahead of time into src/vm/prelude/bytecode.json,
-// which a process loads instead of parsing and compiling them (see src/vm/prelude/bytecode.ts). Run it after changing
-// either source or the compiler; test/vm/prelude-bytecode.test.ts fails until then.
+// Compiles the built-in sources (the prelude, the VM's internal helpers) ahead of time into src/prelude/bytecode.json,
+// which a process loads instead of parsing and compiling them (see src/prelude/bytecode.ts). Run it after changing
+// either source or the compiler; test/prelude-bytecode.test.ts fails until then.
 
 import { parse } from "acorn"
-import { Source } from "../src/vm/runtime/source.js"
-import { saveCodes } from "../src/vm/prelude/bytecode.js"
-import { code } from "../src/vm/prelude/source.js"
-import { compileSource } from "../src/vm/compiler/compile.js"
-import { INTERNAL_SOURCE } from "../src/vm/internal-prelude.js"
+import { Source } from "../src/runtime/source.js"
+import { saveCodes } from "../src/prelude/bytecode.js"
+import { code } from "../src/prelude/source.js"
+import { compileSource } from "../src/compiler/compile.js"
+import { INTERNAL_SOURCE } from "../src/internal-prelude.js"
 
 export const compileBuiltins = () =>
   Object.fromEntries(
@@ -23,5 +23,5 @@ export const compileBuiltins = () =>
   )
 
 if (import.meta.main) {
-  await Bun.write(new URL("../src/vm/prelude/bytecode.json", import.meta.url), `${JSON.stringify(compileBuiltins())}\n`)
+  await Bun.write(new URL("../src/prelude/bytecode.json", import.meta.url), `${JSON.stringify(compileBuiltins())}\n`)
 }
diff --git a/packages/codemode/script/setup.ts b/packages/codemode/script/setup.ts
index 03459c5140a..49603b79586 100644
--- a/packages/codemode/script/setup.ts
+++ b/packages/codemode/script/setup.ts
@@ -5,8 +5,8 @@
 
 import { Effect } from "effect"
 import { CodeMode } from "../src/index.js"
-import { Interpreter } from "../src/vm/runtime/interpreter.js"
-import { createBuiltins } from "../src/vm/runtime/intrinsics.js"
+import { Interpreter } from "../src/runtime/interpreter.js"
+import { createBuiltins } from "../src/runtime/intrinsics.js"
 import { ToolRuntime } from "../src/tool-runtime.js"
 
 const index = process.argv.indexOf("--iterations")
diff --git a/packages/codemode/src/vm/async.ts b/packages/codemode/src/async.ts
similarity index 99%
rename from packages/codemode/src/vm/async.ts
rename to packages/codemode/src/async.ts
index 9a323ee02f4..3eae192d5be 100644
--- a/packages/codemode/src/vm/async.ts
+++ b/packages/codemode/src/async.ts
@@ -1,4 +1,4 @@
-import type { Diagnostic } from "../codemode.js"
+import type { Diagnostic } from "./codemode.js"
 import { normalizeError, locate } from "./runtime/errors.js"
 import { MAX_PENDING_PROMISES } from "./runtime/limits.js"
 import { type AstNode, IteratorSymbol, rangeError, typeError } from "./runtime/model.js"
diff --git a/packages/codemode/src/vm/code.ts b/packages/codemode/src/code.ts
similarity index 100%
rename from packages/codemode/src/vm/code.ts
rename to packages/codemode/src/code.ts
diff --git a/packages/codemode/src/codemode.ts b/packages/codemode/src/codemode.ts
index 219808df170..3e64f89b2fc 100644
--- a/packages/codemode/src/codemode.ts
+++ b/packages/codemode/src/codemode.ts
@@ -3,11 +3,11 @@ import type { Extension } from "./extension.js"
 import { scanTools } from "./scan.js"
 import { type Services, type ToolDescription, ToolRuntime } from "./tool-runtime.js"
 import type { Tools } from "./tools.js"
-import { fromJson } from "./vm/data.js"
-import { finishExecution, resumeProgram, type Running, type Setup, startProgram, SuspendError } from "./vm/runtime/execute.js"
-import { extensionGlobals } from "./vm/runtime/extensions.js"
-import { globalNames } from "./vm/runtime/globals.js"
-import { fromBytes, type Snapshot, SnapshotError, type SnapshotHeader, toBytes } from "./vm/snapshot/snapshot.js"
+import { fromJson } from "./data.js"
+import { finishExecution, resumeProgram, type Running, type Setup, startProgram, SuspendError } from "./runtime/execute.js"
+import { extensionGlobals } from "./runtime/extensions.js"
+import { globalNames } from "./runtime/globals.js"
+import { fromBytes, type Snapshot, SnapshotError, type SnapshotHeader, toBytes } from "./snapshot/snapshot.js"
 
 export { fromBytes, scanTools, SnapshotError, SuspendError, toBytes }
 export type { Snapshot, SnapshotHeader }
@@ -173,7 +173,7 @@ export type Runtime<R = never> = {
 }
 
 /**
- * One run of a program on the VM. `run()` runs it in the current fiber until it ends or is suspended, and owns its host
+ * One run of a program. `run()` runs it in the current fiber until it ends or is suspended, and owns its host
  * calls: interrupting `run()` interrupts them. A program runs once: running it again is a defect.
  */
 export type Program<R = never, E = never> = {
diff --git a/packages/codemode/src/vm/compiler/compile.ts b/packages/codemode/src/compiler/compile.ts
similarity index 100%
rename from packages/codemode/src/vm/compiler/compile.ts
rename to packages/codemode/src/compiler/compile.ts
diff --git a/packages/codemode/src/vm/compiler/scope.ts b/packages/codemode/src/compiler/scope.ts
similarity index 100%
rename from packages/codemode/src/vm/compiler/scope.ts
rename to packages/codemode/src/compiler/scope.ts
diff --git a/packages/codemode/src/vm/data.ts b/packages/codemode/src/data.ts
similarity index 95%
rename from packages/codemode/src/vm/data.ts
rename to packages/codemode/src/data.ts
index 8fabac36cc6..8a3dd2f1d32 100644
--- a/packages/codemode/src/vm/data.ts
+++ b/packages/codemode/src/data.ts
@@ -1,5 +1,3 @@
-export * as Data from "./data.js"
-
 import type { Json } from "./snapshot/codec.js"
 import type { Interpreter } from "./runtime/interpreter.js"
 import { Arr, define, Obj, type Value } from "./runtime/objects.js"
diff --git a/packages/codemode/src/extension.ts b/packages/codemode/src/extension.ts
index 3c65a77afce..8ca6b9b8332 100644
--- a/packages/codemode/src/extension.ts
+++ b/packages/codemode/src/extension.ts
@@ -13,7 +13,7 @@ import type { Effect } from "effect"
  * promise of an asynchronous global and by throwing from a synchronous one. Functions inside a global object are
  * called the same way, named by their path (`fs.readFile`).
  *
- * Programs can also `import` or `require` a global by its Node module name; see `interpreter/modules.ts`.
+ * Programs can also `import` or `require` a global by its Node module name; see `runtime/modules.ts`.
  */
 export type Extension<Globals extends Readonly<Record<string, unknown>> = Readonly<Record<string, unknown>>> = {
   readonly name: string
diff --git a/packages/codemode/src/vm/generators.ts b/packages/codemode/src/generators.ts
similarity index 100%
rename from packages/codemode/src/vm/generators.ts
rename to packages/codemode/src/generators.ts
diff --git a/packages/codemode/src/vm/host.ts b/packages/codemode/src/host.ts
similarity index 99%
rename from packages/codemode/src/vm/host.ts
rename to packages/codemode/src/host.ts
index 67b4fe737d7..d1fdc3fd594 100644
--- a/packages/codemode/src/vm/host.ts
+++ b/packages/codemode/src/host.ts
@@ -1,4 +1,4 @@
-import type { Diagnostic } from "../codemode.js"
+import type { Diagnostic } from "./codemode.js"
 import { fromJson, type Json } from "./data.js"
 import { startExtensionCall } from "./runtime/extensions.js"
 import type { Interpreter } from "./runtime/interpreter.js"
@@ -7,7 +7,7 @@ import { Arr, PromiseObj, type Value } from "./runtime/objects.js"
 import { promiseLike } from "./runtime/promises.js"
 import type { Completion } from "./runtime/signals.js"
 import { type ExtensionRequest, HostCall, type HostRequest, Resolving } from "./scheduler.js"
-import type { ExtensionInvocation } from "../tool-runtime.js"
+import type { ExtensionInvocation } from "./tool-runtime.js"
 import type { Code } from "./code.js"
 import { internalCode, tryFastBoundaryOrJson, VmIntrinsic } from "./internal-prelude.js"
 import { type FrameMode, Mode, type Vm } from "./vm.js"
diff --git a/packages/codemode/src/vm/internal-prelude.ts b/packages/codemode/src/internal-prelude.ts
similarity index 100%
rename from packages/codemode/src/vm/internal-prelude.ts
rename to packages/codemode/src/internal-prelude.ts
diff --git a/packages/codemode/src/vm/opcodes.ts b/packages/codemode/src/opcodes.ts
similarity index 99%
rename from packages/codemode/src/vm/opcodes.ts
rename to packages/codemode/src/opcodes.ts
index 0f84a541fe9..d81ef7a6f9f 100644
--- a/packages/codemode/src/vm/opcodes.ts
+++ b/packages/codemode/src/opcodes.ts
@@ -1,4 +1,4 @@
-import type { DiagnosticKind } from "../codemode.js"
+import type { DiagnosticKind } from "./codemode.js"
 import type { ErrorType } from "./runtime/intrinsics.js"
 
 /** Uninitialized lexical binding sentinel (temporal dead zone). */
diff --git a/packages/codemode/src/vm/prelude/bytecode.json b/packages/codemode/src/prelude/bytecode.json
similarity index 100%
rename from packages/codemode/src/vm/prelude/bytecode.json
rename to packages/codemode/src/prelude/bytecode.json
diff --git a/packages/codemode/src/vm/prelude/bytecode.ts b/packages/codemode/src/prelude/bytecode.ts
similarity index 100%
rename from packages/codemode/src/vm/prelude/bytecode.ts
rename to packages/codemode/src/prelude/bytecode.ts
diff --git a/packages/codemode/src/vm/prelude/helpers.ts b/packages/codemode/src/prelude/helpers.ts
similarity index 99%
rename from packages/codemode/src/vm/prelude/helpers.ts
rename to packages/codemode/src/prelude/helpers.ts
index f213fade8a9..1d02f065d84 100644
--- a/packages/codemode/src/vm/prelude/helpers.ts
+++ b/packages/codemode/src/prelude/helpers.ts
@@ -33,7 +33,7 @@ import {
 } from "../runtime/objects.js"
 import { builtinCursor, requireIteratorObject } from "../runtime/operations.js"
 import { containsOpaqueReference, describeValue, isOpaque } from "../runtime/references.js"
-import { compareText } from "../../tool-runtime.js"
+import { compareText } from "../tool-runtime.js"
 import { Invoke } from "../runtime/signals.js"
 
 // The prelude's privileged helpers: leaf built-ins (they never call program code) bound only in the prelude's scope.
diff --git a/packages/codemode/src/vm/prelude/prelude.ts b/packages/codemode/src/prelude/prelude.ts
similarity index 100%
rename from packages/codemode/src/vm/prelude/prelude.ts
rename to packages/codemode/src/prelude/prelude.ts
diff --git a/packages/codemode/src/vm/prelude/source.ts b/packages/codemode/src/prelude/source.ts
similarity index 100%
rename from packages/codemode/src/vm/prelude/source.ts
rename to packages/codemode/src/prelude/source.ts
diff --git a/packages/codemode/src/vm/runtime/callback.ts b/packages/codemode/src/runtime/callback.ts
similarity index 100%
rename from packages/codemode/src/vm/runtime/callback.ts
rename to packages/codemode/src/runtime/callback.ts
diff --git a/packages/codemode/src/vm/runtime/driver.ts b/packages/codemode/src/runtime/driver.ts
similarity index 99%
rename from packages/codemode/src/vm/runtime/driver.ts
rename to packages/codemode/src/runtime/driver.ts
index f5e77e0e2d5..e9039c1d43f 100644
--- a/packages/codemode/src/vm/runtime/driver.ts
+++ b/packages/codemode/src/runtime/driver.ts
@@ -1,7 +1,7 @@
 import { Cause, type Context, Effect, Exit, Fiber } from "effect"
 import type { Json } from "../data.js"
 import type { HostCall } from "../scheduler.js"
-import { type ToolRuntime, toolExpression } from "../../tool-runtime.js"
+import { type ToolRuntime, toolExpression } from "../tool-runtime.js"
 import { locate } from "./errors.js"
 import { PendingThrow } from "./model.js"
 import type { Vm } from "../vm.js"
diff --git a/packages/codemode/src/vm/runtime/errors.ts b/packages/codemode/src/runtime/errors.ts
similarity index 97%
rename from packages/codemode/src/vm/runtime/errors.ts
rename to packages/codemode/src/runtime/errors.ts
index 83748ec9a1b..4e9ce352fc2 100644
--- a/packages/codemode/src/vm/runtime/errors.ts
+++ b/packages/codemode/src/runtime/errors.ts
@@ -1,6 +1,6 @@
-import type { Diagnostic } from "../../codemode.js"
-import { ToolError } from "../../tool-error.js"
-import { ToolRuntimeError } from "../../tool-runtime.js"
+import type { Diagnostic } from "../codemode.js"
+import { ToolError } from "../tool-error.js"
+import { ToolRuntimeError } from "../tool-runtime.js"
 import { type AstNode, formatLocation, PendingThrow, Throw, sourceLocation } from "./model.js"
 import { containsRuntimeReference } from "./references.js"
 import { createErrorValue, type ErrorType, isErrorType } from "./intrinsics.js"
diff --git a/packages/codemode/src/vm/runtime/execute.ts b/packages/codemode/src/runtime/execute.ts
similarity index 97%
rename from packages/codemode/src/vm/runtime/execute.ts
rename to packages/codemode/src/runtime/execute.ts
index f4e5c1c9af8..20bb53d9262 100644
--- a/packages/codemode/src/vm/runtime/execute.ts
+++ b/packages/codemode/src/runtime/execute.ts
@@ -1,8 +1,8 @@
 import { parse, type Program } from "acorn"
 import { Cause, Deferred, Effect, Option, Schema } from "effect"
-import type { DataValue, Diagnostic, Outcome, ResolvedExecutionLimits, Result, Suspended } from "../../codemode.js"
+import type { DataValue, Diagnostic, Outcome, ResolvedExecutionLimits, Result, Suspended } from "../codemode.js"
 import { fromBytes, header, type Snapshot, SnapshotError, toBytes } from "../snapshot/snapshot.js"
-import { ToolRuntime } from "../../tool-runtime.js"
+import { ToolRuntime } from "../tool-runtime.js"
 import { normalizeError } from "./errors.js"
 import { createBuiltins } from "./intrinsics.js"
 import { Interpreter } from "./interpreter.js"
@@ -47,17 +47,6 @@ export const finishExecution = <E, R>(outcome: Effect.Effect<Outcome, E, R>): Ef
     }
   })
 
-export const executeProgram = <R>(
-  code: string,
-  prepared: ToolRuntime.Prepared<R>,
-  limits: ResolvedExecutionLimits,
-  hooks: ToolRuntime.Hooks<R>,
-  globals?: Globals<R>,
-  bindings?: Globals<R>,
-  lossy = false,
-): Effect.Effect<Result, never, R> =>
-  finishExecution(startProgram({ prepared, limits, hooks, globals, lossy }, code, bindings).run())
-
 /** A program ready to run on the VM: nothing runs until `run`. */
 export const startProgram = <R>(
   setup: Setup<R>,
diff --git a/packages/codemode/src/vm/runtime/extensions.ts b/packages/codemode/src/runtime/extensions.ts
similarity index 99%
rename from packages/codemode/src/vm/runtime/extensions.ts
rename to packages/codemode/src/runtime/extensions.ts
index 1d335deba86..dc6f776f203 100644
--- a/packages/codemode/src/vm/runtime/extensions.ts
+++ b/packages/codemode/src/runtime/extensions.ts
@@ -1,6 +1,6 @@
 import { Effect } from "effect"
-import { type Extension, isAsync } from "../../extension.js"
-import { hooked } from "../../tool-runtime.js"
+import { type Extension, isAsync } from "../extension.js"
+import { hooked } from "../tool-runtime.js"
 import { errorMessage, errorType } from "./errors.js"
 import type { Interpreter } from "./interpreter.js"
 import { createErrorValue } from "./intrinsics.js"
diff --git a/packages/codemode/src/vm/runtime/generators.ts b/packages/codemode/src/runtime/generators.ts
similarity index 100%
rename from packages/codemode/src/vm/runtime/generators.ts
rename to packages/codemode/src/runtime/generators.ts
diff --git a/packages/codemode/src/vm/runtime/globals.ts b/packages/codemode/src/runtime/globals.ts
similarity index 99%
rename from packages/codemode/src/vm/runtime/globals.ts
rename to packages/codemode/src/runtime/globals.ts
index 6e5c3a31893..6909da9d0a1 100644
--- a/packages/codemode/src/vm/runtime/globals.ts
+++ b/packages/codemode/src/runtime/globals.ts
@@ -15,7 +15,7 @@ import { headersGlobal } from "../stdlib/headers.js"
 import { iteratorGlobals } from "../stdlib/iterator.js"
 import { coercion } from "../stdlib/value.js"
 import { base64Global, cryptoGlobal, structuredCloneGlobal } from "../stdlib/web.js"
-import { ToolReference } from "../../tool-runtime.js"
+import { ToolReference } from "../tool-runtime.js"
 import { errorGlobal } from "./errors.js"
 import { errorTypes } from "./intrinsics.js"
 import { constants, constructor, methods, native, receiver } from "./native.js"
diff --git a/packages/codemode/src/vm/runtime/interpreter.ts b/packages/codemode/src/runtime/interpreter.ts
similarity index 98%
rename from packages/codemode/src/vm/runtime/interpreter.ts
rename to packages/codemode/src/runtime/interpreter.ts
index 8522a6e2b81..f546d804600 100644
--- a/packages/codemode/src/vm/runtime/interpreter.ts
+++ b/packages/codemode/src/runtime/interpreter.ts
@@ -1,4 +1,4 @@
-import type { ToolRuntime } from "../../tool-runtime.js"
+import type { ToolRuntime } from "../tool-runtime.js"
 import type { ExtensionRequest } from "../scheduler.js"
 import type { HostBridge } from "../snapshot/codec.js"
 import { Vm } from "../vm.js"
diff --git a/packages/codemode/src/vm/runtime/intrinsic-names.ts b/packages/codemode/src/runtime/intrinsic-names.ts
similarity index 100%
rename from packages/codemode/src/vm/runtime/intrinsic-names.ts
rename to packages/codemode/src/runtime/intrinsic-names.ts
diff --git a/packages/codemode/src/vm/runtime/intrinsics.ts b/packages/codemode/src/runtime/intrinsics.ts
similarity index 100%
rename from packages/codemode/src/vm/runtime/intrinsics.ts
rename to packages/codemode/src/runtime/intrinsics.ts
diff --git a/packages/codemode/src/vm/runtime/limits.ts b/packages/codemode/src/runtime/limits.ts
similarity index 100%
rename from packages/codemode/src/vm/runtime/limits.ts
rename to packages/codemode/src/runtime/limits.ts
diff --git a/packages/codemode/src/vm/runtime/model.ts b/packages/codemode/src/runtime/model.ts
similarity index 98%
rename from packages/codemode/src/vm/runtime/model.ts
rename to packages/codemode/src/runtime/model.ts
index bbdccc41ccf..e40187d78cb 100644
--- a/packages/codemode/src/vm/runtime/model.ts
+++ b/packages/codemode/src/runtime/model.ts
@@ -1,6 +1,6 @@
 import type { Node } from "acorn"
 import type { ErrorType } from "./intrinsics.js"
-import type { DiagnosticKind } from "../../codemode.js"
+import type { DiagnosticKind } from "../codemode.js"
 import type { ErrorObj, Value } from "./objects.js"
 
 /** Any parsed node; the compiler narrows on `type`, and diagnostics read `loc`. */
diff --git a/packages/codemode/src/vm/runtime/modules.ts b/packages/codemode/src/runtime/modules.ts
similarity index 100%
rename from packages/codemode/src/vm/runtime/modules.ts
rename to packages/codemode/src/runtime/modules.ts
diff --git a/packages/codemode/src/vm/runtime/native.ts b/packages/codemode/src/runtime/native.ts
similarity index 100%
rename from packages/codemode/src/vm/runtime/native.ts
rename to packages/codemode/src/runtime/native.ts
diff --git a/packages/codemode/src/vm/runtime/objects.ts b/packages/codemode/src/runtime/objects.ts
similarity index 99%
rename from packages/codemode/src/vm/runtime/objects.ts
rename to packages/codemode/src/runtime/objects.ts
index cef4d7ae3af..ad09b37256b 100644
--- a/packages/codemode/src/vm/runtime/objects.ts
+++ b/packages/codemode/src/runtime/objects.ts
@@ -1,4 +1,4 @@
-import { ToolReference } from "../../tool-runtime.js"
+import { ToolReference } from "../tool-runtime.js"
 import type { Builtins } from "./intrinsics.js"
 import { checkArrayLength } from "./limits.js"
 import {
diff --git a/packages/codemode/src/vm/runtime/operations.ts b/packages/codemode/src/runtime/operations.ts
similarity index 99%
rename from packages/codemode/src/vm/runtime/operations.ts
rename to packages/codemode/src/runtime/operations.ts
index 01cf75ca039..93d772b72e8 100644
--- a/packages/codemode/src/vm/runtime/operations.ts
+++ b/packages/codemode/src/runtime/operations.ts
@@ -1,5 +1,5 @@
 import type { Expression, MemberExpression, NewExpression, Super } from "acorn"
-import { ToolReference } from "../../tool-runtime.js"
+import { ToolReference } from "../tool-runtime.js"
 import { type AstNode, invalidData, typeError } from "./model.js"
 import { checkStringLength } from "./limits.js"
 import { locate } from "./errors.js"
diff --git a/packages/codemode/src/vm/runtime/promises.ts b/packages/codemode/src/runtime/promises.ts
similarity index 100%
rename from packages/codemode/src/vm/runtime/promises.ts
rename to packages/codemode/src/runtime/promises.ts
diff --git a/packages/codemode/src/vm/runtime/references.ts b/packages/codemode/src/runtime/references.ts
similarity index 97%
rename from packages/codemode/src/vm/runtime/references.ts
rename to packages/codemode/src/runtime/references.ts
index 05cf8427f6e..c2c4a25bcd5 100644
--- a/packages/codemode/src/vm/runtime/references.ts
+++ b/packages/codemode/src/runtime/references.ts
@@ -1,4 +1,4 @@
-import { ToolReference } from "../../tool-runtime.js"
+import { ToolReference } from "../tool-runtime.js"
 import { invalidData } from "./model.js"
 import { Callable, getOwn, isRuntimeReference, Obj, Opaque, ownKeys, type Value } from "./objects.js"
 
diff --git a/packages/codemode/src/vm/runtime/signals.ts b/packages/codemode/src/runtime/signals.ts
similarity index 100%
rename from packages/codemode/src/vm/runtime/signals.ts
rename to packages/codemode/src/runtime/signals.ts
diff --git a/packages/codemode/src/vm/runtime/source.ts b/packages/codemode/src/runtime/source.ts
similarity index 100%
rename from packages/codemode/src/vm/runtime/source.ts
rename to packages/codemode/src/runtime/source.ts
diff --git a/packages/codemode/src/vm/runtime/table.ts b/packages/codemode/src/runtime/table.ts
similarity index 100%
rename from packages/codemode/src/vm/runtime/table.ts
rename to packages/codemode/src/runtime/table.ts
diff --git a/packages/codemode/src/scan.ts b/packages/codemode/src/scan.ts
index 4313acb11c4..3e6d499e331 100644
--- a/packages/codemode/src/scan.ts
+++ b/packages/codemode/src/scan.ts
@@ -1,8 +1,8 @@
 import type { AnyNode, BlockStatement, ModuleDeclaration, Pattern, Program, Statement } from "acorn"
 import { Result } from "effect"
 import type { Diagnostic } from "./codemode.js"
-import { parseProgram } from "./vm/runtime/execute.js"
-import { formatLocation } from "./vm/runtime/model.js"
+import { parseProgram } from "./runtime/execute.js"
+import { formatLocation } from "./runtime/model.js"
 
 /**
  * Extracts every `tools.<path>` referenced by a Code Mode program, in first-seen order. Fails on syntax errors,
diff --git a/packages/codemode/src/vm/scheduler.ts b/packages/codemode/src/scheduler.ts
similarity index 99%
rename from packages/codemode/src/vm/scheduler.ts
rename to packages/codemode/src/scheduler.ts
index 9de0cddd576..3d372013db8 100644
--- a/packages/codemode/src/vm/scheduler.ts
+++ b/packages/codemode/src/scheduler.ts
@@ -1,5 +1,5 @@
 import type { Json } from "./data.js"
-import type { ExtensionInvocation } from "../tool-runtime.js"
+import type { ExtensionInvocation } from "./tool-runtime.js"
 import { locate } from "./runtime/errors.js"
 import type { AstNode } from "./runtime/model.js"
 import type { Callable, Cursor, GeneratorObj, Obj, PromiseObj, Value } from "./runtime/objects.js"
diff --git a/packages/codemode/src/vm/snapshot.ts b/packages/codemode/src/snapshot.ts
similarity index 99%
rename from packages/codemode/src/vm/snapshot.ts
rename to packages/codemode/src/snapshot.ts
index a61d0e920eb..cc8c5b7835e 100644
--- a/packages/codemode/src/vm/snapshot.ts
+++ b/packages/codemode/src/snapshot.ts
@@ -1,4 +1,4 @@
-import packageJson from "../../package.json" with { type: "json" }
+import packageJson from "../package.json" with { type: "json" }
 import type { Interruption } from "./runtime/signals.js"
 import { staticNames, unchanged } from "./runtime/intrinsic-names.js"
 import { Fn, Obj } from "./runtime/objects.js"
diff --git a/packages/codemode/src/vm/snapshot/codec.ts b/packages/codemode/src/snapshot/codec.ts
similarity index 98%
rename from packages/codemode/src/vm/snapshot/codec.ts
rename to packages/codemode/src/snapshot/codec.ts
index f48a0291879..4345a199dfa 100644
--- a/packages/codemode/src/vm/snapshot/codec.ts
+++ b/packages/codemode/src/snapshot/codec.ts
@@ -39,8 +39,8 @@ import { deleted, OrderedTable } from "../runtime/table.js"
 import { AsyncFromSyncIterator } from "../generators.js"
 import { HostCall, Resolving } from "../scheduler.js"
 import { TextDecoderObj } from "../stdlib/bytes.js"
-import { ToolError, toolError } from "../../tool-error.js"
-import { ToolReference, ToolRuntimeError } from "../../tool-runtime.js"
+import { ToolError, toolError } from "../tool-error.js"
+import { ToolReference, ToolRuntimeError } from "../tool-runtime.js"
 
 // A graph codec for a run's state: every object reachable from the roots becomes one record, so identity, sharing,
 // and cycles survive, and every value inside a record is tagged JSON. Built-ins, AST nodes, bytecode, and the VM's
@@ -57,7 +57,7 @@ export type Json = null | boolean | number | string | ReadonlyArray<Json> | { re
  * - `["s", name]` an interpreter symbol;
  * - `["i", name]` a built-in or host global, unchanged since the runtime was made;
  * - `["a", source, index]` an AST node (a call site, an error's location);
- * - `["x", data]` something the engine names itself (the VM's compiled code, by source and function index);
+ * - `["x", data]` something the VM names itself (compiled code, by source and function index);
  * - `["r", id]` another record.
  */
 export type Encoded = string | number | boolean | null | ReadonlyArray<Json>
@@ -110,9 +110,9 @@ export type EncodeEnv = {
   readonly lost: Array<string>
   readonly strict: boolean
   readonly hosts?: HostBridge | undefined
-  /** More classes to save, an engine's own (the VM's frames and closures), after the built-in ones. */
+  /** More classes to save (the VM's frames and closures), after the built-in ones. */
   readonly specs?: ReadonlyArray<ClassSpec> | undefined
-  /** The data an engine names an object or symbol by, saved as `["x", data]`, instead of copying it. */
+  /** The data the VM names an object or symbol by, saved as `["x", data]`, instead of copying it. */
   readonly external?: ((value: object | symbol) => Json | undefined) | undefined
 }
 
diff --git a/packages/codemode/src/vm/snapshot/snapshot.ts b/packages/codemode/src/snapshot/snapshot.ts
similarity index 97%
rename from packages/codemode/src/vm/snapshot/snapshot.ts
rename to packages/codemode/src/snapshot/snapshot.ts
index 238bafdff4f..c911ac61f79 100644
--- a/packages/codemode/src/vm/snapshot/snapshot.ts
+++ b/packages/codemode/src/snapshot/snapshot.ts
@@ -1,5 +1,5 @@
 import type { Interpreter } from "../runtime/interpreter.js"
-import type { ToolCall } from "../../tool-runtime.js"
+import type { ToolCall } from "../tool-runtime.js"
 import { type Encoded, type Record, SnapshotError } from "./codec.js"
 
 export { SnapshotError }
@@ -16,7 +16,7 @@ export const fromBytes = (bytes: Uint8Array): unknown => {
   }
 }
 
-/** The snapshot format this build writes and reads: the bytecode VM's (see `src/vm/snapshot.ts`). */
+/** The snapshot format this build writes and reads (see `src/snapshot.ts`). */
 export const FORMAT = 2
 
 /**
diff --git a/packages/codemode/src/vm/stdlib/array.ts b/packages/codemode/src/stdlib/array.ts
similarity index 99%
rename from packages/codemode/src/vm/stdlib/array.ts
rename to packages/codemode/src/stdlib/array.ts
index 1799066113f..fbd300a82e4 100644
--- a/packages/codemode/src/vm/stdlib/array.ts
+++ b/packages/codemode/src/stdlib/array.ts
@@ -23,7 +23,7 @@ import {
 import { describeValue, rejectCircularInsertion } from "../runtime/references.js"
 import { requireCallback, withPrimitives } from "../runtime/callback.js"
 import type { Interpreter } from "../runtime/interpreter.js"
-import { compareText } from "../../tool-runtime.js"
+import { compareText } from "../tool-runtime.js"
 
 const arrayLikeSource = (source: Value): { readonly length: number; readonly source: Obj } => {
   // JS would treat a promise as an empty array-like; that would hide a missing `await`.
diff --git a/packages/codemode/src/vm/stdlib/bytes.ts b/packages/codemode/src/stdlib/bytes.ts
similarity index 100%
rename from packages/codemode/src/vm/stdlib/bytes.ts
rename to packages/codemode/src/stdlib/bytes.ts
diff --git a/packages/codemode/src/vm/stdlib/collections.ts b/packages/codemode/src/stdlib/collections.ts
similarity index 100%
rename from packages/codemode/src/vm/stdlib/collections.ts
rename to packages/codemode/src/stdlib/collections.ts
diff --git a/packages/codemode/src/vm/stdlib/console.ts b/packages/codemode/src/stdlib/console.ts
similarity index 98%
rename from packages/codemode/src/vm/stdlib/console.ts
rename to packages/codemode/src/stdlib/console.ts
index c4e4f7fd68c..34ff060368e 100644
--- a/packages/codemode/src/vm/stdlib/console.ts
+++ b/packages/codemode/src/stdlib/console.ts
@@ -1,6 +1,6 @@
 import { type Method, methods } from "../runtime/native.js"
 import { entries, get, Arr, Obj, type Value } from "../runtime/objects.js"
-import { ToolReference } from "../../tool-runtime.js"
+import { ToolReference } from "../tool-runtime.js"
 import { containsOpaqueReference } from "../runtime/references.js"
 import type { Interpreter } from "../runtime/interpreter.js"
 
diff --git a/packages/codemode/src/vm/stdlib/date.ts b/packages/codemode/src/stdlib/date.ts
similarity index 100%
rename from packages/codemode/src/vm/stdlib/date.ts
rename to packages/codemode/src/stdlib/date.ts
diff --git a/packages/codemode/src/vm/stdlib/headers.ts b/packages/codemode/src/stdlib/headers.ts
similarity index 100%
rename from packages/codemode/src/vm/stdlib/headers.ts
rename to packages/codemode/src/stdlib/headers.ts
diff --git a/packages/codemode/src/vm/stdlib/iterator.ts b/packages/codemode/src/stdlib/iterator.ts
similarity index 100%
rename from packages/codemode/src/vm/stdlib/iterator.ts
rename to packages/codemode/src/stdlib/iterator.ts
diff --git a/packages/codemode/src/vm/stdlib/json.ts b/packages/codemode/src/stdlib/json.ts
similarity index 100%
rename from packages/codemode/src/vm/stdlib/json.ts
rename to packages/codemode/src/stdlib/json.ts
diff --git a/packages/codemode/src/vm/stdlib/math.ts b/packages/codemode/src/stdlib/math.ts
similarity index 100%
rename from packages/codemode/src/vm/stdlib/math.ts
rename to packages/codemode/src/stdlib/math.ts
diff --git a/packages/codemode/src/vm/stdlib/number.ts b/packages/codemode/src/stdlib/number.ts
similarity index 100%
rename from packages/codemode/src/vm/stdlib/number.ts
rename to packages/codemode/src/stdlib/number.ts
diff --git a/packages/codemode/src/vm/stdlib/object.ts b/packages/codemode/src/stdlib/object.ts
similarity index 99%
rename from packages/codemode/src/vm/stdlib/object.ts
rename to packages/codemode/src/stdlib/object.ts
index 09e8482a6a1..60886115eaa 100644
--- a/packages/codemode/src/vm/stdlib/object.ts
+++ b/packages/codemode/src/stdlib/object.ts
@@ -22,7 +22,7 @@ import { primitivePrototype } from "../runtime/intrinsics.js"
 import { describeValue, rejectCircularInsertion } from "../runtime/references.js"
 import { invokeMethod } from "../runtime/callback.js"
 import type { Interpreter } from "../runtime/interpreter.js"
-import { ToolReference } from "../../tool-runtime.js"
+import { ToolReference } from "../tool-runtime.js"
 
 // ToObject for enumeration.
 export const enumerableSource = <R>(ctx: Interpreter<R>, label: string, value: Value, node?: AstNode): Obj => {
diff --git a/packages/codemode/src/vm/stdlib/regexp.ts b/packages/codemode/src/stdlib/regexp.ts
similarity index 100%
rename from packages/codemode/src/vm/stdlib/regexp.ts
rename to packages/codemode/src/stdlib/regexp.ts
diff --git a/packages/codemode/src/vm/stdlib/string.ts b/packages/codemode/src/stdlib/string.ts
similarity index 100%
rename from packages/codemode/src/vm/stdlib/string.ts
rename to packages/codemode/src/stdlib/string.ts
diff --git a/packages/codemode/src/vm/stdlib/url.ts b/packages/codemode/src/stdlib/url.ts
similarity index 100%
rename from packages/codemode/src/vm/stdlib/url.ts
rename to packages/codemode/src/stdlib/url.ts
diff --git a/packages/codemode/src/vm/stdlib/value.ts b/packages/codemode/src/stdlib/value.ts
similarity index 100%
rename from packages/codemode/src/vm/stdlib/value.ts
rename to packages/codemode/src/stdlib/value.ts
diff --git a/packages/codemode/src/vm/stdlib/web.ts b/packages/codemode/src/stdlib/web.ts
similarity index 98%
rename from packages/codemode/src/vm/stdlib/web.ts
rename to packages/codemode/src/stdlib/web.ts
index 4c18668d973..75b62f8c772 100644
--- a/packages/codemode/src/vm/stdlib/web.ts
+++ b/packages/codemode/src/stdlib/web.ts
@@ -24,7 +24,7 @@ import {
 import { createErrorValue, isErrorType } from "../runtime/intrinsics.js"
 import { describeValue } from "../runtime/references.js"
 import type { Interpreter } from "../runtime/interpreter.js"
-import { ToolReference } from "../../tool-runtime.js"
+import { ToolReference } from "../tool-runtime.js"
 
 // WebIDL DOMString conversion: a missing argument is a TypeError, anything else stringifies. Invalid input is a
 // TypeError as well; browsers throw a DOMException named InvalidCharacterError, which CodeMode does not have.
diff --git a/packages/codemode/src/tool-runtime.ts b/packages/codemode/src/tool-runtime.ts
index 26823b10c53..8910a44c6b8 100644
--- a/packages/codemode/src/tool-runtime.ts
+++ b/packages/codemode/src/tool-runtime.ts
@@ -1,5 +1,5 @@
 import { Cause, Effect, Exit, Formatter, Schema } from "effect"
-import type { Json } from "./vm/data.js"
+import type { Json } from "./data.js"
 import type { DiagnosticKind } from "./codemode.js"
 import { toolError } from "./tool-error.js"
 import {
diff --git a/packages/codemode/src/vm/vm.ts b/packages/codemode/src/vm.ts
similarity index 99%
rename from packages/codemode/src/vm/vm.ts
rename to packages/codemode/src/vm.ts
index de0842903b7..fc6003ed8d1 100644
--- a/packages/codemode/src/vm/vm.ts
+++ b/packages/codemode/src/vm.ts
@@ -1,5 +1,5 @@
 import { parse, type Expression, type MemberExpression, type NewExpression } from "acorn"
-import type { Diagnostic } from "../codemode.js"
+import type { Diagnostic } from "./codemode.js"
 import { conversions } from "./runtime/callback.js"
 import { locate, materialize } from "./runtime/errors.js"
 import type { Interpreter } from "./runtime/interpreter.js"
@@ -81,7 +81,7 @@ import type { HostCall, Stop } from "./scheduler.js"
 import { compiledPrelude } from "./prelude/prelude.js"
 import { constructRegExp } from "./stdlib/regexp.js"
 import { enumerableSource } from "./stdlib/object.js"
-import { ToolReference } from "../tool-runtime.js"
+import { ToolReference } from "./tool-runtime.js"
 import { registerAsyncIntrinsics, type SettlingTarget, VmScheduler } from "./async.js"
 import type { Code } from "./code.js"
 import { type CaptureOptions, captureVm, type RestoreOptions, restoreVm } from "./snapshot.js"
diff --git a/packages/codemode/test/array-callbacks-test262.test.ts b/packages/codemode/test/array-callbacks-test262.test.ts
index a538072bfe6..4dd98009516 100644
--- a/packages/codemode/test/array-callbacks-test262.test.ts
+++ b/packages/codemode/test/array-callbacks-test262.test.ts
@@ -56,7 +56,7 @@
  */
 import { describe, expect, test } from "bun:test"
 import { Effect } from "effect"
-import { CodeMode } from "./lib/index.js"
+import { CodeMode } from "../src/index.js"
 
 const value = async (code: string) => {
   const result = await Effect.runPromise(CodeMode.execute({ code, tools: {} }))
diff --git a/packages/codemode/test/array-core-test262.test.ts b/packages/codemode/test/array-core-test262.test.ts
index 1b436b5f3da..b1c3d67447a 100644
--- a/packages/codemode/test/array-core-test262.test.ts
+++ b/packages/codemode/test/array-core-test262.test.ts
@@ -69,7 +69,7 @@
  */
 import { describe, expect, test } from "bun:test"
 import { Effect } from "effect"
-import { CodeMode } from "./lib/index.js"
+import { CodeMode } from "../src/index.js"
 
 const value = async (code: string) => {
   const result = await Effect.runPromise(CodeMode.execute({ code, tools: {} }))
diff --git a/packages/codemode/test/vm/build-id.test.ts b/packages/codemode/test/build-id.test.ts
similarity index 87%
rename from packages/codemode/test/vm/build-id.test.ts
rename to packages/codemode/test/build-id.test.ts
index cac3e5ad9b3..27c84b726e7 100644
--- a/packages/codemode/test/vm/build-id.test.ts
+++ b/packages/codemode/test/build-id.test.ts
@@ -4,7 +4,7 @@ import path from "node:path"
 // The snapshot build id hashes only the package's own bytecode, codecs, and built-ins, so it is the same in every
 // process, whatever it imported first.
 
-const root = path.join(import.meta.dir, "../..")
+const root = path.join(import.meta.dir, "..")
 
 const output = async (command: Array<string>) => {
   const child = Bun.spawn(command, { cwd: root, stdout: "pipe", stderr: "pipe" })
@@ -15,7 +15,7 @@ const output = async (command: Array<string>) => {
 
 describe("build id", () => {
   test("the build id is the same whatever a process imported first", async () => {
-    const fixture = path.join(import.meta.dir, "../fixtures/build-id.ts")
+    const fixture = path.join(import.meta.dir, "fixtures/build-id.ts")
     const ids = await Promise.all(
       [[], ["--preload", "./test/test262/run.ts"], ["--preload", "./src/index.ts"]].map((preload) =>
         output(["bun", ...preload, fixture]),
@@ -28,6 +28,6 @@ describe("build id", () => {
 
   // A process with the test262 harness loaded saves the run; the child that resumes it has not loaded it.
   test("a run saved with the test262 harness loaded resumes in another process", async () => {
-    await output(["bun", "test", "--preload", "./test/test262/run.ts", "test/vm/suspend.test.ts", "-t", "another process"])
+    await output(["bun", "test", "--preload", "./test/test262/run.ts", "test/suspend.test.ts", "-t", "another process"])
   }, 15_000)
 })
diff --git a/packages/codemode/test/vm/limits.test.ts b/packages/codemode/test/bytecode-limits.test.ts
similarity index 97%
rename from packages/codemode/test/vm/limits.test.ts
rename to packages/codemode/test/bytecode-limits.test.ts
index bcb129767b2..7834457af05 100644
--- a/packages/codemode/test/vm/limits.test.ts
+++ b/packages/codemode/test/bytecode-limits.test.ts
@@ -1,13 +1,13 @@
 import { describe, expect, test } from "bun:test"
-import { createBuiltins } from "../../src/vm/runtime/intrinsics.js"
-import { Interpreter } from "../../src/vm/runtime/interpreter.js"
-import type { ToolRuntime } from "../../src/tool-runtime.js"
-import { CodeBuilder, CodeSizeOverflow, hashOf } from "../../src/vm/code.js"
-import { compileSource } from "../../src/vm/compiler/compile.js"
-import { CodeFlags, EMPTY_CELLS, Op, packWord, PutKind } from "../../src/vm/opcodes.js"
-import { Mode } from "../../src/vm/vm.js"
-import { parseVmSource, type RunOptions, runProgram } from "./run.js"
-import { verifyAll, verifyCode } from "./verify.js"
+import { createBuiltins } from "../src/runtime/intrinsics.js"
+import { Interpreter } from "../src/runtime/interpreter.js"
+import type { ToolRuntime } from "../src/tool-runtime.js"
+import { CodeBuilder, CodeSizeOverflow, hashOf } from "../src/code.js"
+import { compileSource } from "../src/compiler/compile.js"
+import { CodeFlags, EMPTY_CELLS, Op, packWord, PutKind } from "../src/opcodes.js"
+import { Mode } from "../src/vm.js"
+import { parseVmSource, type RunOptions, runProgram } from "./run-program.js"
+import { verifyAll, verifyCode } from "./verify-bytecode.js"
 
 const emptyTools = {
   calls: [],
@@ -534,8 +534,9 @@ describe("per-function wide jumps past 65,535 words and snapshot round-trips", (
       mainRes: [21, 10, expectedPadA * 2, 378, 13, 7, "late-reject", "ok"],
       gSteps: [1, 10, 20, expectedGenPad + 4, 18],
     })
-  })
+  }, 15_000)
 
+  // Compiling a >65,535-word program and round-tripping 8 full snapshots takes ~8-9s on loaded Windows runners.
   test("top-level script >65,535 words runs correctly and survives snapshot round-trips at pc > 65,535", () => {
     const src = `
       function hoistedTop(n) { return n + 42 }
@@ -602,5 +603,5 @@ describe("per-function wide jumps past 65,535 words and snapshot round-trips", (
     expect(roundTripped).toEqual({ ok: true, value: expected, toolCalls: [] })
     expect(trips).toBeGreaterThan(2)
     expect(sawHighPc).toBe(true)
-  })
+  }, 15_000)
 })
diff --git a/packages/codemode/test/callbacks.test.ts b/packages/codemode/test/callbacks.test.ts
index 5b736205f8f..9722ae19a1a 100644
--- a/packages/codemode/test/callbacks.test.ts
+++ b/packages/codemode/test/callbacks.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, test } from "bun:test"
 import { Effect, Schema } from "effect"
-import { CodeMode, Tool } from "./lib/index.js"
+import { CodeMode, Tool } from "../src/index.js"
 
 // Callback acceptance is one gate shared by array methods, sort, string replacers,
 // Array.from mappers, Map/Set/URLSearchParams forEach, and promise reactions:
diff --git a/packages/codemode/test/codemode.test.ts b/packages/codemode/test/codemode.test.ts
index 4258ffa9c83..c9f4cd10015 100644
--- a/packages/codemode/test/codemode.test.ts
+++ b/packages/codemode/test/codemode.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, test } from "bun:test"
 import { Cause, Effect, Schema } from "effect"
-import { CodeMode, Extension, Tool, toolError } from "./lib/index.js"
+import { CodeMode, Extension, Tool, toolError } from "../src/index.js"
 
 const run = (tool: Tool.Tool<never>) =>
   Effect.runPromise(CodeMode.make({ tools: { host: { call: tool } } }).execute("return await tools.host.call({})"))
diff --git a/packages/codemode/test/constructor-test262.test.ts b/packages/codemode/test/constructor-test262.test.ts
index 368e71a883d..c038f3f21c3 100644
--- a/packages/codemode/test/constructor-test262.test.ts
+++ b/packages/codemode/test/constructor-test262.test.ts
@@ -14,7 +14,7 @@
  */
 import { describe, expect, test } from "bun:test"
 import { Effect } from "effect"
-import { CodeMode } from "./lib/index.js"
+import { CodeMode } from "../src/index.js"
 
 const value = async (code: string) => {
   const result = await Effect.runPromise(CodeMode.execute({ code, tools: {} }))
diff --git a/packages/codemode/test/date-test262.test.ts b/packages/codemode/test/date-test262.test.ts
index 04c5256c417..ffda8cef4bf 100644
--- a/packages/codemode/test/date-test262.test.ts
+++ b/packages/codemode/test/date-test262.test.ts
@@ -44,7 +44,7 @@
  */
 import { describe, expect, test } from "bun:test"
 import { Effect } from "effect"
-import { CodeMode } from "./lib/index.js"
+import { CodeMode } from "../src/index.js"
 
 const value = async (code: string) => {
   const result = await Effect.runPromise(CodeMode.execute({ code, tools: {} }))
diff --git a/packages/codemode/test/enumeration.test.ts b/packages/codemode/test/enumeration.test.ts
index e5feef46d5c..c46b6048d5b 100644
--- a/packages/codemode/test/enumeration.test.ts
+++ b/packages/codemode/test/enumeration.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, test } from "bun:test"
 import { Effect, Schema } from "effect"
-import { CodeMode, Tool } from "./lib/index.js"
+import { CodeMode, Tool } from "../src/index.js"
 
 // Key enumeration: Object.keys and for...in share one surface over plain objects, arrays
 // (index strings), and tool references (namespace/tool names from the supplied tools), so a
diff --git a/packages/codemode/test/errors.test.ts b/packages/codemode/test/errors.test.ts
index 4aa1636c288..8cbb483c247 100644
--- a/packages/codemode/test/errors.test.ts
+++ b/packages/codemode/test/errors.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, test } from "bun:test"
 import { Effect } from "effect"
-import { CodeMode } from "./lib/index.js"
+import { CodeMode } from "../src/index.js"
 
 // One failure is one program error object, and rethrowing it keeps the diagnostic it started with.
 const run = (code: string) => Effect.runPromise(CodeMode.execute({ code, tools: {} }))
diff --git a/packages/codemode/test/extensions.test.ts b/packages/codemode/test/extensions.test.ts
index 1dda1501431..5e66727559e 100644
--- a/packages/codemode/test/extensions.test.ts
+++ b/packages/codemode/test/extensions.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, test } from "bun:test"
 import { Context, Effect, Schema } from "effect"
-import { CodeMode, Extension, Tool } from "./lib/index.js"
+import { CodeMode, Extension, Tool } from "../src/index.js"
 
 const held: Array<unknown> = []
 const config = { retries: 3, nested: { deep: true } }
diff --git a/packages/codemode/test/fixtures/build-id.ts b/packages/codemode/test/fixtures/build-id.ts
index 47a2a0f4a35..22b5b1018d6 100644
--- a/packages/codemode/test/fixtures/build-id.ts
+++ b/packages/codemode/test/fixtures/build-id.ts
@@ -1,8 +1,8 @@
 // Prints this process's snapshot build id, from a runtime made with as few of the package's modules as it takes, so
 // the id can be compared across entry points (`bun --preload <module> build-id.ts`).
-import { Interpreter } from "../../src/vm/runtime/interpreter.js"
-import { createBuiltins } from "../../src/vm/runtime/intrinsics.js"
-import { buildId } from "../../src/vm/snapshot.js"
+import { Interpreter } from "../../src/runtime/interpreter.js"
+import { createBuiltins } from "../../src/runtime/intrinsics.js"
+import { buildId } from "../../src/snapshot.js"
 import { ToolRuntime } from "../../src/tool-runtime.js"
 
 new Interpreter({ tools: ToolRuntime.make(ToolRuntime.prepare({}), undefined, {}), builtins: createBuiltins() })
diff --git a/packages/codemode/test/fixtures/prelude-roundtrip.ts b/packages/codemode/test/fixtures/prelude-roundtrip.ts
index 026c320919d..e3f52f35f73 100644
--- a/packages/codemode/test/fixtures/prelude-roundtrip.ts
+++ b/packages/codemode/test/fixtures/prelude-roundtrip.ts
@@ -2,9 +2,9 @@
 // prelude frame was on the stack.
 import { Effect } from "effect"
 import { CodeMode } from "../../src/index.js"
-import { CodeFlags } from "../../src/vm/opcodes.js"
-import { setRoundTrip } from "../../src/vm/runtime/execute.js"
-import { Vm } from "../../src/vm/vm.js"
+import { CodeFlags } from "../../src/opcodes.js"
+import { setRoundTrip } from "../../src/runtime/execute.js"
+import { Vm } from "../../src/vm.js"
 
 setRoundTrip(true)
 
diff --git a/packages/codemode/test/for-await-test262.test.ts b/packages/codemode/test/for-await-test262.test.ts
index 0863b1827c7..fcbbcb85ccb 100644
--- a/packages/codemode/test/for-await-test262.test.ts
+++ b/packages/codemode/test/for-await-test262.test.ts
@@ -14,7 +14,7 @@
  */
 import { describe, expect, test } from "bun:test"
 import { Effect } from "effect"
-import { CodeMode } from "./lib/index.js"
+import { CodeMode } from "../src/index.js"
 
 const execute = (code: string) => Effect.runPromise(CodeMode.execute({ code, tools: {} }))
 
diff --git a/packages/codemode/test/generator-test262.test.ts b/packages/codemode/test/generator-test262.test.ts
index b8569713ddb..9afa501c215 100644
--- a/packages/codemode/test/generator-test262.test.ts
+++ b/packages/codemode/test/generator-test262.test.ts
@@ -12,7 +12,7 @@
  */
 import { describe, expect, test } from "bun:test"
 import { Effect } from "effect"
-import { CodeMode } from "./lib/index.js"
+import { CodeMode } from "../src/index.js"
 
 const execute = (code: string) => Effect.runPromise(CodeMode.execute({ code, tools: {} }))
 
diff --git a/packages/codemode/test/groupby-test262.test.ts b/packages/codemode/test/groupby-test262.test.ts
index 152ec86bede..bf27ad846e9 100644
--- a/packages/codemode/test/groupby-test262.test.ts
+++ b/packages/codemode/test/groupby-test262.test.ts
@@ -30,7 +30,7 @@
  */
 import { describe, expect, test } from "bun:test"
 import { Effect } from "effect"
-import { CodeMode } from "./lib/index.js"
+import { CodeMode } from "../src/index.js"
 
 const execute = (code: string) => Effect.runPromise(CodeMode.execute({ code, tools: {} }))
 
diff --git a/packages/codemode/test/json-callbacks-test262.test.ts b/packages/codemode/test/json-callbacks-test262.test.ts
index 8a0e16efa34..384ec6ece4b 100644
--- a/packages/codemode/test/json-callbacks-test262.test.ts
+++ b/packages/codemode/test/json-callbacks-test262.test.ts
@@ -28,7 +28,7 @@
  */
 import { describe, expect, test } from "bun:test"
 import { Effect } from "effect"
-import { CodeMode } from "./lib/index.js"
+import { CodeMode } from "../src/index.js"
 
 const value = async (code: string) => {
   const result = await Effect.runPromise(CodeMode.execute({ code, tools: {} }))
diff --git a/packages/codemode/test/labeled-control-test262.test.ts b/packages/codemode/test/labeled-control-test262.test.ts
index 8d7196ca06e..37866b17cb4 100644
--- a/packages/codemode/test/labeled-control-test262.test.ts
+++ b/packages/codemode/test/labeled-control-test262.test.ts
@@ -12,7 +12,7 @@
  */
 import { describe, expect, test } from "bun:test"
 import { Effect } from "effect"
-import { CodeMode } from "./lib/index.js"
+import { CodeMode } from "../src/index.js"
 
 const execute = (code: string) => Effect.runPromise(CodeMode.execute({ code, tools: {} }))
 
diff --git a/packages/codemode/test/lexical-test262.test.ts b/packages/codemode/test/lexical-test262.test.ts
index 0666e6da650..6f67a9acb9b 100644
--- a/packages/codemode/test/lexical-test262.test.ts
+++ b/packages/codemode/test/lexical-test262.test.ts
@@ -26,7 +26,7 @@
  */
 import { describe, expect, test } from "bun:test"
 import { Effect } from "effect"
-import { CodeMode } from "./lib/index.js"
+import { CodeMode } from "../src/index.js"
 
 const value = async (code: string) => {
   const result = await Effect.runPromise(CodeMode.execute({ code, tools: {} }))
diff --git a/packages/codemode/test/lib/index.ts b/packages/codemode/test/lib/index.ts
deleted file mode 100644
index 53fe6d36e96..00000000000
--- a/packages/codemode/test/lib/index.ts
+++ /dev/null
@@ -1 +0,0 @@
-export * from "../../src/index.js"
diff --git a/packages/codemode/test/limits.test.ts b/packages/codemode/test/limits.test.ts
index 7cc035b3110..781089e398c 100644
--- a/packages/codemode/test/limits.test.ts
+++ b/packages/codemode/test/limits.test.ts
@@ -1,7 +1,7 @@
 import { describe, expect, test } from "bun:test"
 import { Cause, Deferred, Effect, Exit, Fiber, Schema } from "effect"
-import { CodeMode, Tool } from "./lib/index.js"
-import { MAX_ARRAY_LENGTH, MAX_PENDING_PROMISES, MAX_STRING_LENGTH } from "../src/vm/runtime/limits.js"
+import { CodeMode, Tool } from "../src/index.js"
+import { MAX_ARRAY_LENGTH, MAX_PENDING_PROMISES, MAX_STRING_LENGTH } from "../src/runtime/limits.js"
 
 const runtime = CodeMode.make({ tools: {} })
 
@@ -40,7 +40,7 @@ describe("one built-in cannot build an unbounded value", () => {
   })
 
   // split and matchAll share the same result check but must build ten million items first to reach it,
-  // which is too slow for CI.
+  // which is too slow for CI; flat() over MAX_ARRAY_LENGTH (10M) elements still needs a 15s budget on Windows.
   test("arrays: constructor, length, Array.from, concat, flat", async () => {
     expect(await value(`return Array(${A}).length`)).toBe(A)
     for (const code of [
@@ -54,7 +54,7 @@ describe("one built-in cannot build an unbounded value", () => {
         "RangeError: Invalid array length",
       )
     }
-  })
+  }, 15_000)
 
   test("promises: too many pending at once, while settled ones do not count", async () => {
     const n = MAX_PENDING_PROMISES
diff --git a/packages/codemode/test/new-expression.test.ts b/packages/codemode/test/new-expression.test.ts
index 1be0c5cd337..0beafad48fb 100644
--- a/packages/codemode/test/new-expression.test.ts
+++ b/packages/codemode/test/new-expression.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, test } from "bun:test"
 import { Effect, Schema } from "effect"
-import { CodeMode, Tool } from "./lib/index.js"
+import { CodeMode, Tool } from "../src/index.js"
 
 // `new` is supported syntax; only the callee decides whether construction succeeds. A callee without
 // construction support is a TypeError naming it, like JS, rather than an unsupported-syntax diagnostic
diff --git a/packages/codemode/test/object-coercion-test262.test.ts b/packages/codemode/test/object-coercion-test262.test.ts
index d89133ae5a5..adba9e8bd62 100644
--- a/packages/codemode/test/object-coercion-test262.test.ts
+++ b/packages/codemode/test/object-coercion-test262.test.ts
@@ -37,7 +37,7 @@
  */
 import { describe, expect, test } from "bun:test"
 import { Effect } from "effect"
-import { CodeMode } from "./lib/index.js"
+import { CodeMode } from "../src/index.js"
 
 const value = async (code: string) => {
   const result = await Effect.runPromise(CodeMode.execute({ code, tools: {} }))
diff --git a/packages/codemode/test/openapi.test.ts b/packages/codemode/test/openapi.test.ts
index 3a320385329..e82484ea6c9 100644
--- a/packages/codemode/test/openapi.test.ts
+++ b/packages/codemode/test/openapi.test.ts
@@ -1,7 +1,7 @@
 import { describe, expect, test } from "bun:test"
 import { Effect, Layer, Option } from "effect"
 import { HttpClient, HttpClientRequest, HttpClientResponse } from "effect/http"
-import { CodeMode, OpenAPI, Tool } from "./lib/index.js"
+import { CodeMode, OpenAPI, Tool } from "../src/index.js"
 import { inputTypeScript, outputTypeScript } from "../src/tool-schema.js"
 
 const baseUrl = "http://localhost:4096"
diff --git a/packages/codemode/test/parity.test.ts b/packages/codemode/test/parity.test.ts
index 4d7bd129f26..72b00a447a5 100644
--- a/packages/codemode/test/parity.test.ts
+++ b/packages/codemode/test/parity.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, test } from "bun:test"
 import { Effect } from "effect"
-import { CodeMode } from "./lib/index.js"
+import { CodeMode } from "../src/index.js"
 
 // Runs a CodeMode program with no host tools and returns the CodeMode.Result. These tests pin the
 // JS-parity behaviors for the "99% of ordinary defensive JavaScript just works" goal: cases where
diff --git a/packages/codemode/test/preload.ts b/packages/codemode/test/preload.ts
index aa8ac22ade7..2f099491715 100644
--- a/packages/codemode/test/preload.ts
+++ b/packages/codemode/test/preload.ts
@@ -1,5 +1,5 @@
-import { setRoundTrip } from "../src/vm/runtime/execute.js"
-import { nativeRule } from "../src/vm/runtime/objects.js"
+import { setRoundTrip } from "../src/runtime/execute.js"
+import { nativeRule } from "../src/runtime/objects.js"
 
 // Every test run checks that natives are made only with the intrinsics.
 nativeRule.check = true
diff --git a/packages/codemode/test/vm/prelude-bytecode.test.ts b/packages/codemode/test/prelude-bytecode.test.ts
similarity index 77%
rename from packages/codemode/test/vm/prelude-bytecode.test.ts
rename to packages/codemode/test/prelude-bytecode.test.ts
index 04d466f1588..1f8ea7daa9c 100644
--- a/packages/codemode/test/vm/prelude-bytecode.test.ts
+++ b/packages/codemode/test/prelude-bytecode.test.ts
@@ -1,10 +1,10 @@
 import { describe, expect, test } from "bun:test"
-import { compileBuiltins } from "../../script/prelude.js"
-import saved from "../../src/vm/prelude/bytecode.json" with { type: "json" }
-import { compiledPrelude } from "../../src/vm/prelude/prelude.js"
-import { hashOf } from "../../src/vm/code.js"
-import { getInternalPrelude } from "../../src/vm/internal-prelude.js"
-import { moduleUrl, runProgram } from "./run.js"
+import { compileBuiltins } from "../script/prelude.js"
+import saved from "../src/prelude/bytecode.json" with { type: "json" }
+import { compiledPrelude } from "../src/prelude/prelude.js"
+import { hashOf } from "../src/code.js"
+import { getInternalPrelude } from "../src/internal-prelude.js"
+import { moduleUrl, runProgram } from "./run-program.js"
 
 // The built-in sources are compiled ahead of time (script/prelude.ts); a process loads that bytecode instead.
 
@@ -25,8 +25,8 @@ describe("precompiled built-ins", () => {
     }
     // A fresh process runs a program that calls into the prelude, and its source is still unparsed.
     const script = `
-      import { runProgram } from ${moduleUrl("run.js")}
-      import { compiledPrelude } from ${moduleUrl("../../src/vm/prelude/prelude.js")}
+      import { runProgram } from ${moduleUrl("run-program.js")}
+      import { compiledPrelude } from ${moduleUrl("../src/prelude/prelude.js")}
       const result = runProgram("return [3, 1, 2].map((x) => x * 2).sort((a, b) => a - b)")
       console.log(JSON.stringify([result.ok && result.value, typeof compiledPrelude().codes[0].sourceObj.tree]))`
     const child = Bun.spawn(["bun", "-e", script], { stdout: "pipe", stderr: "inherit" })
diff --git a/packages/codemode/test/promise-test262.test.ts b/packages/codemode/test/promise-test262.test.ts
index 130c85770bf..d2b60659b2d 100644
--- a/packages/codemode/test/promise-test262.test.ts
+++ b/packages/codemode/test/promise-test262.test.ts
@@ -14,7 +14,7 @@
  */
 import { describe, expect, test } from "bun:test"
 import { Effect } from "effect"
-import { CodeMode } from "./lib/index.js"
+import { CodeMode } from "../src/index.js"
 
 const execute = (code: string) => Effect.runPromise(CodeMode.execute({ code, tools: {}, limits: { timeoutMs: 1_000 } }))
 
diff --git a/packages/codemode/test/promise.test.ts b/packages/codemode/test/promise.test.ts
index 4d84c77ec94..947e3a50d69 100644
--- a/packages/codemode/test/promise.test.ts
+++ b/packages/codemode/test/promise.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, test } from "bun:test"
 import { Cause, Deferred, Effect, Exit, Schema } from "effect"
-import { CodeMode, Tool, toolError } from "./lib/index.js"
+import { CodeMode, Tool, toolError } from "../src/index.js"
 
 // Wave 5 acceptance suite: first-class promise values. Un-awaited tool calls start eagerly as
 // host work, `await` settles them, Promise.all/allSettled/race/resolve/reject are
diff --git a/packages/codemode/test/regexp-math-test262.test.ts b/packages/codemode/test/regexp-math-test262.test.ts
index d12562d10b2..bd85d3ef2db 100644
--- a/packages/codemode/test/regexp-math-test262.test.ts
+++ b/packages/codemode/test/regexp-math-test262.test.ts
@@ -41,7 +41,7 @@
  */
 import { describe, expect, test } from "bun:test"
 import { Effect } from "effect"
-import { CodeMode } from "./lib/index.js"
+import { CodeMode } from "../src/index.js"
 
 const value = async (code: string) => {
   const result = await Effect.runPromise(CodeMode.execute({ code, tools: {} }))
diff --git a/packages/codemode/test/vm/resumable.test.ts b/packages/codemode/test/resumable.test.ts
similarity index 95%
rename from packages/codemode/test/vm/resumable.test.ts
rename to packages/codemode/test/resumable.test.ts
index 8ab9ad6492b..8bc794f4e3f 100644
--- a/packages/codemode/test/vm/resumable.test.ts
+++ b/packages/codemode/test/resumable.test.ts
@@ -1,16 +1,16 @@
 import { describe, expect, test } from "bun:test"
 import path from "node:path"
-import { parseProgram } from "../../src/vm/runtime/execute.js"
-import { Interpreter } from "../../src/vm/runtime/interpreter.js"
-import { createBuiltins } from "../../src/vm/runtime/intrinsics.js"
-import { getOwn, Native, nativeRule, Obj, remove, set } from "../../src/vm/runtime/objects.js"
-import { CodeMode } from "../lib/index.js"
-import { decode, encode } from "../../src/vm/snapshot/codec.js"
-import { Lost, PendingThrow } from "../../src/vm/runtime/model.js"
-import { normalizeError } from "../../src/vm/runtime/errors.js"
+import { parseProgram } from "../src/runtime/execute.js"
+import { Interpreter } from "../src/runtime/interpreter.js"
+import { createBuiltins } from "../src/runtime/intrinsics.js"
+import { getOwn, Native, nativeRule, Obj, remove, set } from "../src/runtime/objects.js"
+import { CodeMode } from "../src/index.js"
+import { decode, encode } from "../src/snapshot/codec.js"
+import { Lost, PendingThrow } from "../src/runtime/model.js"
+import { normalizeError } from "../src/runtime/errors.js"
 import { Effect } from "effect"
-import { ToolRuntime } from "../../src/tool-runtime.js"
-import { nodeId, sourceOf } from "../../src/vm/runtime/source.js"
+import { ToolRuntime } from "../src/tool-runtime.js"
+import { nodeId, sourceOf } from "../src/runtime/source.js"
 
 // Groundwork for suspending and resuming a run: everything the state refers to has a stable name.
 
@@ -281,7 +281,7 @@ describe("heap as data", () => {
 
 describe("prelude", () => {
   test("a run saved and restored while prelude built-ins run continues in their frames", async () => {
-    const child = Bun.spawn(["bun", path.join(import.meta.dir, "../fixtures/prelude-roundtrip.ts")], {
+    const child = Bun.spawn(["bun", path.join(import.meta.dir, "fixtures/prelude-roundtrip.ts")], {
       stdout: "pipe",
       stderr: "inherit",
     })
@@ -320,7 +320,6 @@ describe("lost values", () => {
     unchanged: () => false,
     anchorOf: () => undefined,
     nodeId: () => undefined,
-    astArray: () => undefined,
     lost,
     strict: false,
   })
@@ -328,7 +327,6 @@ describe("lost values", () => {
     named: () => undefined,
     anchor: () => undefined,
     node: () => undefined,
-    astArray: () => undefined,
     interruption: () => {
       throw new Error("no interruption is saved")
     },
diff --git a/packages/codemode/test/vm/run.ts b/packages/codemode/test/run-program.ts
similarity index 54%
rename from packages/codemode/test/vm/run.ts
rename to packages/codemode/test/run-program.ts
index 933358ef328..6277b8d88ca 100644
--- a/packages/codemode/test/vm/run.ts
+++ b/packages/codemode/test/run-program.ts
@@ -1,18 +1,19 @@
 import path from "node:path"
 import { pathToFileURL } from "node:url"
-import { parse, type Program } from "acorn"
-import type { DataValue, Diagnostic, Result } from "../../src/codemode.js"
-import { normalizeError } from "../../src/vm/runtime/errors.js"
-import { createBuiltins } from "../../src/vm/runtime/intrinsics.js"
-import { Interpreter } from "../../src/vm/runtime/interpreter.js"
-import { formatLocation, PendingThrow, sourceLocation } from "../../src/vm/runtime/model.js"
-import type { Value } from "../../src/vm/runtime/objects.js"
-import { Interruption } from "../../src/vm/runtime/signals.js"
-import { Source } from "../../src/vm/runtime/source.js"
-import type { ToolRuntime } from "../../src/tool-runtime.js"
-import type { Snapshot } from "../../src/vm/snapshot/snapshot.js"
+import type { Program } from "acorn"
+import type { DataValue, Diagnostic, Result } from "../src/codemode.js"
+import { normalizeError } from "../src/runtime/errors.js"
+import { parseProgram } from "../src/runtime/execute.js"
+import { createBuiltins } from "../src/runtime/intrinsics.js"
+import { Interpreter } from "../src/runtime/interpreter.js"
+import { PendingThrow } from "../src/runtime/model.js"
+import type { Value } from "../src/runtime/objects.js"
+import { Interruption } from "../src/runtime/signals.js"
+import type { Source } from "../src/runtime/source.js"
+import type { ToolRuntime } from "../src/tool-runtime.js"
+import type { Snapshot } from "../src/snapshot/snapshot.js"
 
-/** A quoted `file:` URL for a module relative to `test/vm`, to import from a script run with `bun -e` on any platform. */
+/** A quoted `file:` URL for a module relative to `test`, to import from a script run with `bun -e` on any platform. */
 export const moduleUrl = (relative: string) =>
   JSON.stringify(pathToFileURL(path.join(import.meta.dir, relative)).href)
 
@@ -36,7 +37,6 @@ export type RunOptions = {
 
 export const parseVmSource = (
   code: string,
-  id = "main",
 ):
   | { readonly ok: true; readonly program: Program; readonly source: Source }
   | { readonly ok: false; readonly error: Diagnostic } => {
@@ -44,38 +44,8 @@ export const parseVmSource = (
     return { ok: false, error: { kind: "ParseError", message: "Code cannot be empty." } }
   }
   try {
-    const program = parse(code, {
-      ecmaVersion: "latest",
-      sourceType: "script",
-      allowReturnOutsideFunction: true,
-      allowAwaitOutsideFunction: true,
-      allowImportExportEverywhere: true,
-      locations: true,
-    })
-    const exported = program.body.find((statement) => statement.type.startsWith("Export"))
-    if (exported) {
-      const location = sourceLocation(exported)
-      return {
-        ok: false,
-        error: {
-          kind: "ParseError",
-          message: `SyntaxError: Exports aren't available. Return the result instead.${formatLocation(location)}`,
-          location,
-        },
-      }
-    }
-    return { ok: true, program, source: new Source(id, code, program) }
+    return parseProgram(code)
   } catch (error) {
-    if (error instanceof SyntaxError && "loc" in error) {
-      const loc = (error as SyntaxError & { readonly loc: { readonly line: number; readonly column: number } }).loc
-      const location = { line: loc.line, column: loc.column + 1 }
-      const reason = error.message.replace(/ \(\d+:\d+\)$/, "")
-      const text = `${reason.endsWith(".") ? reason : `${reason}.`} Code must be plain JavaScript written as a program body.`
-      return {
-        ok: false,
-        error: { kind: "ParseError", message: `SyntaxError: ${text}${formatLocation(location)}`, location },
-      }
-    }
     if (error instanceof RangeError) {
       return { ok: false, error: normalizeError(error) }
     }
@@ -173,49 +143,3 @@ export const runProgram = (code: string, options?: RunOptions): Result => {
     }
   }
 }
-
-const WARMUP_SCRIPT = `
-function fib(n) { return n < 2 ? n : fib(n - 1) + fib(n - 2) }
-let sum = 0
-for (let i = 0; i < 400; i++) sum = (sum + i * 3) % 10007
-const closures = []
-for (let i = 0; i < 16; i++) {
-  let s = "v" + i
-  let o = { x: i, y: s }
-  closures.push(() => o.x + s.length)
-}
-for (const fn of closures) sum += fn()
-const arr = Array.from({ length: 64 }, (_, i) => (i * 17) % 64)
-const mapped = arr.map((x) => x * 2).filter((x) => x % 3 !== 0)
-sum += mapped.reduce((a, b) => a + b, 0)
-const sorted = mapped.slice(0, 32).sort((a, b) => a - b)
-sum += sorted.length + fib(8)
-outer: for (let i = 0; i < 3; i++) {
-  try {
-    for (const x of [1, 2, 3]) {
-      try {
-        if (x === 2) continue
-        if (i === 1 && x === 3) break outer
-        sum += x
-      } finally { sum += 1 }
-    }
-  } catch (e) { sum -= 1 } finally { sum += 2 }
-}
-const { a = 1, b: [c = 2, ...rest] = [3, 4, 5] } = { b: [10, 20, 30] }
-return sum + a + c + rest.length
-`
-
-let warmed = false
-
-/**
- * Startup training program (J3): exercises the VM dispatch loop with diverse types
- * (numbers, strings, objects, arrays, closures, cells, try/catch/finally, iteration, destructuring)
- * so JSC's DFG/FTL tiers up `Vm.prototype.exec` with polymorphic value profiles.
- */
-export const warmupVm = (rounds = 8): void => {
-  if (warmed) return
-  warmed = true
-  for (let i = 0; i < rounds; i++) {
-    runProgram(WARMUP_SCRIPT)
-  }
-}
diff --git a/packages/codemode/test/scan.test.ts b/packages/codemode/test/scan.test.ts
index e4327f019e6..f6a876901b1 100644
--- a/packages/codemode/test/scan.test.ts
+++ b/packages/codemode/test/scan.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, test } from "bun:test"
 import { Effect, Result } from "effect"
-import { CodeMode } from "./lib/index.js"
+import { CodeMode } from "../src/index.js"
 
 describe("CodeMode.scanTools", () => {
   test("extracts dotted, bracketed and nested static tool calls in first-seen order", () => {
diff --git a/packages/codemode/test/set-methods-test262.test.ts b/packages/codemode/test/set-methods-test262.test.ts
index 2aa857ed864..7d94aac1406 100644
--- a/packages/codemode/test/set-methods-test262.test.ts
+++ b/packages/codemode/test/set-methods-test262.test.ts
@@ -71,7 +71,7 @@
  */
 import { describe, expect, test } from "bun:test"
 import { Effect } from "effect"
-import { CodeMode } from "./lib/index.js"
+import { CodeMode } from "../src/index.js"
 
 const value = async (code: string) => {
   const result = await Effect.runPromise(CodeMode.execute({ code, tools: {} }))
diff --git a/packages/codemode/test/signature.test.ts b/packages/codemode/test/signature.test.ts
index 2594ebc160f..ed41e9b02c2 100644
--- a/packages/codemode/test/signature.test.ts
+++ b/packages/codemode/test/signature.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, test } from "bun:test"
 import { Effect, Schema, SchemaGetter } from "effect"
-import { CodeMode, Tool } from "./lib/index.js"
+import { CodeMode, Tool } from "../src/index.js"
 import {
   decodeInput,
   inputProperties,
diff --git a/packages/codemode/test/vm/snapshot.test.ts b/packages/codemode/test/snapshot.test.ts
similarity index 91%
rename from packages/codemode/test/vm/snapshot.test.ts
rename to packages/codemode/test/snapshot.test.ts
index a42e6e247ff..509b9f47e2d 100644
--- a/packages/codemode/test/vm/snapshot.test.ts
+++ b/packages/codemode/test/snapshot.test.ts
@@ -1,14 +1,14 @@
 import { describe, expect, test } from "bun:test"
 import { Effect } from "effect"
-import { CodeMode } from "../../src/index.js"
-import { createBuiltins } from "../../src/vm/runtime/intrinsics.js"
-import { Interpreter } from "../../src/vm/runtime/interpreter.js"
-import { type Snapshot, SnapshotError } from "../../src/vm/snapshot/snapshot.js"
-import { ToolRuntime } from "../../src/tool-runtime.js"
-import { hashOf } from "../../src/vm/code.js"
-import { compileSource } from "../../src/vm/compiler/compile.js"
-import { moduleUrl, parseVmSource, runProgram } from "./run.js"
-import { buildId } from "../../src/vm/snapshot.js"
+import { CodeMode } from "../src/index.js"
+import { createBuiltins } from "../src/runtime/intrinsics.js"
+import { Interpreter } from "../src/runtime/interpreter.js"
+import { type Snapshot, SnapshotError } from "../src/snapshot/snapshot.js"
+import { ToolRuntime } from "../src/tool-runtime.js"
+import { hashOf } from "../src/code.js"
+import { compileSource } from "../src/compiler/compile.js"
+import { moduleUrl, parseVmSource, runProgram } from "./run-program.js"
+import { buildId } from "../src/snapshot.js"
 
 // The VM's snapshots: a run saved and restored into a fresh runtime anywhere it slices goes on as if it never stopped.
 
@@ -268,13 +268,13 @@ describe("determinism", () => {
     const codes = Object.values(programs)
     const local = { hashes: codes.map((code) => hashOf(compileSource(parse(code)))), build: (runtime(), buildId()) }
     const script = `
-      import { hashOf } from ${moduleUrl("../../src/vm/code.js")}
-      import { compileSource } from ${moduleUrl("../../src/vm/compiler/compile.js")}
-      import { parseVmSource } from ${moduleUrl("run.js")}
-      import { buildId } from ${moduleUrl("../../src/vm/snapshot.js")}
-      import { createBuiltins } from ${moduleUrl("../../src/vm/runtime/intrinsics.js")}
-      import { Interpreter } from ${moduleUrl("../../src/vm/runtime/interpreter.js")}
-      import { ToolRuntime } from ${moduleUrl("../../src/tool-runtime.js")}
+      import { hashOf } from ${moduleUrl("../src/code.js")}
+      import { compileSource } from ${moduleUrl("../src/compiler/compile.js")}
+      import { parseVmSource } from ${moduleUrl("run-program.js")}
+      import { buildId } from ${moduleUrl("../src/snapshot.js")}
+      import { createBuiltins } from ${moduleUrl("../src/runtime/intrinsics.js")}
+      import { Interpreter } from ${moduleUrl("../src/runtime/interpreter.js")}
+      import { ToolRuntime } from ${moduleUrl("../src/tool-runtime.js")}
       new Interpreter({ tools: ToolRuntime.make(ToolRuntime.prepare({}), undefined, {}), builtins: createBuiltins() })
       const codes = ${JSON.stringify(codes)}
       console.log(JSON.stringify({ hashes: codes.map((code) => hashOf(compileSource(parseVmSource(code).source))), build: buildId() }))`
diff --git a/packages/codemode/test/vm/state.test.ts b/packages/codemode/test/state.test.ts
similarity index 92%
rename from packages/codemode/test/vm/state.test.ts
rename to packages/codemode/test/state.test.ts
index 16eab1f9636..a085113421b 100644
--- a/packages/codemode/test/vm/state.test.ts
+++ b/packages/codemode/test/state.test.ts
@@ -2,21 +2,21 @@ import { describe, expect, test } from "bun:test"
 import { Glob } from "bun"
 import path from "node:path"
 import { Effect, Schema } from "effect"
-import { CodeMode, Tool } from "../lib/index.js"
-import { parseProgram } from "../../src/vm/runtime/execute.js"
-import { Interpreter } from "../../src/vm/runtime/interpreter.js"
-import { createBuiltins } from "../../src/vm/runtime/intrinsics.js"
-import { GeneratorObj, type Native, nativeRule, Obj, PromiseObj, type Value } from "../../src/vm/runtime/objects.js"
-import { normal } from "../../src/vm/runtime/signals.js"
-import { ToolRuntime } from "../../src/tool-runtime.js"
-import { Code } from "../../src/vm/code.js"
-import { AsyncFromSyncIterator } from "../../src/vm/generators.js"
-import { VmIntrinsic } from "../../src/vm/internal-prelude.js"
-import { Cell, CodeFlags } from "../../src/vm/opcodes.js"
-import type { Stop } from "../../src/vm/scheduler.js"
-import { CustomIter, Frame, Mode, Vm } from "../../src/vm/vm.js"
+import { CodeMode, Tool } from "../src/index.js"
+import { parseProgram } from "../src/runtime/execute.js"
+import { Interpreter } from "../src/runtime/interpreter.js"
+import { createBuiltins } from "../src/runtime/intrinsics.js"
+import { GeneratorObj, type Native, nativeRule, Obj, PromiseObj, type Value } from "../src/runtime/objects.js"
+import { normal } from "../src/runtime/signals.js"
+import { ToolRuntime } from "../src/tool-runtime.js"
+import { Code } from "../src/code.js"
+import { AsyncFromSyncIterator } from "../src/generators.js"
+import { VmIntrinsic } from "../src/internal-prelude.js"
+import { Cell, CodeFlags } from "../src/opcodes.js"
+import type { Stop } from "../src/scheduler.js"
+import { CustomIter, Frame, Mode, Vm } from "../src/vm.js"
 
-// The VM (`src/vm`) runs programs as bytecode frames, and keeps the jobs, promises, and host calls they wait on as
+// The VM (`src/vm.ts`) runs programs as bytecode frames, and keeps the jobs, promises, and host calls they wait on as
 // data: a frame is its code, pc, and registers, and every suspension point is one. The Effect driver only does what
 // the VM's stops ask.
 
@@ -218,6 +218,7 @@ describe("vm", () => {
     expect(next).toEqual({ kind: "done", completion: normal(2450) })
   })
 
+  // Sorting 300,000 strings (to cross multiple 65,536-item merge steps) with tripEvery = 1 takes ~7s on Windows CI.
   test("a large default sort runs in bounded native steps, and sorts as JS does", () => {
     const words = Array.from({ length: 300_000 }, (_, i) => ((i * 7919) % 300_007).toString(36))
     const vm = vmFor(`
@@ -246,7 +247,7 @@ describe("vm", () => {
         9100 in sorted,
       ]),
     })
-  })
+  }, 15_000)
 
   test("concurrent tool calls stop the VM once, with every call in one batch", () => {
     const vm = vmFor(`return await Promise.all([1, 2, 3].map((value) => tools.echo({ value })))`)
@@ -383,11 +384,24 @@ describe("vm", () => {
   })
 
   test("the VM does not import Effect", async () => {
-    const root = path.join(import.meta.dir, "../..")
+    const root = path.join(import.meta.dir, "..")
+    const host = new Set([
+      "src/codemode.ts",
+      "src/extension.ts",
+      "src/scan.ts",
+      "src/tool-error.ts",
+      "src/tool-runtime.ts",
+      "src/tool-schema.ts",
+      "src/tool.ts",
+      "src/runtime/driver.ts",
+      "src/runtime/execute.ts",
+      "src/runtime/extensions.ts",
+      "src/runtime/signals.ts",
+    ])
     // Glob paths use the platform's separator.
-    const files = (await Array.fromAsync(new Glob("src/vm/**/*.ts").scan({ cwd: root }))).filter(
-      (file) => !file.split(path.sep).join("/").startsWith("src/vm/runtime/"),
-    )
+    const files = (await Array.fromAsync(new Glob("src/**/*.ts").scan({ cwd: root })))
+      .map((file) => file.split(path.sep).join("/"))
+      .filter((file) => !file.startsWith("src/openapi/") && !host.has(file))
     expect(files.length).toBeGreaterThan(0)
     for (const file of files) {
       expect(await Bun.file(path.join(root, file)).text()).not.toMatch(/from "effect"/)
diff --git a/packages/codemode/test/stdlib.test.ts b/packages/codemode/test/stdlib.test.ts
index 9212fe34a04..9c0d01672cc 100644
--- a/packages/codemode/test/stdlib.test.ts
+++ b/packages/codemode/test/stdlib.test.ts
@@ -16,7 +16,7 @@
  */
 import { describe, expect, test } from "bun:test"
 import { Effect, Schema } from "effect"
-import { CodeMode, Tool } from "./lib/index.js"
+import { CodeMode, Tool } from "../src/index.js"
 
 // Standard-library value types: Date, RegExp, Map, Set. Programs use them as ordinary JS;
 // intra-CodeMode checkpoints (Object.* helpers, spread, coercion inputs) preserve the live
diff --git a/packages/codemode/test/string-core-test262.test.ts b/packages/codemode/test/string-core-test262.test.ts
index 30400130715..9173fe352da 100644
--- a/packages/codemode/test/string-core-test262.test.ts
+++ b/packages/codemode/test/string-core-test262.test.ts
@@ -151,7 +151,7 @@
  */
 import { describe, expect, test } from "bun:test"
 import { Effect } from "effect"
-import { CodeMode } from "./lib/index.js"
+import { CodeMode } from "../src/index.js"
 
 type Argument = string | number | undefined
 type Outcome = "undefined" | "length" | "RangeError"
diff --git a/packages/codemode/test/string-date-methods-test262.test.ts b/packages/codemode/test/string-date-methods-test262.test.ts
index 24a5013c8ec..41757052756 100644
--- a/packages/codemode/test/string-date-methods-test262.test.ts
+++ b/packages/codemode/test/string-date-methods-test262.test.ts
@@ -24,7 +24,7 @@
  */
 import { describe, expect, test } from "bun:test"
 import { Effect } from "effect"
-import { CodeMode } from "./lib/index.js"
+import { CodeMode } from "../src/index.js"
 
 const value = async (code: string) => {
   const result = await Effect.runPromise(CodeMode.execute({ code, tools: {} }))
diff --git a/packages/codemode/test/string-regexp-test262.test.ts b/packages/codemode/test/string-regexp-test262.test.ts
index 513de982739..fa0d6f709d6 100644
--- a/packages/codemode/test/string-regexp-test262.test.ts
+++ b/packages/codemode/test/string-regexp-test262.test.ts
@@ -82,7 +82,7 @@
  */
 import { describe, expect, test } from "bun:test"
 import { Effect } from "effect"
-import { CodeMode } from "./lib/index.js"
+import { CodeMode } from "../src/index.js"
 
 type Vector = {
   readonly path: string
diff --git a/packages/codemode/test/string-search-test262.test.ts b/packages/codemode/test/string-search-test262.test.ts
index 6abf045fe71..b596fc7bf9a 100644
--- a/packages/codemode/test/string-search-test262.test.ts
+++ b/packages/codemode/test/string-search-test262.test.ts
@@ -102,7 +102,7 @@
  */
 import { describe, expect, test } from "bun:test"
 import { Effect } from "effect"
-import { CodeMode } from "./lib/index.js"
+import { CodeMode } from "../src/index.js"
 
 const value = async (code: string) => {
   const result = await Effect.runPromise(CodeMode.execute({ code, tools: {} }))
diff --git a/packages/codemode/test/vm/suspend.test.ts b/packages/codemode/test/suspend.test.ts
similarity index 99%
rename from packages/codemode/test/vm/suspend.test.ts
rename to packages/codemode/test/suspend.test.ts
index e43c17a0526..7471f9b55d6 100644
--- a/packages/codemode/test/vm/suspend.test.ts
+++ b/packages/codemode/test/suspend.test.ts
@@ -2,7 +2,7 @@ import { describe, expect, test } from "bun:test"
 import { tmpdir } from "node:os"
 import path from "node:path"
 import { Context, Effect, Fiber, Schema } from "effect"
-import { CodeMode, Extension, Tool } from "../../src/index.js"
+import { CodeMode, Extension, Tool } from "../src/index.js"
 
 // Suspending a run, saving its state, and resuming it in a brand-new runtime.
 
@@ -450,7 +450,7 @@ describe("suspend", () => {
 
   test("the snapshot codec does not import Effect", async () => {
     for (const file of ["codec.ts", "snapshot.ts"]) {
-      expect(await Bun.file(path.join(import.meta.dir, "../../src/vm/snapshot", file)).text()).not.toMatch(
+      expect(await Bun.file(path.join(import.meta.dir, "../src/snapshot", file)).text()).not.toMatch(
         /from "effect"/,
       )
     }
@@ -479,7 +479,7 @@ describe("resume", () => {
     const file = path.join(tmpdir(), `codemode-${crypto.randomUUID()}.state`)
     await Bun.write(file, CodeMode.toBytes(suspended.state))
     try {
-      const child = Bun.spawn(["bun", path.join(import.meta.dir, "../fixtures/resume-process.ts"), file], {
+      const child = Bun.spawn(["bun", path.join(import.meta.dir, "fixtures/resume-process.ts"), file], {
         stdout: "pipe",
         stderr: "inherit",
       })
diff --git a/packages/codemode/test/test262/run.ts b/packages/codemode/test/test262/run.ts
index 0775e76517b..1f8dd8d91ec 100644
--- a/packages/codemode/test/test262/run.ts
+++ b/packages/codemode/test/test262/run.ts
@@ -1,15 +1,15 @@
-// Runs one vendored test262 file verbatim on the bytecode VM. The harness (assert, Test262Error, compareArray, $DONE,
+// Runs one vendored test262 file verbatim. The harness (assert, Test262Error, compareArray, $DONE,
 // $DONOTEVALUATE) is host-provided, except `assert` itself: a program function made by the prelude, so that
 // `assert.throws` can call the function it tests and catch what it throws as plain program code. Its checks and
 // failure messages are the host's (`$assert`).
 import path from "node:path"
 import { Effect } from "effect"
-import { executeProgram } from "../../src/vm/runtime/execute.js"
-import type { Interpreter } from "../../src/vm/runtime/interpreter.js"
-import { Throw } from "../../src/vm/runtime/model.js"
-import { createErrorValue } from "../../src/vm/runtime/intrinsics.js"
-import { constructor, fn, methods } from "../../src/vm/runtime/native.js"
-import { Callable, define, get, hidden, Arr, Fn, Obj, type Value } from "../../src/vm/runtime/objects.js"
+import { finishExecution, startProgram } from "../../src/runtime/execute.js"
+import type { Interpreter } from "../../src/runtime/interpreter.js"
+import { Throw } from "../../src/runtime/model.js"
+import { createErrorValue } from "../../src/runtime/intrinsics.js"
+import { constructor, fn, methods } from "../../src/runtime/native.js"
+import { Callable, define, get, hidden, Arr, Fn, Obj, type Value } from "../../src/runtime/objects.js"
 import { ToolRuntime } from "../../src/tool-runtime.js"
 
 export const root = import.meta.dir
@@ -29,8 +29,11 @@ type Frontmatter = {
   negative?: { phase: "parse" | "resolution" | "runtime"; type: string }
 }
 
-const limits = { timeoutMs: 5000, maxToolCalls: undefined, maxOutputBytes: undefined }
-const prepared = ToolRuntime.prepare<never>({})
+const setup = {
+  prepared: ToolRuntime.prepare<never>({}),
+  limits: { timeoutMs: 5000, maxToolCalls: undefined, maxOutputBytes: undefined },
+  hooks: {},
+}
 
 // One line, on the line of the "use strict" directive, so the test's own line numbers stay as they are.
 const prelude = [
@@ -52,10 +55,17 @@ export const run = async (file: string): Promise<Outcome> => {
   // work instead, so drain explicitly.
   const drain = meta.flags?.includes("async") ? "\nfor (let i = 0; i < 100; i++) await null" : ""
   const result = await Effect.runPromise(
-    executeProgram(`"use strict"; ${prelude}\n${source}${drain}`, prepared, limits, {}, (ctx) =>
-      harness(ctx, (error) => {
-        done ??= { error }
-      }),
+    finishExecution(
+      startProgram(
+        {
+          ...setup,
+          globals: (ctx) =>
+            harness(ctx, (error) => {
+              done ??= { error }
+            }),
+        },
+        `"use strict"; ${prelude}\n${source}${drain}`,
+      ).run(),
     ),
   )
   if (meta.negative !== undefined) {
diff --git a/packages/codemode/test/tool-paths.test.ts b/packages/codemode/test/tool-paths.test.ts
index 76c4a875c44..a739d651510 100644
--- a/packages/codemode/test/tool-paths.test.ts
+++ b/packages/codemode/test/tool-paths.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, test } from "bun:test"
 import { Effect, Schema } from "effect"
-import { CodeMode, Namespace, Tool } from "./lib/index.js"
+import { CodeMode, Namespace, Tool } from "../src/index.js"
 
 const echo = (description: string, result: string) =>
   Tool.make({
diff --git a/packages/codemode/test/var-hoisting-test262.test.ts b/packages/codemode/test/var-hoisting-test262.test.ts
index a1729841f49..667603f5232 100644
--- a/packages/codemode/test/var-hoisting-test262.test.ts
+++ b/packages/codemode/test/var-hoisting-test262.test.ts
@@ -21,7 +21,7 @@
  */
 import { describe, expect, test } from "bun:test"
 import { Effect } from "effect"
-import { CodeMode } from "./lib/index.js"
+import { CodeMode } from "../src/index.js"
 
 const value = async (code: string) => {
   const result = await Effect.runPromise(CodeMode.execute({ code, tools: {} }))
diff --git a/packages/codemode/test/vm/verify.ts b/packages/codemode/test/verify-bytecode.ts
similarity index 99%
rename from packages/codemode/test/vm/verify.ts
rename to packages/codemode/test/verify-bytecode.ts
index 0dce361a801..9babd65dbc4 100644
--- a/packages/codemode/test/vm/verify.ts
+++ b/packages/codemode/test/verify-bytecode.ts
@@ -1,5 +1,5 @@
-import type { Code } from "../../src/vm/code.js"
-import { CheckBaseKind, CondKind, ImportKind, Op, OpNames } from "../../src/vm/opcodes.js"
+import type { Code } from "../src/code.js"
+import { CheckBaseKind, CondKind, ImportKind, Op, OpNames } from "../src/opcodes.js"
 
 /**
  * Stack-depth verifier (C5): runs abstract interpretation over packed bytecode independent of `CodeBuilder`,
diff --git a/packages/codemode/test/vm/vm.test.ts b/packages/codemode/test/vm.test.ts
similarity index 98%
rename from packages/codemode/test/vm/vm.test.ts
rename to packages/codemode/test/vm.test.ts
index 5570bab289c..b33c1cfb2c9 100644
--- a/packages/codemode/test/vm/vm.test.ts
+++ b/packages/codemode/test/vm.test.ts
@@ -1,9 +1,9 @@
 import { describe, expect, test } from "bun:test"
-import { disassembleSource } from "../../script/disasm.js"
-import { hashOf } from "../../src/vm/code.js"
-import { compileSource } from "../../src/vm/compiler/compile.js"
-import { verifyAll } from "./verify.js"
-import { parseVmSource, runProgram, warmupVm } from "./run.js"
+import { disassembleSource } from "../script/disasm.js"
+import { hashOf } from "../src/code.js"
+import { compileSource } from "../src/compiler/compile.js"
+import { verifyAll } from "./verify-bytecode.js"
+import { parseVmSource, runProgram } from "./run-program.js"
 
 const val = (code: string) => {
   const parsed = parseVmSource(code)
@@ -496,7 +496,6 @@ describe("generators, async functions, async generators, yield*, and for-await",
 
 describe("built-ins, prelude, and coercion", () => {
   test("array callbacks, sort, Map/Set, Object.groupBy, JSON reviver/replacer, and ToPrimitive", () => {
-    warmupVm(2)
     expect(
       val(`
         const arr = Array.from({ length: 6 }, (_, i) => i + 1)
diff --git a/packages/codemode/test/web-wpt.test.ts b/packages/codemode/test/web-wpt.test.ts
index dc9e1a64d9a..05e51d06457 100644
--- a/packages/codemode/test/web-wpt.test.ts
+++ b/packages/codemode/test/web-wpt.test.ts
@@ -13,7 +13,7 @@
  */
 import { describe, expect, test } from "bun:test"
 import { Effect } from "effect"
-import { CodeMode } from "./lib/index.js"
+import { CodeMode } from "../src/index.js"
 
 const base64Cases = (await Bun.file(new URL("./fixtures/wpt-base64.json", import.meta.url)).json()) as Array<
   [string, Array<number> | null]