11 files changed, 323 insertions, 259 deletions

diff --git a/cli/js/compiler.ts b/cli/js/compiler.ts
index 394c6cf52..f003d7d0b 100644
--- a/cli/js/compiler.ts
+++ b/cli/js/compiler.ts
@@ -304,7 +304,7 @@ async function tsCompilerOnMessage({
   }
 
   // The compiler isolate exits after a single message.
-  globalThis.workerClose();
+  globalThis.close();
 }
 
 async function wasmCompilerOnMessage({
@@ -332,7 +332,7 @@ async function wasmCompilerOnMessage({
   util.log("<<< WASM compile end");
 
   // The compiler isolate exits after a single message.
-  globalThis.workerClose();
+  globalThis.close();
 }
 
 function bootstrapTsCompilerRuntime(): void {
diff --git a/cli/js/compiler_bootstrap.ts b/cli/js/compiler_bootstrap.ts
index afb3d2be5..585aec016 100644
--- a/cli/js/compiler_bootstrap.ts
+++ b/cli/js/compiler_bootstrap.ts
@@ -15,17 +15,27 @@ const options = host.getCompilationSettings();
 // This is a hacky way of adding our libs to the libs available in TypeScript()
 // as these are internal APIs of TypeScript which maintain valid libs
 /* eslint-disable @typescript-eslint/no-explicit-any */
-(ts as any).libs.push("deno_main", "deno_worker", "deno");
-(ts as any).libMap.set("deno_main", "lib.deno_main.d.ts");
-(ts as any).libMap.set("deno_worker", "lib.deno_worker.d.ts");
-(ts as any).libMap.set("deno", "lib.deno.d.ts");
+(ts as any).libs.push(
+  "deno_ns",
+  "deno_window",
+  "deno_worker",
+  "deno_shared_globals"
+);
+(ts as any).libMap.set("deno_ns", "lib.deno.ns.d.ts");
+(ts as any).libMap.set("deno_window", "lib.deno.window.d.ts");
+(ts as any).libMap.set("deno_worker", "lib.deno.worker.d.ts");
+(ts as any).libMap.set("deno_shared_globals", "lib.deno.shared_globals.d.ts");
 /* eslint-enable @typescript-eslint/no-explicit-any */
 
 // this pre-populates the cache at snapshot time of our library files, so they
 // are available in the future when needed.
-host.getSourceFile(`${ASSETS}/lib.deno_main.d.ts`, ts.ScriptTarget.ESNext);
-host.getSourceFile(`${ASSETS}/lib.deno_worker.d.ts`, ts.ScriptTarget.ESNext);
-host.getSourceFile(`${ASSETS}/lib.deno.d.ts`, ts.ScriptTarget.ESNext);
+host.getSourceFile(`${ASSETS}/lib.deno.ns.d.ts`, ts.ScriptTarget.ESNext);
+host.getSourceFile(`${ASSETS}/lib.deno.window.d.ts`, ts.ScriptTarget.ESNext);
+host.getSourceFile(`${ASSETS}/lib.deno.worker.d.ts`, ts.ScriptTarget.ESNext);
+host.getSourceFile(
+  `${ASSETS}/lib.deno.shared_globals.d.ts`,
+  ts.ScriptTarget.ESNext
+);
 
 /**
  * This function spins up TS compiler and loads all available libraries
diff --git a/cli/js/compiler_host.ts b/cli/js/compiler_host.ts
index 619ce702a..291f6fbc5 100644
--- a/cli/js/compiler_host.ts
+++ b/cli/js/compiler_host.ts
@@ -233,9 +233,9 @@ export class Host implements ts.CompilerHost {
     switch (this._target) {
       case CompilerHostTarget.Main:
       case CompilerHostTarget.Runtime:
-        return `${ASSETS}/lib.deno_main.d.ts`;
+        return `${ASSETS}/lib.deno.window.d.ts`;
       case CompilerHostTarget.Worker:
-        return `${ASSETS}/lib.deno_worker.d.ts`;
+        return `${ASSETS}/lib.deno.worker.d.ts`;
     }
   }
 
diff --git a/cli/js/globals.ts b/cli/js/globals.ts
index e6c1e855c..7cce739d5 100644
--- a/cli/js/globals.ts
+++ b/cli/js/globals.ts
@@ -132,7 +132,7 @@ declare global {
   // eslint-disable-next-line @typescript-eslint/no-explicit-any
   var onmessage: ((e: { data: any }) => Promise<void> | void) | undefined;
   // Called in compiler
-  var workerClose: () => void;
+  var close: () => void;
   // eslint-disable-next-line @typescript-eslint/no-explicit-any
   var postMessage: (msg: any) => void;
   // Assigned to `self` global - compiler
diff --git a/cli/js/lib.deno.d.ts b/cli/js/lib.deno.ns.d.ts
index 0fa6f008c..0fa6f008c 100644
--- a/cli/js/lib.deno.d.ts
+++ b/cli/js/lib.deno.ns.d.ts
diff --git a/cli/js/lib.deno_main.d.ts b/cli/js/lib.deno.shared_globals.d.ts
index 52b6fb7f5..c8dfc833d 100644
--- a/cli/js/lib.deno_main.d.ts
+++ b/cli/js/lib.deno.shared_globals.d.ts
@@ -3,23 +3,23 @@
 /* eslint-disable @typescript-eslint/no-unused-vars, @typescript-eslint/no-empty-interface, @typescript-eslint/no-explicit-any */
 
 /// <reference no-default-lib="true" />
-/// <reference lib="deno" />
+/// <reference lib="deno_ns" />
 /// <reference lib="esnext" />
 
-declare interface Window {
-  window: Window & typeof globalThis;
+// https://developer.mozilla.org/en-US/docs/Web/API/WindowOrWorkerGlobalScope
+
+declare interface WindowOrWorkerGlobalScope {
+  // methods
   atob: typeof __textEncoding.atob;
   btoa: typeof __textEncoding.btoa;
-  fetch: typeof __fetch.fetch;
-  clearTimeout: typeof __timers.clearTimeout;
   clearInterval: typeof __timers.clearInterval;
-  console: __console.Console;
-  setTimeout: typeof __timers.setTimeout;
+  clearTimeout: typeof __timers.clearTimeout;
+  fetch: typeof __fetch.fetch;
+  queueMicrotask: (task: () => void) => void;
   setInterval: typeof __timers.setInterval;
-  location: __domTypes.Location;
-  onload: Function | undefined;
-  onunload: Function | undefined;
-  crypto: Crypto;
+  setTimeout: typeof __timers.setTimeout;
+  // properties
+  console: __console.Console;
   Blob: typeof __blob.DenoBlob;
   File: __domTypes.DomFileConstructor;
   CustomEvent: typeof __customEvent.CustomEvent;
@@ -34,11 +34,9 @@ declare interface Window {
   Request: __domTypes.RequestConstructor;
   Response: typeof __fetch.Response;
   performance: __performanceUtil.Performance;
-  onmessage: (e: { data: any }) => void;
-  onerror: undefined | typeof onerror;
-  workerClose: typeof __workerMain.workerClose;
-  postMessage: typeof __workerMain.postMessage;
   Worker: typeof __workers.WorkerImpl;
+  location: __domTypes.Location;
+
   addEventListener: (
     type: string,
     callback: (event: __domTypes.Event) => void | null,
@@ -50,23 +48,17 @@ declare interface Window {
     callback: (event: __domTypes.Event) => void | null,
     options?: boolean | __domTypes.EventListenerOptions | undefined
   ) => void;
-  queueMicrotask: (task: () => void) => void;
-  Deno: typeof Deno;
 }
 
-declare const window: Window & typeof globalThis;
 declare const atob: typeof __textEncoding.atob;
 declare const btoa: typeof __textEncoding.btoa;
-declare const fetch: typeof __fetch.fetch;
-declare const clearTimeout: typeof __timers.clearTimeout;
 declare const clearInterval: typeof __timers.clearInterval;
-declare const console: __console.Console;
-declare const setTimeout: typeof __timers.setTimeout;
+declare const clearTimeout: typeof __timers.clearTimeout;
+declare const fetch: typeof __fetch.fetch;
 declare const setInterval: typeof __timers.setInterval;
-declare const location: __domTypes.Location;
-declare const onload: Function | undefined;
-declare const onunload: Function | undefined;
-declare const crypto: Crypto;
+declare const setTimeout: typeof __timers.setTimeout;
+
+declare const console: __console.Console;
 declare const Blob: typeof __blob.DenoBlob;
 declare const File: __domTypes.DomFileConstructor;
 declare const CustomEventInit: typeof __customEvent.CustomEventInit;
@@ -78,25 +70,15 @@ declare const EventTarget: typeof __eventTarget.EventTarget;
 declare const URL: typeof __url.URL;
 declare const URLSearchParams: typeof __urlSearchParams.URLSearchParams;
 declare const Headers: __domTypes.HeadersConstructor;
+declare const location: __domTypes.Location;
 declare const FormData: __domTypes.FormDataConstructor;
 declare const TextEncoder: typeof __textEncoding.TextEncoder;
 declare const TextDecoder: typeof __textEncoding.TextDecoder;
 declare const Request: __domTypes.RequestConstructor;
 declare const Response: typeof __fetch.Response;
 declare const performance: __performanceUtil.Performance;
-declare let onmessage: ((e: { data: any }) => Promise<void> | void) | undefined;
-declare let onerror:
-  | ((
-      msg: string,
-      source: string,
-      lineno: number,
-      colno: number,
-      e: Event
-    ) => boolean | void)
-  | undefined;
-declare const workerClose: typeof __workerMain.workerClose;
-declare const postMessage: typeof __workerMain.postMessage;
 declare const Worker: typeof __workers.WorkerImpl;
+
 declare const addEventListener: (
   type: string,
   callback: (event: __domTypes.Event) => void | null,
@@ -133,198 +115,6 @@ declare interface ImportMeta {
   main: boolean;
 }
 
-declare interface Crypto {
-  readonly subtle: null;
-  getRandomValues<
-    T extends
-      | Int8Array
-      | Int16Array
-      | Int32Array
-      | Uint8Array
-      | Uint16Array
-      | Uint32Array
-      | Uint8ClampedArray
-      | Float32Array
-      | Float64Array
-      | DataView
-      | null
-  >(
-    array: T
-  ): T;
-}
-
-// This follows the WebIDL at: https://webassembly.github.io/spec/js-api/
-// and: https://webassembly.github.io/spec/web-api/
-
-declare namespace WebAssembly {
-  interface WebAssemblyInstantiatedSource {
-    module: Module;
-    instance: Instance;
-  }
-
-  /** Compiles a `WebAssembly.Module` from WebAssembly binary code.  This
-   * function is useful if it is necessary to a compile a module before it can
-   * be instantiated (otherwise, the `WebAssembly.instantiate()` function
-   * should be used). */
-  function compile(bufferSource: __domTypes.BufferSource): Promise<Module>;
-
-  /** Compiles a `WebAssembly.Module` directly from a streamed underlying
-   * source. This function is useful if it is necessary to a compile a module
-   * before it can be instantiated (otherwise, the
-   * `WebAssembly.instantiateStreaming()` function should be used). */
-  function compileStreaming(
-    source: Promise<__domTypes.Response>
-  ): Promise<Module>;
-
-  /** Takes the WebAssembly binary code, in the form of a typed array or
-   * `ArrayBuffer`, and performs both compilation and instantiation in one step.
-   * The returned `Promise` resolves to both a compiled `WebAssembly.Module` and
-   * its first `WebAssembly.Instance`. */
-  function instantiate(
-    bufferSource: __domTypes.BufferSource,
-    importObject?: object
-  ): Promise<WebAssemblyInstantiatedSource>;
-
-  /** Takes an already-compiled `WebAssembly.Module` and returns a `Promise`
-   * that resolves to an `Instance` of that `Module`. This overload is useful if
-   * the `Module` has already been compiled. */
-  function instantiate(
-    module: Module,
-    importObject?: object
-  ): Promise<Instance>;
-
-  /** Compiles and instantiates a WebAssembly module directly from a streamed
-   * underlying source. This is the most efficient, optimized way to load wasm
-   * code. */
-  function instantiateStreaming(
-    source: Promise<__domTypes.Response>,
-    importObject?: object
-  ): Promise<WebAssemblyInstantiatedSource>;
-
-  /** Validates a given typed array of WebAssembly binary code, returning
-   * whether the bytes form a valid wasm module (`true`) or not (`false`). */
-  function validate(bufferSource: __domTypes.BufferSource): boolean;
-
-  type ImportExportKind = "function" | "table" | "memory" | "global";
-
-  interface ModuleExportDescriptor {
-    name: string;
-    kind: ImportExportKind;
-  }
-  interface ModuleImportDescriptor {
-    module: string;
-    name: string;
-    kind: ImportExportKind;
-  }
-
-  class Module {
-    constructor(bufferSource: __domTypes.BufferSource);
-
-    /** Given a `Module` and string, returns a copy of the contents of all
-     * custom sections in the module with the given string name. */
-    static customSections(
-      moduleObject: Module,
-      sectionName: string
-    ): ArrayBuffer;
-
-    /** Given a `Module`, returns an array containing descriptions of all the
-     * declared exports. */
-    static exports(moduleObject: Module): ModuleExportDescriptor[];
-
-    /** Given a `Module`, returns an array containing descriptions of all the
-     * declared imports. */
-    static imports(moduleObject: Module): ModuleImportDescriptor[];
-  }
-
-  class Instance<T extends object = { [key: string]: any }> {
-    constructor(module: Module, importObject?: object);
-
-    /** An object containing as its members all the functions exported from the
-     * WebAssembly module instance, to allow them to be accessed and used by
-     * JavaScript. */
-    readonly exports: T;
-  }
-
-  interface MemoryDescriptor {
-    initial: number;
-    maximum?: number;
-  }
-
-  class Memory {
-    constructor(descriptor: MemoryDescriptor);
-
-    /** An accessor property that returns the buffer contained in the memory. */
-    readonly buffer: ArrayBuffer;
-
-    /** Increases the size of the memory instance by a specified number of
-     * WebAssembly pages (each one is 64KB in size). */
-    grow(delta: number): number;
-  }
-
-  type TableKind = "anyfunc";
-
-  interface TableDescriptor {
-    element: TableKind;
-    initial: number;
-    maximum?: number;
-  }
-
-  class Table {
-    constructor(descriptor: TableDescriptor);
-
-    /** Returns the length of the table, i.e. the number of elements. */
-    readonly length: number;
-
-    /** Accessor function — gets the element stored at a given index. */
-    get(index: number): (...args: any[]) => any;
-
-    /** Increases the size of the Table instance by a specified number of
-     * elements. */
-    grow(delta: number): number;
-
-    /** Sets an element stored at a given index to a given value. */
-    set(index: number, value: (...args: any[]) => any): void;
-  }
-
-  type ValueType = "i32" | "i64" | "f32" | "f64";
-
-  interface GlobalDescriptor {
-    value: ValueType;
-    mutable?: boolean;
-  }
-
-  /** Represents a global variable instance, accessible from both JavaScript and
-   * importable/exportable across one or more `WebAssembly.Module` instances.
-   * This allows dynamic linking of multiple modules. */
-  class Global {
-    constructor(descriptor: GlobalDescriptor, value?: any);
-
-    /** Old-style method that returns the value contained inside the global
-     * variable. */
-    valueOf(): any;
-
-    /** The value contained inside the global variable — this can be used to
-     * directly set and get the global's value. */
-    value: any;
-  }
-
-  /** Indicates an error during WebAssembly decoding or validation */
-  class CompileError extends Error {
-    constructor(message: string, fileName?: string, lineNumber?: string);
-  }
-
-  /** Indicates an error during module instantiation (besides traps from the
-   * start function). */
-  class LinkError extends Error {
-    constructor(message: string, fileName?: string, lineNumber?: string);
-  }
-
-  /** Is thrown whenever WebAssembly specifies a trap. */
-  class RuntimeError extends Error {
-    constructor(message: string, fileName?: string, lineNumber?: string);
-  }
-}
-
 declare namespace __domTypes {
   // @url js/dom_types.d.ts
 
@@ -1519,13 +1309,6 @@ declare namespace __url {
   };
 }
 
-declare namespace __workerMain {
-  export let onmessage: (e: { data: any }) => void;
-  export function postMessage(data: any): void;
-  export function getMessage(): Promise<any>;
-  export function workerClose(): void;
-}
-
 declare namespace __workers {
   // @url js/workers.d.ts
   export interface Worker {
@@ -1533,9 +1316,11 @@ declare namespace __workers {
     onmessage?: (e: { data: any }) => void;
     onmessageerror?: () => void;
     postMessage(data: any): void;
+    terminate(): void;
   }
   export interface WorkerOptions {
     type?: "classic" | "module";
+    name?: string;
   }
   export class WorkerImpl implements Worker {
     private readonly id;
@@ -1546,6 +1331,7 @@ declare namespace __workers {
     onmessageerror?: () => void;
     constructor(specifier: string, options?: WorkerOptions);
     postMessage(data: any): void;
+    terminate(): void;
     private run;
   }
 }
diff --git a/cli/js/lib.deno.window.d.ts b/cli/js/lib.deno.window.d.ts
new file mode 100644
index 000000000..d4dc08acb
--- /dev/null
+++ b/cli/js/lib.deno.window.d.ts
@@ -0,0 +1,214 @@
+// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
+
+/* eslint-disable @typescript-eslint/no-unused-vars, @typescript-eslint/no-empty-interface, @typescript-eslint/no-explicit-any */
+
+/// <reference no-default-lib="true" />
+/// <reference lib="deno_ns" />
+/// <reference lib="deno_shared_globals" />
+/// <reference lib="esnext" />
+
+declare interface Window extends WindowOrWorkerGlobalScope {
+  window: Window & WindowOrWorkerGlobalScope & typeof globalThis;
+  onload: Function | undefined;
+  onunload: Function | undefined;
+  crypto: Crypto;
+  Deno: typeof Deno;
+}
+
+declare const window: Window & WindowOrWorkerGlobalScope & typeof globalThis;
+declare const onload: Function | undefined;
+declare const onunload: Function | undefined;
+declare const crypto: Crypto;
+
+declare interface Crypto {
+  readonly subtle: null;
+  getRandomValues<
+    T extends
+      | Int8Array
+      | Int16Array
+      | Int32Array
+      | Uint8Array
+      | Uint16Array
+      | Uint32Array
+      | Uint8ClampedArray
+      | Float32Array
+      | Float64Array
+      | DataView
+      | null
+  >(
+    array: T
+  ): T;
+}
+
+// This follows the WebIDL at: https://webassembly.github.io/spec/js-api/
+// and: https://webassembly.github.io/spec/web-api/
+
+declare namespace WebAssembly {
+  interface WebAssemblyInstantiatedSource {
+    module: Module;
+    instance: Instance;
+  }
+
+  /** Compiles a `WebAssembly.Module` from WebAssembly binary code.  This
+   * function is useful if it is necessary to a compile a module before it can
+   * be instantiated (otherwise, the `WebAssembly.instantiate()` function
+   * should be used). */
+  function compile(bufferSource: __domTypes.BufferSource): Promise<Module>;
+
+  /** Compiles a `WebAssembly.Module` directly from a streamed underlying
+   * source. This function is useful if it is necessary to a compile a module
+   * before it can be instantiated (otherwise, the
+   * `WebAssembly.instantiateStreaming()` function should be used). */
+  function compileStreaming(
+    source: Promise<__domTypes.Response>
+  ): Promise<Module>;
+
+  /** Takes the WebAssembly binary code, in the form of a typed array or
+   * `ArrayBuffer`, and performs both compilation and instantiation in one step.
+   * The returned `Promise` resolves to both a compiled `WebAssembly.Module` and
+   * its first `WebAssembly.Instance`. */
+  function instantiate(
+    bufferSource: __domTypes.BufferSource,
+    importObject?: object
+  ): Promise<WebAssemblyInstantiatedSource>;
+
+  /** Takes an already-compiled `WebAssembly.Module` and returns a `Promise`
+   * that resolves to an `Instance` of that `Module`. This overload is useful if
+   * the `Module` has already been compiled. */
+  function instantiate(
+    module: Module,
+    importObject?: object
+  ): Promise<Instance>;
+
+  /** Compiles and instantiates a WebAssembly module directly from a streamed
+   * underlying source. This is the most efficient, optimized way to load wasm
+   * code. */
+  function instantiateStreaming(
+    source: Promise<__domTypes.Response>,
+    importObject?: object
+  ): Promise<WebAssemblyInstantiatedSource>;
+
+  /** Validates a given typed array of WebAssembly binary code, returning
+   * whether the bytes form a valid wasm module (`true`) or not (`false`). */
+  function validate(bufferSource: __domTypes.BufferSource): boolean;
+
+  type ImportExportKind = "function" | "table" | "memory" | "global";
+
+  interface ModuleExportDescriptor {
+    name: string;
+    kind: ImportExportKind;
+  }
+  interface ModuleImportDescriptor {
+    module: string;
+    name: string;
+    kind: ImportExportKind;
+  }
+
+  class Module {
+    constructor(bufferSource: __domTypes.BufferSource);
+
+    /** Given a `Module` and string, returns a copy of the contents of all
+     * custom sections in the module with the given string name. */
+    static customSections(
+      moduleObject: Module,
+      sectionName: string
+    ): ArrayBuffer;
+
+    /** Given a `Module`, returns an array containing descriptions of all the
+     * declared exports. */
+    static exports(moduleObject: Module): ModuleExportDescriptor[];
+
+    /** Given a `Module`, returns an array containing descriptions of all the
+     * declared imports. */
+    static imports(moduleObject: Module): ModuleImportDescriptor[];
+  }
+
+  class Instance<T extends object = { [key: string]: any }> {
+    constructor(module: Module, importObject?: object);
+
+    /** An object containing as its members all the functions exported from the
+     * WebAssembly module instance, to allow them to be accessed and used by
+     * JavaScript. */
+    readonly exports: T;
+  }
+
+  interface MemoryDescriptor {
+    initial: number;
+    maximum?: number;
+  }
+
+  class Memory {
+    constructor(descriptor: MemoryDescriptor);
+
+    /** An accessor property that returns the buffer contained in the memory. */
+    readonly buffer: ArrayBuffer;
+
+    /** Increases the size of the memory instance by a specified number of
+     * WebAssembly pages (each one is 64KB in size). */
+    grow(delta: number): number;
+  }
+
+  type TableKind = "anyfunc";
+
+  interface TableDescriptor {
+    element: TableKind;
+    initial: number;
+    maximum?: number;
+  }
+
+  class Table {
+    constructor(descriptor: TableDescriptor);
+
+    /** Returns the length of the table, i.e. the number of elements. */
+    readonly length: number;
+
+    /** Accessor function — gets the element stored at a given index. */
+    get(index: number): (...args: any[]) => any;
+
+    /** Increases the size of the Table instance by a specified number of
+     * elements. */
+    grow(delta: number): number;
+
+    /** Sets an element stored at a given index to a given value. */
+    set(index: number, value: (...args: any[]) => any): void;
+  }
+
+  type ValueType = "i32" | "i64" | "f32" | "f64";
+
+  interface GlobalDescriptor {
+    value: ValueType;
+    mutable?: boolean;
+  }
+
+  /** Represents a global variable instance, accessible from both JavaScript and
+   * importable/exportable across one or more `WebAssembly.Module` instances.
+   * This allows dynamic linking of multiple modules. */
+  class Global {
+    constructor(descriptor: GlobalDescriptor, value?: any);
+
+    /** Old-style method that returns the value contained inside the global
+     * variable. */
+    valueOf(): any;
+
+    /** The value contained inside the global variable — this can be used to
+     * directly set and get the global's value. */
+    value: any;
+  }
+
+  /** Indicates an error during WebAssembly decoding or validation */
+  class CompileError extends Error {
+    constructor(message: string, fileName?: string, lineNumber?: string);
+  }
+
+  /** Indicates an error during module instantiation (besides traps from the
+   * start function). */
+  class LinkError extends Error {
+    constructor(message: string, fileName?: string, lineNumber?: string);
+  }
+
+  /** Is thrown whenever WebAssembly specifies a trap. */
+  class RuntimeError extends Error {
+    constructor(message: string, fileName?: string, lineNumber?: string);
+  }
+}
+/* eslint-enable @typescript-eslint/no-unused-vars, @typescript-eslint/no-empty-interface, @typescript-eslint/no-explicit-any */
diff --git a/cli/js/lib.deno.worker.d.ts b/cli/js/lib.deno.worker.d.ts
new file mode 100644
index 000000000..07955345c
--- /dev/null
+++ b/cli/js/lib.deno.worker.d.ts
@@ -0,0 +1,45 @@
+// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
+
+/* eslint-disable @typescript-eslint/no-unused-vars, @typescript-eslint/no-empty-interface, @typescript-eslint/no-explicit-any */
+
+/// <reference no-default-lib="true" />
+/// <reference lib="deno_shared_globals" />
+/// <reference lib="esnext" />
+
+declare interface DedicatedWorkerGlobalScope extends WindowOrWorkerGlobalScope {
+  self: DedicatedWorkerGlobalScope &
+    WindowOrWorkerGlobalScope &
+    typeof globalThis;
+  onmessage: (e: { data: any }) => void;
+  onerror: undefined | typeof onerror;
+  name: typeof __workerMain.name;
+  close: typeof __workerMain.close;
+  postMessage: typeof __workerMain.postMessage;
+}
+
+declare const self: DedicatedWorkerGlobalScope &
+  WindowOrWorkerGlobalScope &
+  typeof globalThis;
+declare let onmessage: ((e: { data: any }) => Promise<void> | void) | undefined;
+declare let onerror:
+  | ((
+      msg: string,
+      source: string,
+      lineno: number,
+      colno: number,
+      e: Event
+    ) => boolean | void)
+  | undefined;
+declare const close: typeof __workerMain.close;
+declare const name: typeof __workerMain.name;
+declare const postMessage: typeof __workerMain.postMessage;
+
+declare namespace __workerMain {
+  export let onmessage: (e: { data: any }) => void;
+  export function postMessage(data: any): void;
+  export function getMessage(): Promise<any>;
+  export function close(): void;
+  export const name: string;
+}
+
+/* eslint-enable @typescript-eslint/no-unused-vars, @typescript-eslint/no-empty-interface, @typescript-eslint/no-explicit-any */
diff --git a/cli/js/lib.deno_worker.d.ts b/cli/js/lib.deno_worker.d.ts
deleted file mode 100644
index d7652807d..000000000
--- a/cli/js/lib.deno_worker.d.ts
+++ /dev/null
@@ -1,5 +0,0 @@
-// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
-
-/// <reference no-default-lib="true" />
-/// <reference lib="deno" />
-/// <reference lib="webworker" />
diff --git a/cli/js/runtime_worker.ts b/cli/js/runtime_worker.ts
index 7f1d1b69c..0dc65fdb6 100644
--- a/cli/js/runtime_worker.ts
+++ b/cli/js/runtime_worker.ts
@@ -54,7 +54,7 @@ export async function getMessage(): Promise<any> {
 let isClosing = false;
 let hasBootstrapped = false;
 
-export function workerClose(): void {
+export function close(): void {
   isClosing = true;
 }
 
@@ -102,7 +102,7 @@ export const workerRuntimeGlobalProperties = {
   self: readOnly(globalThis),
   onmessage: writable(onmessage),
   onerror: writable(onerror),
-  workerClose: nonEnumerable(workerClose),
+  close: nonEnumerable(close),
   postMessage: writable(postMessage)
 };
 
@@ -122,5 +122,6 @@ export function bootstrapWorkerRuntime(name: string): void {
   Object.defineProperties(globalThis, windowOrWorkerGlobalScopeProperties);
   Object.defineProperties(globalThis, workerRuntimeGlobalProperties);
   Object.defineProperties(globalThis, eventTargetProperties);
+  Object.defineProperties(globalThis, { name: readOnly(name) });
   runtime.start(false, name);
 }
diff --git a/cli/js/workers.ts b/cli/js/workers.ts
index 60ef73da0..2a5d4d190 100644
--- a/cli/js/workers.ts
+++ b/cli/js/workers.ts
@@ -27,12 +27,14 @@ function decodeMessage(dataIntArray: Uint8Array): any {
 function createWorker(
   specifier: string,
   hasSourceCode: boolean,
-  sourceCode: Uint8Array
+  sourceCode: Uint8Array,
+  name?: string
 ): { id: number; loaded: boolean } {
   return sendSync(dispatch.OP_CREATE_WORKER, {
     specifier,
     hasSourceCode,
-    sourceCode: new TextDecoder().decode(sourceCode)
+    sourceCode: new TextDecoder().decode(sourceCode),
+    name
   });
 }
 
@@ -72,10 +74,12 @@ export interface Worker {
   onmessage?: (e: { data: any }) => void;
   onmessageerror?: () => void;
   postMessage(data: any): void;
+  terminate(): void;
 }
 
 export interface WorkerOptions {
   type?: "classic" | "module";
+  name?: string;
 }
 
 export class WorkerImpl extends EventTarget implements Worker {
@@ -121,7 +125,12 @@ export class WorkerImpl extends EventTarget implements Worker {
     }
     */
 
-    const { id, loaded } = createWorker(specifier, hasSourceCode, sourceCode);
+    const { id, loaded } = createWorker(
+      specifier,
+      hasSourceCode,
+      sourceCode,
+      options?.name
+    );
     this.id = id;
     this.ready = loaded;
     this.poll();
@@ -196,6 +205,10 @@ export class WorkerImpl extends EventTarget implements Worker {
     hostPostMessage(this.id, data);
   }
 
+  terminate(): void {
+    throw new Error("Not yet implemented");
+  }
+
   private async run(): Promise<void> {
     while (!this.isClosing) {
       const data = await hostGetMessage(this.id);