diff --git a/README.md b/README.md
index 7a66fb2..81972dd 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,48 @@
-# webidl
+# WebIDL helpers for JavaScript
 
-📚 WebIDL infrastructure for making JavaScript ↔️ JavaScript bindings
+📚 [WebIDL] infrastructure for making JavaScript ↔️ JavaScript bindings
+
+<div align="center">
+
+![]()
+
+</div>
+
+## Installation
+
+```sh
+npm install @webfill/webidl
+```
+
+## Usage
+
+```js
+import { bindInterface, defineOperation, types } from "@webfill/webidl";
+
+class Dog {
+  bark() {
+    console.log("woof");
+  }
+  eat(food) {
+    console.log(`eating ${food}`);
+  }
+}
+Dog = bindInterface(Dog, "Dog");
+defineOperation(Dog.prototype, "bark", [], types.undefined)
+defineOperation(Dog.prototype, "eat", [types.DOMString], types.undefined);
+
+const dog = new Dog();
+//=> Uncaught TypeError: Illegal constructor
+
+const dog = Object.create(Dog.prototype);
+dog.bark();
+//=> 'woof'
+
+dog.eat();
+//=> Uncaught TypeError: Failed to execute 'eat' on 'Dog': 1 argument required, but only 0 present.
+
+dog.eat("🥩");
+//=> 'eating 🥩'
+```
+
+[WebIDL]: https://webidl.spec.whatwg.org/
diff --git a/package-lock.json b/package-lock.json
index b734a6f..c3d4ab1 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "@jcbhmr/webidl",
-  "version": "1.0.0",
+  "version": "0.1.0",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "@jcbhmr/webidl",
-      "version": "1.0.0",
+      "version": "0.1.0",
       "license": "MIT",
       "devDependencies": {
         "@types/node": "^20.2.5",
diff --git a/package.json b/package.json
index 89f19c1..def692f 100644
--- a/package.json
+++ b/package.json
@@ -20,6 +20,12 @@
   "type": "module",
   "exports": {
     ".": "./dist/index.js",
+    "./DOMException.js": {
+      "deno": "./src/DOMException.js",
+      "bun": "./src/DOMException.js",
+      "node": "./src/DOMException-node.js",
+      "default": "./src/DOMException.js"
+    },
     "./*.js": "./dist/*.js",
     "./internal/*": null
   },
diff --git a/src/DOMException-node-16.js b/src/DOMException-node-16.js
new file mode 100644
index 0000000..1e42968
--- /dev/null
+++ b/src/DOMException-node-16.js
@@ -0,0 +1,9 @@
+/** @type {typeof globalThis.DOMException} */
+let DOMException;
+try {
+  atob(1);
+} catch (error) {
+  DOMException = error.constructor;
+}
+
+export default DOMException;
diff --git a/src/DOMException-node.js b/src/DOMException-node.js
new file mode 100644
index 0000000..422a9bc
--- /dev/null
+++ b/src/DOMException-node.js
@@ -0,0 +1,9 @@
+/** @type {typeof globalThis.DOMException} */
+let DOMException;
+if (process.version.startsWith("v16")) {
+  ({ default: DOMException } = await import("./DOMException-node-16.js"));
+} else {
+  DOMException = globalThis.DOMException;
+}
+
+export default DOMException;
diff --git a/src/DOMException.js b/src/DOMException.js
new file mode 100644
index 0000000..3c01dfb
--- /dev/null
+++ b/src/DOMException.js
@@ -0,0 +1 @@
+export default DOMException;
diff --git a/src/bindInterface.js b/src/bindInterface.js
new file mode 100644
index 0000000..3a0c9dd
--- /dev/null
+++ b/src/bindInterface.js
@@ -0,0 +1,31 @@
+/**
+ * @template {{ new (...a: any[]): any }} T
+ * @param {T} Class
+ * @param {string} name
+ * @param {boolean} [constructable]
+ * @returns {T}
+ */
+export default function bindInterface(Class, name, constructable = undefined) {
+  Object.defineProperty(Class, "name", { value: name, configurable: true });
+  Object.defineProperty(Class.prototype, Symbol.toStringTag, {
+    value: name,
+    configurable: true,
+  });
+
+  if (constructable == null) {
+    constructable = /\Wconstructor\(/.test(
+      Function.prototype.toString.call(Class)
+    );
+  }
+
+  if (!constructable) {
+    Object.defineProperty(Class, "length", { value: 0, configurable: true });
+    Class = new Proxy(Class, {
+      construct() {
+        throw new TypeError(`Illegal constructor`);
+      },
+    });
+  }
+
+  return Class;
+}
diff --git a/src/defineAttribute.js b/src/defineAttribute.js
new file mode 100644
index 0000000..5ca6aad
--- /dev/null
+++ b/src/defineAttribute.js
@@ -0,0 +1,32 @@
+/**
+ * @template {object} O
+ * @template {keyof O | string} N
+ * @template {{ from(x: unknown): any }[]} T
+ * @param {O} object
+ * @param {N} name
+ * @param {T} [attrType]
+ * @returns {O}
+ */
+export default function defineAttribute(object, name, attrType = undefined) {
+  const { get, set } = Object.getOwnPropertyDescriptor(object, name);
+  Object.defineProperty(object, name, {
+    get() {
+      let x = get.call(this);
+      if (attrType) {
+        x = attrType.from(x);
+      }
+      return x;
+    },
+    ...(set && {
+      set(x) {
+        if (attrType) {
+          x = attrType.from(x);
+        }
+        set.call(this, x);
+      },
+    }),
+    enumerable: true,
+    configurable: true,
+  });
+  return object;
+}
diff --git a/src/defineExtendedAttribute.js b/src/defineExtendedAttribute.js
new file mode 100644
index 0000000..ba5f73a
--- /dev/null
+++ b/src/defineExtendedAttribute.js
@@ -0,0 +1,17 @@
+/**
+ * @template {object} O
+ * @param {O} object
+ * @param {keyof O | string} name
+ * @param {(t: "descriptor", d: PropertyDescriptor) => PropertyDescriptor | null | undefined} ExtendedAttribute
+ * @returns {O}
+ */
+export default function defineExtendedAttribute(
+  object,
+  name,
+  ExtendedAttribute
+) {
+  let d = Object.getOwnPropertyDescriptor(object, name);
+  d = ExtendedAttribute("descriptor", d) ?? d;
+  Object.defineProperty(object, name, d);
+  return object;
+}
diff --git a/src/defineOperation.js b/src/defineOperation.js
new file mode 100644
index 0000000..2104123
--- /dev/null
+++ b/src/defineOperation.js
@@ -0,0 +1,41 @@
+/**
+ * @template {object} O
+ * @template {keyof O | string} N
+ * @template {{ from(x: unknown): any }[]} A
+ * @template {{ from(x: any): any }} R
+ * @param {O} object
+ * @param {N} name
+ * @param {A} [argTypes]
+ * @param {R} [returnType]
+ * @returns {O}
+ */
+export default function defineOperation(
+  object,
+  name,
+  argTypes = undefined,
+  returnType = undefined
+) {
+  const original = object[name];
+  const { value } = {
+    value() {
+      if (argTypes) {
+        for (const [i, argType] of argTypes.entries()) {
+          arguments[i] = argType.from(arguments[i]);
+        }
+      }
+      let result = original.apply(this, arguments);
+      if (returnType) {
+        result = returnType.from(result);
+      }
+      return result;
+    },
+  };
+  Object.defineProperties(value, Object.getOwnPropertyDescriptors(original));
+  Object.defineProperty(object, name, {
+    value,
+    writable: true,
+    enumerable: true,
+    configurable: true,
+  });
+  return object;
+}
diff --git a/src/extended-attributes/Global.js b/src/extended-attributes/Global.js
new file mode 100644
index 0000000..4d01717
--- /dev/null
+++ b/src/extended-attributes/Global.js
@@ -0,0 +1,20 @@
+/**
+ * @param {string | string[]} nameOrNames
+ * @returns {(t: "value", n: string, v: any) => void}
+ */
+export default function Global(nameOrNames) {
+  const names = Array.isArray(nameOrNames) ? nameOrNames : [nameOrNames];
+  return (t, n, v) => {
+    for (const name of names) {
+      if (isInstanceOf(globalThis, name)) {
+        Object.defineProperty(globalThis, n, {
+          value: v,
+          writable: true,
+          configurable: true,
+          enumerable: true,
+        });
+        return;
+      }
+    }
+  };
+}
diff --git a/src/index.ts b/src/index.js
similarity index 63%
rename from src/index.ts
rename to src/index.js
index c40b671..d60147f 100644
--- a/src/index.ts
+++ b/src/index.js
@@ -1,3 +1,3 @@
 export * as types from "./types/index.js";
-export { default as interface_ } from "./interface_.js";
+export { default as interface_ } from "./interface.js";
 export { default as operation } from "./operation.js";
diff --git a/src/interface_.ts b/src/interface_.ts
deleted file mode 100644
index 3ec046c..0000000
--- a/src/interface_.ts
+++ /dev/null
@@ -1,23 +0,0 @@
-import { Class } from "./internal/REF-type-fest/basic.js";
-
-export default function interface_<T extends Class<{}>>(
-  name: string,
-  Class: T
-): T {
-  Object.defineProperty(Class, "name", { value: name, configurable: true });
-  Object.defineProperty(Class.prototype, Symbol.toStringTag, {
-    value: name,
-    configurable: true,
-  });
-
-  if (/\Wconstructor\(/.test(Function.prototype.toString.call(Class))) {
-    return Class;
-  } else {
-    Object.defineProperty(Class, "length", { value: 0, configurable: true });
-    return new Proxy<T>(Class, {
-      construct() {
-        throw new TypeError(`Illegal constructor`);
-      },
-    });
-  }
-}
diff --git a/src/internal/REF-type-fest/README.md b/src/internal/REF-type-fest/README.md
deleted file mode 100644
index 34c2849..0000000
--- a/src/internal/REF-type-fest/README.md
+++ /dev/null
@@ -1 +0,0 @@
-https://github.com/sindresorhus/type-fest#readme
diff --git a/src/internal/REF-type-fest/basic.d.ts b/src/internal/REF-type-fest/basic.d.ts
deleted file mode 100644
index 41c972d..0000000
--- a/src/internal/REF-type-fest/basic.d.ts
+++ /dev/null
@@ -1,20 +0,0 @@
-/**
- * Matches a
- * [`class`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes).
- *
- * @category Class
- */
-export type Class<T, Arguments extends unknown[] = any[]> = Constructor<
-  T,
-  Arguments
-> & { prototype: T };
-
-/**
- * Matches a [`class`
- * constructor](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes).
- *
- * @category Class
- */
-export type Constructor<T, Arguments extends unknown[] = any[]> = new (
-  ...arguments_: Arguments
-) => T;
diff --git a/src/internal/isInstanceOf.js b/src/internal/isInstanceOf.js
new file mode 100644
index 0000000..e37b19b
--- /dev/null
+++ b/src/internal/isInstanceOf.js
@@ -0,0 +1,8 @@
+export function isInstanceOf(value, classOrClassName) {
+  for (let p = value; p; p = Object.getPrototypeOf(p)) {
+    if (Object.prototype.toString.call(p).slice(8, -1) === classOrClassName) {
+      return true;
+    }
+  }
+  return false;
+}
diff --git a/src/operation.ts b/src/operation.ts
deleted file mode 100644
index 143cf6d..0000000
--- a/src/operation.ts
+++ /dev/null
@@ -1,34 +0,0 @@
-type Coercer<T> = { from(x: unknown): T };
-
-function operation<
-  R extends Coercer<unknown>,
-  A extends Coercer<unknown>[],
-  F extends (...a: any[]) => any
->(returnType: R, argumentTypes: A, function_: F): F {
-  function w(this: ThisType<F>, ...a: Parameters<F>): ReturnType<F> {
-    if (a.length < function_.length) {
-      throw new TypeError(
-        `Failed to execute '${function_.name}' on '${this}': ${
-          function_.length
-        } argument${function_.length === 1 ? "" : "s"} required, but only ${
-          a.length
-        } present.`
-      );
-    }
-
-    const c = a.map((x, i) =>
-      i < argumentTypes.length ? argumentTypes[i].from(x) : x
-    );
-    const r = function_.call(this, ...c);
-    return returnType.from(r) as ReturnType<F>;
-  }
-  const s = Object.getOwnPropertyDescriptors(function_);
-  delete s.arguments;
-  delete s.caller;
-  delete s.callee;
-  delete s.prototype;
-  Object.defineProperties(w, s);
-  return w as F;
-}
-
-export default operation;
diff --git a/src/types/DOMString.js b/src/types/DOMString.js
new file mode 100644
index 0000000..08af636
--- /dev/null
+++ b/src/types/DOMString.js
@@ -0,0 +1,11 @@
+/** @typedef {string} DOMString */
+const DOMString = {
+  /**
+   * @param {unknown} x
+   * @returns {DOMString}
+   */
+  from(x) {
+    return `${x}`;
+  },
+};
+export default DOMString;
diff --git a/src/types/DOMString.ts b/src/types/DOMString.ts
deleted file mode 100644
index 09264a3..0000000
--- a/src/types/DOMString.ts
+++ /dev/null
@@ -1,8 +0,0 @@
-type DOMString = string;
-const DOMString = {
-  from(x: unknown): DOMString {
-    return `${x}`;
-  },
-};
-
-export default DOMString;
diff --git a/src/types/index.ts b/src/types/index.js
similarity index 63%
rename from src/types/index.ts
rename to src/types/index.js
index d938506..7273233 100644
--- a/src/types/index.ts
+++ b/src/types/index.js
@@ -1,3 +1,3 @@
 export { default as DOMString } from "./DOMString.js";
 export { default as long } from "./long.js";
-export { default as undefined_ } from "./undefined_.js";
+export { default as undefined } from "./undefined.js";
diff --git a/src/types/long.ts b/src/types/long.js
similarity index 99%
rename from src/types/long.ts
rename to src/types/long.js
index e7f80b6..819d9da 100644
--- a/src/types/long.ts
+++ b/src/types/long.js
@@ -5,5 +5,4 @@ const long = {
     return Math.trunc(x);
   },
 };
-
 export default long;
diff --git a/src/types/undefined_.ts b/src/types/undefined.js
similarity index 99%
rename from src/types/undefined_.ts
rename to src/types/undefined.js
index a6b0d95..d8ae7cb 100644
--- a/src/types/undefined_.ts
+++ b/src/types/undefined.js
@@ -4,5 +4,4 @@ const undefined_ = {
     return undefined;
   },
 };
-
 export default undefined_;
diff --git a/test/types/index.test.ts b/test/types/index.test.ts
deleted file mode 100644
index b9cf6d1..0000000
--- a/test/types/index.test.ts
+++ /dev/null
@@ -1,7 +0,0 @@
-import test from "node:test";
-import assert from "node:assert";
-import * as types from "../../src/types/index.js";
-
-test("types", async (t) => {
-  console.log(types);
-});
diff --git a/tsconfig.json b/tsconfig.json
deleted file mode 100644
index a587366..0000000
--- a/tsconfig.json
+++ /dev/null
@@ -1,21 +0,0 @@
-{
-  "compilerOptions": {
-    "outDir": "dist",
-    "declaration": true,
-    "target": "ESNext",
-    "module": "ESNext",
-    "moduleResolution": "nodenext",
-    "allowSyntheticDefaultImports": true,
-    "esModuleInterop": true,
-    "isolatedModules": true,
-    "strict": true,
-    "skipLibCheck": true
-  },
-  "include": ["src"],
-  "exclude": ["node_modules", "dist"],
-  "typedocOptions": {
-    "entryPoints": ["src/index.ts"],
-    "out": "docs/dist",
-    "skipErrorChecking": true
-  }
-}
diff --git a/wiki/Decorators.md b/wiki/Decorators.md
deleted file mode 100644
index 0a5566d..0000000
--- a/wiki/Decorators.md
+++ /dev/null
@@ -1,105 +0,0 @@
-https://github.com/tc39/proposal-decorators
-
-```ts
-type Decorator = (
-  value: Input,
-  context: {
-    kind: string;
-    name: string | symbol;
-    access: {
-      get?(): unknown;
-      set?(value: unknown): void;
-    };
-    private?: boolean;
-    static?: boolean;
-    addInitializer?(initializer: () => void): void;
-  }
-) => Output | void;
-```
-
-```ts
-type ClassMethodDecorator = (
-  value: Function,
-  context: {
-    kind: "method";
-    name: string | symbol;
-    access: { get(): unknown };
-    static: boolean;
-    private: boolean;
-    addInitializer(initializer: () => void): void;
-  }
-) => Function | void;
-```
-
-```ts
-type ClassGetterDecorator = (
-  value: Function,
-  context: {
-    kind: "getter";
-    name: string | symbol;
-    access: { get(): unknown };
-    static: boolean;
-    private: boolean;
-    addInitializer(initializer: () => void): void;
-  }
-) => Function | void;
-```
-
-```ts
-type ClassSetterDecorator = (
-  value: Function,
-  context: {
-    kind: "setter";
-    name: string | symbol;
-    access: { set(value: unknown): void };
-    static: boolean;
-    private: boolean;
-    addInitializer(initializer: () => void): void;
-  }
-) => Function | void;
-```
-
-```ts
-type ClassFieldDecorator = (
-  value: undefined,
-  context: {
-    kind: "field";
-    name: string | symbol;
-    access: { get(): unknown; set(value: unknown): void };
-    static: boolean;
-    private: boolean;
-  }
-) => (initialValue: unknown) => unknown | void;
-```
-
-```ts
-type ClassDecorator = (
-  value: Function,
-  context: {
-    kind: "class";
-    name: string | undefined;
-    addInitializer(initializer: () => void): void;
-  }
-) => Function | void;
-```
-
-```ts
-type ClassAutoAccessorDecorator = (
-  value: {
-    get: () => unknown;
-    set(value: unknown) => void;
-  },
-  context: {
-    kind: "accessor";
-    name: string | symbol;
-    access: { get(): unknown, set(value: unknown): void };
-    static: boolean;
-    private: boolean;
-    addInitializer(initializer: () => void): void;
-  }
-) => {
-  get?: () => unknown;
-  set?: (value: unknown) => void;
-  init?: (initialValue: unknown) => unknown;
-} | void;
-```