diff --git a/index.d.ts b/index.d.ts
new file mode 100644
index 00000000..c4971e41
--- /dev/null
+++ b/index.d.ts
@@ -0,0 +1,689 @@
+export as namespace osjs__client;
+
+// Internal types
+
+export type WindowPositionString = 'center' | 'left' | 'right' | 'bottom' | 'top-left' | 'top-right' | 'bottom-left' | 'bottom-right'
+export type VFSFile = FileMetadata | string;
+export type VFSFileData = Blob | ArrayBuffer | File | string;
+
+// Internal interfaces
+
+export interface UserProfile {
+  id?: number;
+  username: string;
+  groups: string[];
+}
+
+// FIXME
+export interface CoreConfig {
+  development: boolean;
+  standalone: boolean;
+  http: object;
+  ws: object;
+  languages: Map<string, string>;
+  packages: object;
+  application: object;
+  auth: object;
+  settings: object;
+  search: object;
+  notifications: object;
+  desktop: object;
+  locale: object;
+  windows: object;
+  vfs: object;
+  providers: object;
+}
+
+export interface CoreOptions {
+  root?: Element
+  resourceRoot?: Element
+  classNames?: string[]
+}
+
+export interface ApplicationOptions {
+  settings?: object;
+  restore?: object;
+  windowAutoFocus: boolean;
+  sessionable: boolean;
+}
+
+export interface ApplicationData {
+  args?: Map<string, any>;
+  options?: ApplicationOptions;
+  metadata?: PackageMetadata;
+}
+
+export interface ApplicationSessionData {
+  args: Map<string, any>;
+  name: string;
+  windows: WindowSessionData[];
+}
+
+export interface WindowOptions {
+  id?: string;
+  title?: string;
+  parent?: Window;
+  template?: string | Function;
+  attributes?: WindowAttributes;
+  position?: WindowPosition | WindowPositionString;
+  dimension?: WindowDimension;
+  state?: WindowState;
+}
+
+export interface WindowDimension {
+  width: number;
+  height: number;
+}
+
+export interface WindowPosition {
+  top: number;
+  left: number;
+}
+
+export interface WindowState {
+  title: string;
+  icon: string;
+  moving: boolean;
+  resizing: boolean;
+  loading: boolean;
+  focused: boolean;
+  maximized: boolean;
+  minimized: boolean;
+  modal: boolean;
+  zIndex: number;
+  position: WindowPosition;
+  dimension: WindowDimension;
+}
+
+export interface WindowAttributes {
+  classNames: string[];
+  ontop: boolean;
+  gravity: string;
+  resizable: boolean;
+  focusable: boolean;
+  maximizable: boolean;
+  minimizable: boolean;
+  moveable: boolean;
+  closeable: boolean;
+  header: boolean;
+  controls: boolean;
+  visibility: string;
+  clamp: boolean;
+  minDimension: WindowDimension;
+  maxDimension: WindowDimension;
+  mediaQueries: Map<string, string>;
+}
+
+export interface WindowSessionData {
+  id: string;
+  position: WindowPosition;
+  dimension: WindowDimension;
+}
+
+export interface DesktopContextMenu {
+
+}
+
+export interface DesktopOptions {
+  contextmenu: DesktopContextMenu[] | Function;
+}
+
+export interface DesktopRect {
+  width: number;
+  height: number;
+  top: number;
+  bottom: number;
+  left: number;
+  right: number;
+}
+
+export interface PackageReference {
+  metadata: PackageMetadata;
+  callback: Function;
+}
+
+export interface PackageMetadata {
+  name: string;
+  category: string;
+  icon: string;
+  singleton: boolean;
+  autostart: boolean;
+  hidden: boolean;
+  server: string;
+  groups: string[];
+  files: string[];
+  title: Map<string, string>;
+  description: Map<string, string>;
+}
+
+export interface FileMetadata {
+  filename: string;
+  path: string;
+  mime?: string;
+  type: string;
+  size: number;
+  isDirectory: boolean;
+  isFile: boolean;
+  stat?: object;
+}
+
+export interface PackageLaunchOptions {
+  forcePreload: boolean;
+}
+
+export interface WebsocketOptions {
+  interval: number;
+  open: boolean;
+}
+
+export interface AuthOptions {
+  ui: object;
+  adapter(): AuthAdapter;
+  login: Function;
+  config: object;
+}
+
+export interface SettingsOptions {
+  adapter(): SettingsAdapter;
+}
+
+export interface AuthAdapter {
+  login(): Promise<UserProfile>;
+  logout(): Promise<boolean>;
+  init(): Promise<boolean>;
+  destroy(): void;
+}
+
+export interface SettingsAdapter {
+  load(): Promise<object>;
+  save(): Promise<boolean>;
+  init(): Promise<boolean>;
+  clear(): Promise<boolean>;
+  destroy(): void;
+}
+
+export interface ServiceProviderOptions {
+  before?: boolean;
+  depends?: string[];
+  args?: object;
+}
+
+export interface FilesystemAdapter extends VFSMethods {
+  mount(options?: object): Promise<boolean>;
+  unmount(options?: object): Promise<boolean>;
+}
+
+export interface MountpointAttributes {
+  visibility: string;
+  local: boolean;
+  searchable: boolean;
+  readOnly: boolean;
+}
+
+export interface Mountpoint {
+  name: string;
+  label: string;
+  adapter: string;
+  enabled: boolean;
+  attributes: MountpointAttributes;
+}
+
+export interface MountpointOptions extends Mountpoint {
+  /* blank */
+}
+
+export interface FilesystemOptions {
+  adapters: Map<string, FilesystemAdapter>;
+  mounts: Mountpoint[];
+}
+
+export interface LoginOptions {
+  id: string;
+  title: string;
+  stamp?: string;
+  logo: object;
+  fields: object;
+}
+
+export interface NotificationOptions {
+  icon: string | null;
+  title: string;
+  message: string;
+  timeout: number;
+  native: boolean;
+  sound?: string;
+}
+
+export interface TrayEntryOptions {
+  icon: string;
+  title: string;
+  onclick: Function;
+  oncontextmenu: Function;
+  handler?: Function;
+}
+
+export interface TrayEntry {
+  entry: TrayEntryOptions;
+  update(data: object): void;
+  destroy(): void;
+}
+
+export class EventEmitter {
+  constructor(name?: string);
+  on(event: string | string[], callback: Function): this;
+  once(event: string | string[], callback: Function): this;
+  off(event: string | string[], callback?: Function): this;
+  emit(event: string | string[], callback: Function): this;
+}
+
+export class ServiceProvider {
+  constructor(core: Core, options: object);
+  destroy(): void;
+  depends(): string[];
+  provides(): string[];
+  init(): Promise<any>;
+  start(): void;
+}
+
+export interface VFSMethods {
+  readdir(path: FileMetadata, options?: object): Promise<FileMetadata[]>;
+  readfile(path: FileMetadata, options?: object): Promise<VFSFileData>;
+  writefile(path: FileMetadata, data: VFSFileData, options?: object): Promise<number>;
+  copy(from: FileMetadata, to: FileMetadata, options?: object): Promise<boolean>;
+  rename(from: FileMetadata, to: FileMetadata, options?: object): Promise<boolean>;
+  mkdir(path: FileMetadata, options?: object): Promise<boolean>;
+  unlink(path: FileMetadata, options?: object): Promise<boolean>;
+  exists(path: FileMetadata, options?: object): Promise<boolean>;
+  touch(path: FileMetadata, options?: object): Promise<boolean>;
+  stat(path: FileMetadata, options?: object): Promise<FileMetadata>;
+  search(root: FileMetadata, pattern: string, options?: object): Promise<FileMetadata[]>;
+  url(path: FileMetadata, options?: object): Promise<string>;
+}
+
+export interface VFS extends VFSMethods {
+  download(path: FileMetadata, options?: object): Promise<any>;
+}
+
+// Utils
+
+export class Preloader {
+  loaded: string[];
+  $root: Element;
+
+  constructor(root: Element);
+  destroy(): void;
+  load(list: string[], force?: boolean): Promise<string[]>;
+}
+
+// Core
+
+export class Tray {
+  core: Core;
+  entries: TrayEntry[];
+
+  constructor(core: Core);
+  destroy(): void;
+  create(options: TrayEntryOptions, handler?: Function): void;
+  remove(entry: TrayEntry): void;
+}
+
+export class Desktop extends EventEmitter {
+  core: Core;
+  options: DesktopOptions;
+  $theme: Element[];
+  $icons: Element[];
+  $styles: Element;
+  contextMenuEntries: DesktopContextMenu[];
+  search?: Search;
+  subtract: Map<string, number>;
+
+  constructor(core: Core, options: DesktopOptions);
+  destroy(): void;
+  init(): void;
+  start(): void;
+  initConnectionEvents(): void;
+  initUIEvents(): void;
+  initDragEvents(): void;
+  initKeyboardEvents(): void;
+  initMouseEvents(): void;
+  initBaseEvents(): void;
+  initLocales(): void;
+  initDeveloperTray(): void;
+  addContextMenu(entries: DesktopContextMenu[]): void;
+  applySettings(settings: object): object;
+  applyIcons(name: string): Promise<any>;
+  applyTheme(name: string): Promise<any>;
+  onDeveloperMenu(ev: Event): void;
+  onContextMenu(ev: Event): void;
+  getRect(): DesktopRect;
+}
+
+export class Clipboard {
+  constructor();
+  destroy(): void;
+  clear(): void;
+  set(v: any): void;
+  get(clear?: boolean): Promise<any>;
+}
+
+export class Splash {
+  core: Core;
+  $loading: Element;
+
+  constructor(core: Core);
+  destroy(): void;
+  show(): void;
+}
+
+export class Search {
+  core: Core;
+  ui: EventEmitter;
+  focusLastWindow?: Window;
+  $element: Element;
+
+  constructor(core: Core);
+  destroy(): void;
+  init(): void;
+  search(pattern: string): FileMetadata[];
+  focus(): void;
+  hide(): void;
+  show(): void;
+}
+
+export class Auth {
+  core: Core;
+  callback: Function;
+  adapter: AuthAdapter;
+
+  constructor(core: Core, args: AuthOptions);
+  init(): Promise<boolean>;
+  destroy(): void;
+  shutdown(reload?: boolean): void;
+  show(cb: Function): Promise<boolean>;
+  login(values: object): Promise<boolean>;
+  logout(reload?: boolean): Promise<boolean>;
+}
+
+export class Session {
+  core: Core;
+
+  constructor(core: Core);
+  destroy(): void;
+  save(): Promise<boolean>;
+  load(fresh?: boolean): Promise<boolean>;
+}
+
+export class Settings {
+  core: Core;
+  adapter: SettingsAdapter;
+  debounce: any;
+  settings: Map<string, any>;
+
+  constructor(core: Core, args: SettingsOptions);
+  destroy(): void;
+  init(): Promise<boolean>;
+  save(): Promise<boolean>;
+  load(): Promise<boolean>;
+  get(ns: string, key: string, defaultValue?: any): any;
+  set(ns: string, key?: string, value?: any): this;
+  clear(ns: string): Promise<boolean>;
+}
+
+export class Filesystem extends EventEmitter {
+  core: Core;
+  adapters: Map<string, FilesystemAdapter>;
+  mounts: Mountpoint[];
+  options: FilesystemOptions;
+  proxy: Map<string, Function>;
+
+  constructor(core: Core, options: FilesystemOptions);
+  destroy(): void;
+  mountAll(stopOnError?: boolean): Promise<boolean>;
+  mount(name: string): Promise<boolean>;
+  unmount(name: string): Promise<boolean>;
+  request(): Map<string, Function>;
+  createMountpoint(props: MountpointOptions): void;
+  getMountpointFromPath(file: FileMetadata | string): Mountpoint | null;
+  getMounts(all?: boolean): Mountpoint[];
+}
+
+
+export class Login extends EventEmitter {
+  core: Core;
+  $container: Element;
+  options: LoginOptions;
+
+  constructor(core: Core, options: LoginOptions);
+  destroy(): void;
+  init(startHidden?: boolean): void;
+  render(startHidden?: boolean): void;
+}
+
+export class Notification {
+  core: Core;
+  $root: Element;
+  $element: Element;
+  destroyed: false;
+  options: NotificationOptions;
+
+  constructor(core: Core, root: Element, options: NotificationOptions);
+  destroy(): void;
+  render(): void;
+}
+
+export class Notifications {
+  core: Core;
+  $element: Element;
+
+  constructor(core: Core);
+  destroy(): void;
+  init(): void;
+  create(options: NotificationOptions): Notification;
+}
+
+export class Packages {
+  core: Core;
+  packages: PackageReference[];
+  metadata: PackageMetadata[];
+  running: string[];
+  preloader: Preloader;
+  inited: boolean;
+
+  constructor(core: Core);
+  destroy(): void;
+  init(): Promise<boolean>;
+  launch(name: string, args?: object, options?: PackageLaunchOptions): Promise<Application>; // FIXME
+  register(name: string, callback: Function): void;
+  addPackages(list: PackageMetadata[]): PackageMetadata[];
+  getPackages(filter?: Function): PackageMetadata[];
+  getCompatiblePackages(mimeType: string): PackageMetadata[];
+}
+
+export class Websocket extends EventEmitter {
+  constructor(name: string, uri: string, options: WebsocketOptions);
+  open(reconnect?: boolean): void;
+  send(...args: any): void;
+  close(): void;
+}
+
+export class Application extends EventEmitter {
+  pid: number;
+  core: Core;
+  args: Map<string, any>;
+  options: ApplicationOptions;
+  metadata: PackageMetadata;
+  settings: Map<string, any>;
+  windows: Window[];
+  workers: Worker[];
+  sockets: Websocket[];
+  requestOptions: Map<string, any>;
+  destroyed: boolean;
+  started: Date;
+
+  constructor(core: Core, data: ApplicationData);
+  destroy(remove?: boolean): void;
+  relaunch(): void;
+  resource(path?: string, options?: object): string;
+  request(path?: string, options?: object, type?: string): Promise<any>;
+  socket(path?: string, options?: object): Websocket;
+  worker(filename: string, options?: object): Worker;
+  send(...args: any): void;
+  createWindow(options?: WindowOptions): Window;
+  removeWindow(filter?: Function): void;
+  getSession(): ApplicationSessionData;
+  saveSettings(): Promise<boolean>;
+
+  static getApplications(): Application[];
+  static destroyAll(): void;
+}
+
+export class Window extends EventEmitter {
+  id: string;
+  wid: number;
+  parent?: Window;
+  children: Window[];
+  core: Core;
+  destroyed: boolean;
+  rendered: boolean;
+  attributes: WindowAttributes;
+  state: WindowState;
+  $element: Element;
+  $content: Element;
+  $header: Element;
+  $icon: Element;
+  $title: Element;
+
+  constructor(core: Core, options?: WindowOptions);
+  destroy(): void;
+  init(): this;
+  render(callback?: Function): this;
+  close(): this;
+  focus(): this;
+  blur(): this;
+  minimize(): this;
+  raise(): this;
+  maximize(): this;
+  restore(): this;
+  resizeFit(container: Element): void;
+  clampToViewport(update?: boolean): void;
+  gravitate(gravity: string): void;
+  setIcon(uri: string): void;
+  setTitle(title: string): void;
+  setDimension(dimension: WindowDimension): void;
+  setPosition(position: WindowPosition): void;
+  setZindex(zindex: number): void;
+  setState(name: string, value: any, update?: boolean): void;
+  getState(name: string): any;
+  getSession(): WindowSessionData | null;
+
+  private _toggleState(name: string, value: any, eventName: string, update?: boolean): boolean;
+  private _setState(name: string, value: any, update?: boolean): void;
+  private _updateDOM(): void;
+
+  static getWindows(): Window[];
+  static lastWindow(): Window;
+}
+
+export class Core extends EventEmitter {
+  ws: Websocket;
+  user: UserProfile;
+  options: CoreOptions;
+  $root: Element;
+  $resourceRoot: Element;
+
+  constructor(config?: CoreConfig, options?: CoreOptions);
+  destroy(): void;
+  boot(): Promise<boolean>;
+  start(): Promise<boolean>;
+  config(key?: string, defaultValue?: any): any;
+  register(ref: ServiceProvider, options?: ServiceProviderOptions): void;
+  instance(name: string, callback: Function): void;
+  singleton(name: string, callback: Function): void;
+  make(name: string, ...args: any): any; // FIXME
+  has(name: string): boolean;
+
+  url(endpoint?: string, options?: object, metadata?: object): string;
+  request(url: string, options?: object, type?: string): Promise<any>;
+  run(name: string, args?: object, options?: object): Promise<Application>;
+  open(file: VFSFile,  options?: object): Promise<Application>;
+  broadcast(pkg: string | Function, name: string, ...args: any): string[];
+  setRequestOptions(options: object): void;
+  getUser(): UserProfile;
+}
+
+// Service Provider Contracts
+
+export interface AuthServiceContract {
+  show(cb: Function): Promise<boolean>;
+  login(values: object): Promise<boolean>;
+  logout(reload?: boolean): Promise<boolean>;
+  user(): UserProfile;
+}
+
+export interface DesktopServiceContract {
+  addContextMenuEntries(entries: DesktopContextMenu[]): void;
+  applySettings(settings: object): object;
+  getRect(): DesktopRect;
+}
+
+export interface SettingsServiceContract {
+  save(): Promise<boolean>;
+  load(): Promise<boolean>;
+  get(ns: string, key: string, defaultValue?: any): any;
+  set(ns: string, key?: string, value?: any): this;
+  clear(ns: string): Promise<boolean>;
+}
+
+export interface VFSServiceContract extends VFSMethods {}
+
+export interface FilesystemServiceContract {
+  pathJoin(...args: string[]): string;
+  icon(name: string): string;
+  mountpoints(all?: boolean): Mountpoint[];
+  mount(name: string): Promise<boolean>;
+  unmount(name: string): Promise<boolean>;
+}
+
+export interface WindowsServiceContract {
+  create(options: WindowOptions): Window;
+  list(): Window[];
+  last(): Window;
+}
+
+export interface SessionServiceContract {
+  save(): Promise<boolean>;
+  load(): Promise<boolean>;
+}
+
+export interface LocaleServiceContract {
+  format(): string;
+  translate(): string;
+  translatable(): Function;
+  translatableFlat(): Function;
+  getLocale(): string;
+  setLocale(name: string): Promise<any>;
+}
+
+export interface PackagesServiceContract {
+  running(): string[];
+  launch(name: string, args?: object, options?: PackageLaunchOptions): Promise<Application>; // FIXME
+  register(name: string, callback: Function): void;
+  getPackages(filter?: Function): PackageMetadata[];
+  getCompatiblePackages(mimeType: string): PackageMetadata[];
+}
+
+export interface ClipboardServiceContract {
+  clear(): void;
+  set(v: any): void;
+  get(clear?: boolean): Promise<any>;
+}
+
+export interface ThemeServiceContract {
+  resource(name: string): string;
+  icon(name: string): string;
+}
+
+export interface SoundServiceContract {
+  resource(name: string): string;
+  play(src: string): Promise<boolean>;
+}
diff --git a/package.json b/package.json
index 53e00eff..0e3e72fb 100644
--- a/package.json
+++ b/package.json
@@ -4,12 +4,14 @@
   "description": "OS.js v3 client",
   "main": "dist/main.js",
   "style": "dist/main.css",
+  "types": "index.d.ts",
   "files": [
     "dist/main.js",
     "dist/main.js.map",
     "dist/main.css",
     "dist/main.css.map",
     "dist/*.png",
+    "index.d.ts",
     "README.md",
     "LICENSE"
   ],