diff --git a/packages/docusaurus-plugin-content-blog/package.json b/packages/docusaurus-plugin-content-blog/package.json
index 9c7a11714c..2aa38e1cbc 100644
--- a/packages/docusaurus-plugin-content-blog/package.json
+++ b/packages/docusaurus-plugin-content-blog/package.json
@@ -10,6 +10,9 @@
     "access": "public"
   },
   "license": "MIT",
+  "devDependencies": {
+    "@docusaurus/types": "^2.0.0-alpha.24"
+  },
   "dependencies": {
     "@docusaurus/mdx-loader": "^2.0.0-alpha.24",
     "@docusaurus/utils": "^2.0.0-alpha.24",
diff --git a/packages/docusaurus-plugin-content-blog/src/__tests__/index.test.ts b/packages/docusaurus-plugin-content-blog/src/__tests__/index.test.ts
index cf0945799a..756d2a5ebc 100644
--- a/packages/docusaurus-plugin-content-blog/src/__tests__/index.test.ts
+++ b/packages/docusaurus-plugin-content-blog/src/__tests__/index.test.ts
@@ -8,7 +8,7 @@
 import fs from 'fs-extra';
 import path from 'path';
 import pluginContentBlog from '../index';
-import {DocusaurusConfig} from '../typesDocusaurus';
+import {DocusaurusConfig} from '@docusaurus/types';
 
 describe('loadBlog', () => {
   test('simple website', async () => {
diff --git a/packages/docusaurus-plugin-content-blog/src/index.ts b/packages/docusaurus-plugin-content-blog/src/index.ts
index 3059c624ea..5ed86e0fa5 100644
--- a/packages/docusaurus-plugin-content-blog/src/index.ts
+++ b/packages/docusaurus-plugin-content-blog/src/index.ts
@@ -19,13 +19,13 @@ import {
   BlogContent,
   BlogItemsToModules,
   TagsModule,
-  ConfigureWebpackUtils,
 } from './types';
 import {
   LoadContext,
   PluginContentLoadedActions,
   RouteModule,
-} from './typesDocusaurus';
+  ConfigureWebpackUtils,
+} from '@docusaurus/types';
 import {Configuration} from 'webpack';
 
 // YYYY-MM-DD-{name}.mdx?
@@ -57,7 +57,7 @@ export default function pluginContentBlog(
   context: LoadContext,
   opts: Partial<PluginOptions>,
 ) {
-  const options = {...DEFAULT_OPTIONS, ...opts};
+  const options: PluginOptions = {...DEFAULT_OPTIONS, ...opts};
   const contentPath = path.resolve(context.siteDir, options.path);
 
   return {
@@ -79,7 +79,7 @@ export default function pluginContentBlog(
         return null;
       }
 
-      const {baseUrl} = siteConfig;
+      const {baseUrl = ''} = siteConfig;
       const blogFiles = await globby(include, {
         cwd: blogDir,
       });
diff --git a/packages/docusaurus-plugin-content-blog/src/types.ts b/packages/docusaurus-plugin-content-blog/src/types.ts
index 5b011a5dd6..0c8076e9c7 100644
--- a/packages/docusaurus-plugin-content-blog/src/types.ts
+++ b/packages/docusaurus-plugin-content-blog/src/types.ts
@@ -1,5 +1,3 @@
-import {Loader} from 'webpack';
-
 export interface BlogContent {
   blogPosts: BlogPost[];
   blogListPaginated: BlogPaginated[];
@@ -80,14 +78,3 @@ export interface TagModule {
   count: number;
   permalink: string;
 }
-
-export interface ConfigureWebpackUtils {
-  getStyleLoaders: (
-    isServer: boolean,
-    cssOptions: {
-      [key: string]: any;
-    },
-  ) => Loader[];
-  getCacheLoader: (isServer: boolean, cacheOptions?: {}) => Loader | null;
-  getBabelLoader: (isServer: boolean, babelOptions?: {}) => Loader;
-}
diff --git a/packages/docusaurus-plugin-content-blog/src/typesDocusaurus.ts b/packages/docusaurus-plugin-content-blog/src/typesDocusaurus.ts
deleted file mode 100644
index 383cde0e2c..0000000000
--- a/packages/docusaurus-plugin-content-blog/src/typesDocusaurus.ts
+++ /dev/null
@@ -1,63 +0,0 @@
-import {ParsedUrlQueryInput} from 'querystring';
-
-export interface DocusaurusConfig {
-  baseUrl: string;
-  favicon?: string;
-  tagline?: string;
-  title: string;
-  url: string;
-  organizationName?: string;
-  projectName?: string;
-  githubHost?: string;
-  plugins?: PluginConfig[];
-  themes?: PluginConfig[];
-  presets?: PresetConfig[];
-  themeConfig?: {
-    [key: string]: any;
-  };
-  customFields?: {
-    [key: string]: any;
-  };
-}
-
-export type PluginConfig = [string, Object | undefined] | string;
-
-export type PresetConfig = [string, Object | undefined] | string;
-
-export interface CLIOptions {
-  [option: string]: any;
-}
-
-export interface LoadContext {
-  siteDir: string;
-  generatedFilesDir?: string;
-  siteConfig: DocusaurusConfig;
-  cliOptions?: CLIOptions;
-  outDir?: string;
-  baseUrl?: string;
-}
-
-export interface PluginContentLoadedActions {
-  addRoute(config: RouteConfig): void;
-  createData(name: string, data: Object): Promise<string>;
-}
-
-export type Module =
-  | {
-      path: string;
-      __import?: boolean;
-      query?: ParsedUrlQueryInput;
-    }
-  | string;
-
-export interface RouteModule {
-  [module: string]: Module | RouteModule | RouteModule[];
-}
-
-export interface RouteConfig {
-  path: string;
-  component: string;
-  modules?: RouteModule;
-  routes?: RouteConfig[];
-  exact?: boolean;
-}
diff --git a/packages/docusaurus-types/package.json b/packages/docusaurus-types/package.json
new file mode 100644
index 0000000000..60241aa859
--- /dev/null
+++ b/packages/docusaurus-types/package.json
@@ -0,0 +1,15 @@
+{
+  "name": "@docusaurus/types",
+  "version": "2.0.0-alpha.24",
+  "description": "Common used typings for Docusaurus packages",
+  "main": "./src/index.js",
+  "types": "./src/index.d.ts",
+  "publishConfig": {
+    "access": "public"
+  },
+  "license": "MIT",
+  "dependencies": {
+    "@types/webpack": "^4.32.0",
+    "querystring": "0.2.0"
+  }
+}
diff --git a/packages/docusaurus/src/server/types.ts b/packages/docusaurus-types/src/index.d.ts
similarity index 75%
rename from packages/docusaurus/src/server/types.ts
rename to packages/docusaurus-types/src/index.d.ts
index 893cedf735..3e864bdd20 100644
--- a/packages/docusaurus/src/server/types.ts
+++ b/packages/docusaurus-types/src/index.d.ts
@@ -1,5 +1,5 @@
+import {Loader, Configuration} from 'webpack';
 import {ParsedUrlQueryInput} from 'querystring';
-import {Configuration} from 'webpack';
 
 export interface DocusaurusConfig {
   baseUrl: string;
@@ -21,12 +21,16 @@ export interface DocusaurusConfig {
   };
 }
 
+export interface DocusaurusContext {
+  siteConfig?: Partial<DocusaurusConfig>;
+}
+
 export interface Preset {
   plugins?: PluginConfig[];
   themes?: PluginConfig[];
 }
 
-export type PresetConfig = [string, Object | undefined] | string;
+export type PresetConfig = [string, Object] | [string] | string;
 
 export interface CLIOptions {
   [option: string]: any;
@@ -35,7 +39,7 @@ export interface CLIOptions {
 export interface LoadContext {
   siteDir: string;
   generatedFilesDir: string;
-  siteConfig: DocusaurusConfig;
+  siteConfig: Partial<DocusaurusConfig>;
   cliOptions: CLIOptions;
   outDir: string;
   baseUrl: string;
@@ -68,7 +72,8 @@ export interface Plugin<T> {
   getPathsToWatch?(): string[];
   getClientModules?(): string[];
 }
-export type PluginConfig = [string, Object | undefined] | string;
+
+export type PluginConfig = [string, Object] | [string] | string;
 
 export interface ChunkRegistry {
   importStatement: string;
@@ -98,3 +103,14 @@ export interface RouteConfig {
 export interface ThemeAlias {
   [alias: string]: string;
 }
+
+export interface ConfigureWebpackUtils {
+  getStyleLoaders: (
+    isServer: boolean,
+    cssOptions: {
+      [key: string]: any;
+    },
+  ) => Loader[];
+  getCacheLoader: (isServer: boolean, cacheOptions?: {}) => Loader | null;
+  getBabelLoader: (isServer: boolean, babelOptions?: {}) => Loader;
+}
diff --git a/packages/docusaurus-types/src/index.js b/packages/docusaurus-types/src/index.js
new file mode 100644
index 0000000000..af4fc2ffc3
--- /dev/null
+++ b/packages/docusaurus-types/src/index.js
@@ -0,0 +1,3 @@
+/* eslint-disable */
+'use strict';
+Object.defineProperty(exports, '__esModule', {value: true});
diff --git a/packages/docusaurus/package.json b/packages/docusaurus/package.json
index da1c48f7a0..4173d2fe93 100644
--- a/packages/docusaurus/package.json
+++ b/packages/docusaurus/package.json
@@ -28,6 +28,9 @@
   "bugs": {
     "url": "https://github.com/facebook/Docusaurus/issues"
   },
+  "devDependencies": {
+    "@docusaurus/types": "^2.0.0-alpha.24"
+  },
   "dependencies": {
     "@babel/core": "^7.6.2",
     "@babel/plugin-syntax-dynamic-import": "^7.2.0",
diff --git a/packages/docusaurus/src/client/exports/context.ts b/packages/docusaurus/src/client/exports/context.ts
index c5150715ce..eb95258c39 100644
--- a/packages/docusaurus/src/client/exports/context.ts
+++ b/packages/docusaurus/src/client/exports/context.ts
@@ -6,6 +6,6 @@
  */
 
 import * as React from 'react';
-import {DocusaurusContext} from '../types';
+import {DocusaurusContext} from '@docusaurus/types';
 
 export default React.createContext<DocusaurusContext>({});
diff --git a/packages/docusaurus/src/client/exports/useDocusaurusContext.ts b/packages/docusaurus/src/client/exports/useDocusaurusContext.ts
index 096b868d97..953cb3ff98 100644
--- a/packages/docusaurus/src/client/exports/useDocusaurusContext.ts
+++ b/packages/docusaurus/src/client/exports/useDocusaurusContext.ts
@@ -7,7 +7,7 @@
 
 import {useContext} from 'react';
 import context from './context';
-import {DocusaurusContext} from '../types';
+import {DocusaurusContext} from '@docusaurus/types';
 
 function useDocusaurusContext(): DocusaurusContext {
   return useContext(context);
diff --git a/packages/docusaurus/src/client/types.ts b/packages/docusaurus/src/client/types.ts
deleted file mode 100644
index 08344f12c4..0000000000
--- a/packages/docusaurus/src/client/types.ts
+++ /dev/null
@@ -1,5 +0,0 @@
-import {DocusaurusConfig} from '../server/types';
-
-export interface DocusaurusContext {
-  siteConfig?: DocusaurusConfig;
-}
diff --git a/packages/docusaurus/src/commands/build.ts b/packages/docusaurus/src/commands/build.ts
index d6a302ab3d..de192fe2d3 100644
--- a/packages/docusaurus/src/commands/build.ts
+++ b/packages/docusaurus/src/commands/build.ts
@@ -16,7 +16,7 @@ import {BundleAnalyzerPlugin} from 'webpack-bundle-analyzer';
 import merge from 'webpack-merge';
 import {STATIC_DIR_NAME} from '../constants';
 import {load} from '../server';
-import {CLIOptions, Props} from '../server/types';
+import {CLIOptions, Props} from '@docusaurus/types';
 import {createClientConfig} from '../webpack/client';
 import {createServerConfig} from '../webpack/server';
 import {applyConfigureWebpack} from '../webpack/utils';
diff --git a/packages/docusaurus/src/commands/start.ts b/packages/docusaurus/src/commands/start.ts
index cc352d5de4..7ac7364cd4 100644
--- a/packages/docusaurus/src/commands/start.ts
+++ b/packages/docusaurus/src/commands/start.ts
@@ -20,7 +20,7 @@ import WebpackDevServer from 'webpack-dev-server';
 import merge from 'webpack-merge';
 import HotModuleReplacementPlugin from 'webpack/lib/HotModuleReplacementPlugin';
 import {load} from '../server';
-import {CLIOptions} from '../server/types';
+import {CLIOptions} from '@docusaurus/types';
 import {CONFIG_FILE_NAME, STATIC_DIR_NAME, DEFAULT_PORT} from '../constants';
 import {createClientConfig} from '../webpack/client';
 import {applyConfigureWebpack} from '../webpack/utils';
diff --git a/packages/docusaurus/src/server/client-modules/__tests__/index.test.ts b/packages/docusaurus/src/server/client-modules/__tests__/index.test.ts
index 21ef38902e..ac94a164ca 100644
--- a/packages/docusaurus/src/server/client-modules/__tests__/index.test.ts
+++ b/packages/docusaurus/src/server/client-modules/__tests__/index.test.ts
@@ -8,7 +8,6 @@
 import path from 'path';
 
 import {loadClientModules} from '../index';
-import {LoadContext} from '../../index';
 
 const pluginEmpty = require('./__fixtures__/plugin-empty');
 const pluginFooBar = require('./__fixtures__/plugin-foo-bar');
diff --git a/packages/docusaurus/src/server/client-modules/index.ts b/packages/docusaurus/src/server/client-modules/index.ts
index 0996d2f638..c9fd730000 100644
--- a/packages/docusaurus/src/server/client-modules/index.ts
+++ b/packages/docusaurus/src/server/client-modules/index.ts
@@ -6,7 +6,7 @@
  */
 
 import _ from 'lodash';
-import {Plugin} from '../types';
+import {Plugin} from '@docusaurus/types';
 
 export function loadClientModules(plugins: Plugin<any>[]): string[] {
   return _.compact(
diff --git a/packages/docusaurus/src/server/config.ts b/packages/docusaurus/src/server/config.ts
index 3816d0edf8..5e0fe9a779 100644
--- a/packages/docusaurus/src/server/config.ts
+++ b/packages/docusaurus/src/server/config.ts
@@ -10,7 +10,7 @@ import importFresh from 'import-fresh';
 import _ from 'lodash';
 import path from 'path';
 import {CONFIG_FILE_NAME} from '../constants';
-import {DocusaurusConfig, PluginConfig} from './types';
+import {DocusaurusConfig, PluginConfig} from '@docusaurus/types';
 
 const REQUIRED_FIELDS = ['baseUrl', 'favicon', 'tagline', 'title', 'url'];
 
diff --git a/packages/docusaurus/src/server/index.ts b/packages/docusaurus/src/server/index.ts
index ef0ff85b4b..696ad9b4cc 100644
--- a/packages/docusaurus/src/server/index.ts
+++ b/packages/docusaurus/src/server/index.ts
@@ -26,7 +26,7 @@ import {
   LoadContext,
   PluginConfig,
   Props,
-} from './types';
+} from '@docusaurus/types';
 
 export async function load(
   siteDir: string,
diff --git a/packages/docusaurus/src/server/loadSetup.ts b/packages/docusaurus/src/server/loadSetup.ts
index 9cf9b2f554..f148c0c9c2 100644
--- a/packages/docusaurus/src/server/loadSetup.ts
+++ b/packages/docusaurus/src/server/loadSetup.ts
@@ -7,7 +7,7 @@
 
 import path from 'path';
 import {load} from './index';
-import {Props} from './types';
+import {Props} from '@docusaurus/types';
 
 // Helper methods to setup dummy/fake projects
 export const loadSetup = async (name: string): Promise<Props> => {
diff --git a/packages/docusaurus/src/server/plugins/index.ts b/packages/docusaurus/src/server/plugins/index.ts
index 39aef6b5d2..87ac6cb1d9 100644
--- a/packages/docusaurus/src/server/plugins/index.ts
+++ b/packages/docusaurus/src/server/plugins/index.ts
@@ -16,7 +16,7 @@ import {
   PluginConfig,
   PluginContentLoadedActions,
   RouteConfig,
-} from '../types';
+} from '@docusaurus/types';
 
 export async function loadPlugins({
   pluginConfigs,
diff --git a/packages/docusaurus/src/server/presets/__tests__/index.test.ts b/packages/docusaurus/src/server/presets/__tests__/index.test.ts
index 68820e17aa..972d7631f2 100644
--- a/packages/docusaurus/src/server/presets/__tests__/index.test.ts
+++ b/packages/docusaurus/src/server/presets/__tests__/index.test.ts
@@ -8,7 +8,7 @@
 import path from 'path';
 
 import {loadPresets} from '../index';
-import {LoadContext} from '../../index';
+import {DocusaurusConfig, LoadContext} from '@docusaurus/types';
 
 describe('loadPresets', () => {
   test('no presets', () => {
@@ -86,7 +86,7 @@ describe('loadPresets', () => {
       siteConfig: {
         presets: [[path.join(__dirname, '__fixtures__/preset-bar.js')]],
       },
-    } as LoadContext;
+    } as Partial<LoadContext>;
     const presets = loadPresets(context);
     expect(presets).toMatchInlineSnapshot(`
       Object {
@@ -115,7 +115,7 @@ describe('loadPresets', () => {
           ],
         ],
       },
-    } as LoadContext;
+    } as Partial<LoadContext>;
     const presets = loadPresets(context);
     expect(presets).toMatchInlineSnapshot(`
       Object {
@@ -150,7 +150,7 @@ describe('loadPresets', () => {
           ],
         ],
       },
-    } as LoadContext;
+    } as Partial<LoadContext>;
     const presets = loadPresets(context);
     expect(presets).toMatchInlineSnapshot(`
       Object {
diff --git a/packages/docusaurus/src/server/presets/index.ts b/packages/docusaurus/src/server/presets/index.ts
index d74d1a2da7..2c3693fe92 100644
--- a/packages/docusaurus/src/server/presets/index.ts
+++ b/packages/docusaurus/src/server/presets/index.ts
@@ -7,15 +7,20 @@
 
 import importFresh from 'import-fresh';
 import _ from 'lodash';
-import {LoadContext, PluginConfig, Preset, PresetConfig} from '../types';
+import {
+  LoadContext,
+  PluginConfig,
+  Preset,
+  PresetConfig,
+} from '@docusaurus/types';
 
 export function loadPresets(
-  context: LoadContext,
+  context: Partial<LoadContext>,
 ): {
   plugins: PluginConfig[];
   themes: PluginConfig[];
 } {
-  const presets: PresetConfig[] = context.siteConfig.presets || [];
+  const presets: PresetConfig[] = (context.siteConfig || {}).presets || [];
   const unflatPlugins: (PluginConfig[])[] = [];
   const unflatThemes: (PluginConfig[])[] = [];
 
diff --git a/packages/docusaurus/src/server/routes.ts b/packages/docusaurus/src/server/routes.ts
index 98dd941459..f9bf0ce090 100644
--- a/packages/docusaurus/src/server/routes.ts
+++ b/packages/docusaurus/src/server/routes.ts
@@ -8,7 +8,12 @@
 import {genChunkName} from '@docusaurus/utils';
 import _ from 'lodash';
 import {stringify} from 'querystring';
-import {ChunkRegistry, Module, RouteConfig, RouteModule} from './types';
+import {
+  ChunkRegistry,
+  Module,
+  RouteConfig,
+  RouteModule,
+} from '@docusaurus/types';
 
 function getModulePath(target: Module): string {
   if (typeof target === 'string') {
diff --git a/packages/docusaurus/src/server/themes/alias.ts b/packages/docusaurus/src/server/themes/alias.ts
index ade27a3a6f..c473d3dc5f 100644
--- a/packages/docusaurus/src/server/themes/alias.ts
+++ b/packages/docusaurus/src/server/themes/alias.ts
@@ -9,7 +9,7 @@ import globby from 'globby';
 import fs from 'fs-extra';
 import path from 'path';
 import {fileToPath, posixPath, normalizeUrl} from '@docusaurus/utils';
-import {ThemeAlias} from '../types';
+import {ThemeAlias} from '@docusaurus/types';
 
 export function themeAlias(themePath: string): ThemeAlias {
   if (!fs.pathExistsSync(themePath)) {
diff --git a/packages/docusaurus/src/server/themes/index.ts b/packages/docusaurus/src/server/themes/index.ts
index 4ff55d4965..4734a16679 100644
--- a/packages/docusaurus/src/server/themes/index.ts
+++ b/packages/docusaurus/src/server/themes/index.ts
@@ -5,7 +5,7 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-import {ThemeAlias} from '../types';
+import {ThemeAlias} from '@docusaurus/types';
 import {themeAlias} from './alias';
 
 export function loadThemeAlias(themePaths: string[]): ThemeAlias {
diff --git a/packages/docusaurus/src/webpack/base.ts b/packages/docusaurus/src/webpack/base.ts
index fa6c6450bc..43dd45d7ea 100644
--- a/packages/docusaurus/src/webpack/base.ts
+++ b/packages/docusaurus/src/webpack/base.ts
@@ -12,7 +12,7 @@ import path from 'path';
 import TerserPlugin from 'terser-webpack-plugin';
 import {Configuration, Loader} from 'webpack';
 
-import {Props} from '../server/types';
+import {Props} from '@docusaurus/types';
 import {getBabelLoader, getCacheLoader, getStyleLoaders} from './utils';
 
 const CSS_REGEX = /\.css$/;
diff --git a/packages/docusaurus/src/webpack/client.ts b/packages/docusaurus/src/webpack/client.ts
index dc2e5c6e37..4b937c2122 100644
--- a/packages/docusaurus/src/webpack/client.ts
+++ b/packages/docusaurus/src/webpack/client.ts
@@ -9,7 +9,7 @@ import {Configuration} from 'webpack';
 import merge from 'webpack-merge';
 import WebpackNiceLog from 'webpack-nicelog';
 
-import {Props} from '../server/types';
+import {Props} from '@docusaurus/types';
 import {createBaseConfig} from './base';
 import ChunkManifestPlugin from './plugins/ChunkManifestPlugin';
 
diff --git a/packages/docusaurus/src/webpack/server.ts b/packages/docusaurus/src/webpack/server.ts
index cd7944330a..aa2c872cce 100644
--- a/packages/docusaurus/src/webpack/server.ts
+++ b/packages/docusaurus/src/webpack/server.ts
@@ -11,7 +11,7 @@ import {Configuration} from 'webpack';
 import merge from 'webpack-merge';
 import WebpackNiceLog from 'webpack-nicelog';
 
-import {Props} from '../server/types';
+import {Props} from '@docusaurus/types';
 import {createBaseConfig} from './base';
 import WaitPlugin from './plugins/WaitPlugin';