diff --git a/packages/docusaurus-plugin-content-blog/src/index.js b/packages/docusaurus-plugin-content-blog/src/index.js
index 827c18a56c..dceb8cd73c 100644
--- a/packages/docusaurus-plugin-content-blog/src/index.js
+++ b/packages/docusaurus-plugin-content-blog/src/index.js
@@ -156,24 +156,12 @@ class DocusaurusPluginContentBlog {
     );
   }
 
+  getThemePath() {
+    return path.resolve(__dirname, './theme');
+  }
+
   configureWebpack(config, isServer, {getBabelLoader, getCacheLoader}) {
     return {
-      resolve: {
-        alias: {
-          '@theme/BlogListPage': path.resolve(
-            __dirname,
-            './theme/BlogListPage',
-          ),
-          '@theme/BlogPostItem': path.resolve(
-            __dirname,
-            './theme/BlogPostItem',
-          ),
-          '@theme/BlogPostPage': path.resolve(
-            __dirname,
-            './theme/BlogPostPage',
-          ),
-        },
-      },
       module: {
         rules: [
           {
diff --git a/packages/docusaurus-plugin-content-docs/src/index.js b/packages/docusaurus-plugin-content-docs/src/index.js
index e4f457dd41..ea2b4b482e 100644
--- a/packages/docusaurus-plugin-content-docs/src/index.js
+++ b/packages/docusaurus-plugin-content-docs/src/index.js
@@ -151,19 +151,12 @@ class DocusaurusPluginContentDocs {
     });
   }
 
+  getThemePath() {
+    return path.resolve(__dirname, './theme');
+  }
+
   configureWebpack(config, isServer, {getBabelLoader, getCacheLoader}) {
     return {
-      resolve: {
-        alias: {
-          '@theme/DocItem': path.resolve(__dirname, './theme/DocItem'),
-          '@theme/DocPage': path.resolve(__dirname, './theme/DocPage'),
-          '@theme/DocPaginator': path.resolve(
-            __dirname,
-            './theme/DocPaginator',
-          ),
-          '@theme/DocSidebar': path.resolve(__dirname, './theme/DocSidebar'),
-        },
-      },
       module: {
         rules: [
           {
diff --git a/packages/docusaurus-theme-classic/src/index.js b/packages/docusaurus-theme-classic/src/index.js
index 1f3f3d371d..9fafacab35 100644
--- a/packages/docusaurus-theme-classic/src/index.js
+++ b/packages/docusaurus-theme-classic/src/index.js
@@ -19,18 +19,8 @@ class DocusaurusThemeDefault {
     return 'docusaurus-theme-classic';
   }
 
-  configureWebpack() {
-    return {
-      resolve: {
-        alias: {
-          '@theme/Footer': path.resolve(__dirname, './theme/Footer'),
-          '@theme/Layout': path.resolve(__dirname, './theme/Layout'),
-          '@theme/Navbar': path.resolve(__dirname, './theme/Navbar'),
-          '@theme/NotFound': path.resolve(__dirname, './theme/NotFound'),
-          '@theme/Search': path.resolve(__dirname, './theme/Search'),
-        },
-      },
-    };
+  getThemePath() {
+    return path.resolve(__dirname, './theme');
   }
 }
 
diff --git a/packages/docusaurus/bin/docusaurus.js b/packages/docusaurus/bin/docusaurus.js
index 4bc1e0d27d..ccd565f4d4 100755
--- a/packages/docusaurus/bin/docusaurus.js
+++ b/packages/docusaurus/bin/docusaurus.js
@@ -12,7 +12,7 @@ const envinfo = require('envinfo');
 const semver = require('semver');
 const path = require('path');
 const program = require('commander');
-const {build, eject, init, deploy, start} = require('../lib');
+const {build, swizzle, init, deploy, start} = require('../lib');
 const requiredVersion = require('../package.json').engines.node;
 
 if (!semver.satisfies(process.version, requiredVersion)) {
@@ -55,10 +55,10 @@ program
   });
 
 program
-  .command('eject [siteDir]')
-  .description('copy the default theme into website folder for customization.')
-  .action((siteDir = '.') => {
-    wrapCommand(eject)(path.resolve(siteDir));
+  .command('swizzle <themeName> [componentName] [siteDir]')
+  .description('Copy the theme files into website folder for customization.')
+  .action((themeName, componentName, siteDir = '.') => {
+    wrapCommand(swizzle)(path.resolve(siteDir), themeName, componentName);
   });
 
 program
diff --git a/packages/docusaurus/lib/commands/eject.js b/packages/docusaurus/lib/commands/eject.js
deleted file mode 100644
index fb082260db..0000000000
--- a/packages/docusaurus/lib/commands/eject.js
+++ /dev/null
@@ -1,23 +0,0 @@
-/**
- * Copyright (c) 2017-present, Facebook, Inc.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
-const fs = require('fs-extra');
-const chalk = require('chalk');
-const path = require('path');
-
-module.exports = async function eject(siteDir) {
-  const defaultTheme = path.resolve(__dirname, '..', 'default-theme');
-  const customTheme = path.resolve(siteDir, 'theme');
-  await fs.copy(defaultTheme, customTheme);
-
-  const relativeDir = path.relative(process.cwd(), customTheme);
-  console.log(
-    `\n${chalk.green('Success!')} Copied default theme files to ${chalk.cyan(
-      relativeDir,
-    )}.\n`,
-  );
-};
diff --git a/packages/docusaurus/lib/commands/swizzle.js b/packages/docusaurus/lib/commands/swizzle.js
new file mode 100644
index 0000000000..9c1489b775
--- /dev/null
+++ b/packages/docusaurus/lib/commands/swizzle.js
@@ -0,0 +1,36 @@
+/**
+ * Copyright (c) 2017-present, Facebook, Inc.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+const fs = require('fs-extra');
+const chalk = require('chalk');
+const path = require('path');
+const importFresh = require('import-fresh');
+
+module.exports = async function swizzle(siteDir, themeName, componentName) {
+  const Plugin = importFresh(themeName);
+  const context = {siteDir};
+  const PluginInstance = new Plugin(context);
+  let fromPath = PluginInstance.getThemePath();
+
+  if (fromPath) {
+    let toPath = path.resolve(siteDir, 'theme');
+    if (componentName) {
+      fromPath = path.join(fromPath, componentName);
+      toPath = path.join(toPath, componentName);
+    }
+    await fs.copy(fromPath, toPath);
+
+    const relativeDir = path.relative(process.cwd(), toPath);
+    const fromMsg = chalk.blue(
+      componentName ? `${themeName}/${componentName}` : themeName,
+    );
+    const toMsg = chalk.cyan(relativeDir);
+    console.log(
+      `\n${chalk.green('Success!')} Copied ${fromMsg} to ${toMsg}.\n`,
+    );
+  }
+};
diff --git a/packages/docusaurus/lib/index.js b/packages/docusaurus/lib/index.js
index 60c36dc6d5..6b2018f0cb 100644
--- a/packages/docusaurus/lib/index.js
+++ b/packages/docusaurus/lib/index.js
@@ -8,12 +8,12 @@
 const build = require('./commands/build');
 const init = require('./commands/init');
 const start = require('./commands/start');
-const eject = require('./commands/eject');
+const swizzle = require('./commands/swizzle');
 const deploy = require('./commands/deploy');
 
 module.exports = {
   build,
-  eject,
+  swizzle,
   init,
   start,
   deploy,
diff --git a/packages/docusaurus/lib/server/index.js b/packages/docusaurus/lib/server/index.js
index f3a2c8d61f..244e4b958c 100644
--- a/packages/docusaurus/lib/server/index.js
+++ b/packages/docusaurus/lib/server/index.js
@@ -51,18 +51,42 @@ module.exports = async function load(siteDir, cliOptions = {}) {
   const outDir = path.resolve(siteDir, 'build');
   const {baseUrl} = siteConfig;
 
-  // Resolve custom theme override aliases.
-  const themeAliases = await loadTheme(siteDir);
-  // Make a fake plugin to resolve user's theme overrides.
-  if (themeAliases != null) {
-    plugins.push({
-      configureWebpack: () => ({
-        resolve: {
-          alias: themeAliases,
-        },
-      }),
-    });
-  }
+  // Default theme components that are essential and must exist in a Docusaurus app
+  // These can be overriden in plugins/ through component swizzling.
+  // However, we alias it here first as a fallback.
+  const themeFallback = path.resolve(__dirname, '../client/theme-fallback');
+  let themeAliases = await loadTheme(themeFallback);
+
+  // create theme alias from plugins
+  await Promise.all(
+    plugins.map(async plugin => {
+      if (!plugin.getThemePath) {
+        return;
+      }
+      const aliases = await loadTheme(plugin.getThemePath());
+      themeAliases = {
+        ...themeAliases,
+        ...aliases,
+      };
+    }),
+  );
+
+  // user's own theme alias override. Highest priority
+  const themePath = path.resolve(siteDir, 'theme');
+  const aliases = await loadTheme(themePath);
+  themeAliases = {
+    ...themeAliases,
+    ...aliases,
+  };
+
+  // Make a fake plugin to resolve alias theme.
+  plugins.push({
+    configureWebpack: () => ({
+      resolve: {
+        alias: themeAliases,
+      },
+    }),
+  });
 
   // Routing
   const {
diff --git a/packages/docusaurus/lib/server/load/theme.js b/packages/docusaurus/lib/server/load/theme.js
index 010feb35fb..426dcd9d0b 100644
--- a/packages/docusaurus/lib/server/load/theme.js
+++ b/packages/docusaurus/lib/server/load/theme.js
@@ -10,8 +10,7 @@ const fs = require('fs-extra');
 const path = require('path');
 const {fileToPath, posixPath, normalizeUrl} = require('@docusaurus/utils');
 
-module.exports = async function loadTheme(siteDir) {
-  const themePath = path.resolve(siteDir, 'theme');
+module.exports = async function loadTheme(themePath) {
   if (!fs.existsSync(themePath)) {
     return null;
   }
diff --git a/packages/docusaurus/lib/webpack/base.js b/packages/docusaurus/lib/webpack/base.js
index f579f67b2e..5f93ea994f 100644
--- a/packages/docusaurus/lib/webpack/base.js
+++ b/packages/docusaurus/lib/webpack/base.js
@@ -25,7 +25,6 @@ module.exports = function createBaseConfig(props, isServer) {
   } = props;
 
   const isProd = process.env.NODE_ENV === 'production';
-  const themeFallback = path.resolve(__dirname, '../client/theme-fallback');
   return {
     mode: isProd ? 'production' : 'development',
     output: {
@@ -44,11 +43,6 @@ module.exports = function createBaseConfig(props, isServer) {
       alias: {
         // https://stackoverflow.com/a/55433680/6072730
         ejs: 'ejs/ejs.min.js',
-        // These alias can be overriden in plugins. However, these components are essential
-        // (e.g: react-loadable requires Loading component) so we alias it here first as fallback.
-        '@theme/Layout': path.join(themeFallback, 'Layout'),
-        '@theme/Loading': path.join(themeFallback, 'Loading'),
-        '@theme/NotFound': path.join(themeFallback, 'NotFound'),
         '@site': siteDir,
         '@generated': generatedFilesDir,
         '@docusaurus': path.resolve(__dirname, '../client/exports'),
diff --git a/website/package.json b/website/package.json
index 4949a521c3..f4d2447700 100644
--- a/website/package.json
+++ b/website/package.json
@@ -5,7 +5,7 @@
   "scripts": {
     "start": "docusaurus start",
     "build": "docusaurus build",
-    "eject": "docusaurus eject",
+    "swizzle": "docusaurus swizzle",
     "deploy": "docusaurus deploy"
   },
   "dependencies": {