diff --git a/packages/cli/package.json b/packages/cli/package.json
index 8d54bb3ab..7ed797ed2 100644
--- a/packages/cli/package.json
+++ b/packages/cli/package.json
@@ -29,9 +29,9 @@
     "@react-native-community/cli-tools": "^2.8.3",
     "@react-native-community/cli-types": "^3.0.0-alpha.2",
     "@types/mkdirp": "^0.5.2",
+    "@types/node-notifier": "^5.4.0",
     "@types/semver": "^6.0.2",
     "@types/ws": "^6.0.3",
-    "@types/node-notifier": "^5.4.0",
     "chalk": "^2.4.2",
     "command-exists": "^1.2.8",
     "commander": "^2.19.0",
@@ -72,11 +72,14 @@
   },
   "devDependencies": {
     "@types/command-exists": "^1.2.0",
+    "@types/compression": "^1.0.1",
     "@types/cosmiconfig": "^5.0.3",
+    "@types/errorhandler": "^0.0.32",
     "@types/graceful-fs": "^4.1.3",
     "@types/hapi__joi": "^15.0.4",
     "@types/minimist": "^1.2.0",
     "@types/mkdirp": "^0.5.2",
+    "@types/morgan": "^1.7.37",
     "@types/semver": "^6.0.2",
     "@types/wcwidth": "^1.0.0",
     "slash": "^3.0.0",
diff --git a/packages/cli/src/commands/doctor/healthchecks/androidSDK.ts b/packages/cli/src/commands/doctor/healthchecks/androidSDK.ts
index a53b56487..e4d8fcec6 100644
--- a/packages/cli/src/commands/doctor/healthchecks/androidSDK.ts
+++ b/packages/cli/src/commands/doctor/healthchecks/androidSDK.ts
@@ -20,7 +20,6 @@ export default {
     // See the PR: https://github.com/tabrindle/envinfo/pull/119
     if (sdks === 'Not Found' && process.platform !== 'darwin') {
       try {
-        // $FlowFixMe bad execa types
         const {stdout} = await execa(
           process.env.ANDROID_HOME
             ? `${process.env.ANDROID_HOME}/tools/bin/sdkmanager`
diff --git a/packages/cli/src/commands/link/__tests__/link-test.ts b/packages/cli/src/commands/link/__tests__/link.test.ts
similarity index 100%
rename from packages/cli/src/commands/link/__tests__/link-test.ts
rename to packages/cli/src/commands/link/__tests__/link.test.ts
diff --git a/packages/cli/src/commands/link/__tests__/makeHook-test.ts b/packages/cli/src/commands/link/__tests__/makeHook.test.ts
similarity index 100%
rename from packages/cli/src/commands/link/__tests__/makeHook-test.ts
rename to packages/cli/src/commands/link/__tests__/makeHook.test.ts
diff --git a/packages/cli/src/commands/server/messageSocket.ts b/packages/cli/src/commands/server/messageSocket.ts
index 911622900..c3bd6603b 100644
--- a/packages/cli/src/commands/server/messageSocket.ts
+++ b/packages/cli/src/commands/server/messageSocket.ts
@@ -250,7 +250,8 @@ function attachToServer(server: Server, path: string) {
   });
 
   return {
-    broadcast: (method: string, params: Record<string, any>) => {
+    isDebuggerConnected: () => true,
+    broadcast: (method: string, params?: Record<string, any>) => {
       handleSendBroadcast(null, {method, params});
     },
   };
diff --git a/packages/cli/src/commands/server/middleware/MiddlewareManager.js b/packages/cli/src/commands/server/middleware/MiddlewareManager.ts
similarity index 87%
rename from packages/cli/src/commands/server/middleware/MiddlewareManager.js
rename to packages/cli/src/commands/server/middleware/MiddlewareManager.ts
index bf429fb51..018e8fcf5 100644
--- a/packages/cli/src/commands/server/middleware/MiddlewareManager.js
+++ b/packages/cli/src/commands/server/middleware/MiddlewareManager.ts
@@ -3,9 +3,6 @@
  *
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
- *
- * @strict
- * @flow
  */
 
 import compression from 'compression';
@@ -26,19 +23,18 @@ import systraceProfileMiddleware from './systraceProfileMiddleware';
 import getDevToolsMiddleware from './getDevToolsMiddleware';
 
 type Options = {
-  +watchFolders: $ReadOnlyArray<string>,
-  +host?: string,
+  host?: string;
+  watchFolders: Array<string>;
+  port: number;
 };
 
 type WebSocketProxy = {
-  server: WebSocketServer,
-  isDebuggerConnected: () => boolean,
+  server?: WebSocketServer;
+  isDebuggerConnected: () => boolean;
 };
 
-type Connect = $Call<connect>;
-
 export default class MiddlewareManager {
-  app: Connect;
+  app: connect.Server;
 
   options: Options;
 
@@ -49,6 +45,7 @@ export default class MiddlewareManager {
     this.app = connect()
       .use(getSecurityHeadersMiddleware)
       .use(loadRawBodyMiddleware)
+      // @ts-ignore compression and connect types mismatch
       .use(compression())
       .use('/debugger-ui', serveStatic(debuggerUIFolder))
       .use(openStackFrameInEditorMiddleware(this.options))
@@ -61,6 +58,7 @@ export default class MiddlewareManager {
   }
 
   serveStatic(folder: string) {
+    // @ts-ignore serveStatic and connect types mismatch
     this.app.use(serveStatic(folder));
   }
 
diff --git a/packages/cli/src/commands/server/middleware/copyToClipBoardMiddleware.js b/packages/cli/src/commands/server/middleware/copyToClipBoardMiddleware.ts
similarity index 70%
rename from packages/cli/src/commands/server/middleware/copyToClipBoardMiddleware.js
rename to packages/cli/src/commands/server/middleware/copyToClipBoardMiddleware.ts
index ab369efdb..d7665c1f5 100644
--- a/packages/cli/src/commands/server/middleware/copyToClipBoardMiddleware.js
+++ b/packages/cli/src/commands/server/middleware/copyToClipBoardMiddleware.ts
@@ -4,9 +4,8 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @format
  */
-
+import http from 'http';
 import copyToClipBoard from '../copyToClipBoard';
 import {logger} from '@react-native-community/cli-tools';
 
@@ -14,9 +13,15 @@ import {logger} from '@react-native-community/cli-tools';
  * Handle the request from JS to copy contents onto host system clipboard.
  * This is only supported on Mac for now.
  */
-export default function copyMiddleware(req, res, next) {
+export default function copyMiddleware(
+  req: http.IncomingMessage,
+  res: http.ServerResponse,
+  next: (err?: any) => void,
+) {
   if (req.url === '/copy-to-clipboard') {
-    const ret = copyToClipBoard(req.rawBody);
+    const ret = copyToClipBoard(
+      (req as http.IncomingMessage & {rawBody: string}).rawBody,
+    );
     if (!ret) {
       logger.warn('Copy button is not supported on this platform!');
     }
diff --git a/packages/cli/src/commands/server/middleware/getDevToolsMiddleware.js b/packages/cli/src/commands/server/middleware/getDevToolsMiddleware.ts
similarity index 63%
rename from packages/cli/src/commands/server/middleware/getDevToolsMiddleware.js
rename to packages/cli/src/commands/server/middleware/getDevToolsMiddleware.ts
index fad5a8728..9f13b2ba5 100644
--- a/packages/cli/src/commands/server/middleware/getDevToolsMiddleware.js
+++ b/packages/cli/src/commands/server/middleware/getDevToolsMiddleware.ts
@@ -3,25 +3,29 @@
  *
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
- *
- * @format
  */
+import http from 'http';
 import {logger} from '@react-native-community/cli-tools';
 import {exec} from 'child_process';
 import launchDebugger from '../launchDebugger';
 
-function launchDefaultDebugger(port, args = '') {
+function launchDefaultDebugger(port: number, args = '') {
   const debuggerURL = `http://localhost:${port}/debugger-ui${args}`;
   logger.info('Launching Dev Tools...');
   launchDebugger(debuggerURL);
 }
 
-function escapePath(pathname) {
+function escapePath(pathname: string) {
   // " Can escape paths with spaces in OS X, Windows, and *nix
   return `"${pathname}"`;
 }
 
-function launchDevTools({port, watchFolders}, isDebuggerConnected) {
+type LaunchDevToolsOptions = {port: number; watchFolders: Array<string>};
+
+function launchDevTools(
+  {port, watchFolders}: LaunchDevToolsOptions,
+  isDebuggerConnected: () => boolean,
+) {
   // Explicit config always wins
   const customDebugger = process.env.REACT_DEBUGGER;
   if (customDebugger) {
@@ -32,19 +36,32 @@ function launchDevTools({port, watchFolders}, isDebuggerConnected) {
   }
 }
 
-function startCustomDebugger({watchFolders, customDebugger}) {
+function startCustomDebugger({
+  watchFolders,
+  customDebugger,
+}: {
+  watchFolders: Array<string>;
+  customDebugger: string;
+}) {
   const folders = watchFolders.map(escapePath).join(' ');
   const command = `${customDebugger} ${folders}`;
   logger.info('Starting custom debugger by executing:', command);
-  exec(command, function(error, stdout, stderr) {
+  exec(command, function(error) {
     if (error !== null) {
-      logger.error('Error while starting custom debugger:', error);
+      logger.error('Error while starting custom debugger:', error.stack || '');
     }
   });
 }
 
-export default function getDevToolsMiddleware(options, isDebuggerConnected) {
-  return function devToolsMiddleware(req, res, next) {
+export default function getDevToolsMiddleware(
+  options: LaunchDevToolsOptions,
+  isDebuggerConnected: () => boolean,
+) {
+  return function devToolsMiddleware(
+    req: http.IncomingMessage,
+    res: http.ServerResponse,
+    next: (err?: any) => void,
+  ) {
     if (req.url === '/launch-js-devtools') {
       launchDevTools(options, isDebuggerConnected);
       res.end('OK');
diff --git a/packages/cli/src/commands/server/middleware/getSecurityHeadersMiddleware.js b/packages/cli/src/commands/server/middleware/getSecurityHeadersMiddleware.ts
similarity index 74%
rename from packages/cli/src/commands/server/middleware/getSecurityHeadersMiddleware.js
rename to packages/cli/src/commands/server/middleware/getSecurityHeadersMiddleware.ts
index 38de1c232..498ce8b6f 100644
--- a/packages/cli/src/commands/server/middleware/getSecurityHeadersMiddleware.js
+++ b/packages/cli/src/commands/server/middleware/getSecurityHeadersMiddleware.ts
@@ -3,12 +3,15 @@
  *
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
- *
- * @strict
- * @format
  */
+import http from 'http';
 
-export default function getSecurityHeadersMiddleware(req, res, next) {
+export default function getSecurityHeadersMiddleware(
+  req: http.IncomingMessage,
+  res: http.ServerResponse,
+  next: (err?: any) => void,
+) {
+  // @ts-ignore Property 'client' does not exist on type 'IncomingMessage', verify
   const address = req.client.server.address();
 
   // Block any cross origin request.
diff --git a/packages/cli/src/commands/server/middleware/indexPage.js b/packages/cli/src/commands/server/middleware/indexPage.ts
similarity index 71%
rename from packages/cli/src/commands/server/middleware/indexPage.js
rename to packages/cli/src/commands/server/middleware/indexPage.ts
index 28a1d48b8..403c8e922 100644
--- a/packages/cli/src/commands/server/middleware/indexPage.js
+++ b/packages/cli/src/commands/server/middleware/indexPage.ts
@@ -3,14 +3,16 @@
  *
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
- *
- * @format
  */
-
+import http from 'http';
 import fs from 'fs';
 import path from 'path';
 
-export default function indexPageMiddleware(req, res, next) {
+export default function indexPageMiddleware(
+  req: http.IncomingMessage,
+  res: http.ServerResponse,
+  next: (err?: any) => void,
+) {
   if (req.url === '/') {
     res.setHeader('Content-Type', 'text/html');
     res.end(fs.readFileSync(path.join(__dirname, 'index.html')));
diff --git a/packages/cli/src/commands/server/middleware/loadRawBodyMiddleware.js b/packages/cli/src/commands/server/middleware/loadRawBodyMiddleware.js
deleted file mode 100644
index d65533986..000000000
--- a/packages/cli/src/commands/server/middleware/loadRawBodyMiddleware.js
+++ /dev/null
@@ -1,21 +0,0 @@
-/**
- * Copyright (c) Facebook, Inc. and its affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- *
- * @format
- */
-
-export default function rawBodyMiddleware(req, res, next) {
-  req.rawBody = '';
-  req.setEncoding('utf8');
-
-  req.on('data', chunk => {
-    req.rawBody += chunk;
-  });
-
-  req.on('end', () => {
-    next();
-  });
-}
diff --git a/packages/cli/src/commands/server/middleware/loadRawBodyMiddleware.ts b/packages/cli/src/commands/server/middleware/loadRawBodyMiddleware.ts
new file mode 100644
index 000000000..2a9746387
--- /dev/null
+++ b/packages/cli/src/commands/server/middleware/loadRawBodyMiddleware.ts
@@ -0,0 +1,24 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+import http from 'http';
+
+export default function rawBodyMiddleware(
+  req: http.IncomingMessage,
+  _res: http.ServerResponse,
+  next: (err?: any) => void,
+) {
+  (req as http.IncomingMessage & {rawBody: string}).rawBody = '';
+  req.setEncoding('utf8');
+
+  req.on('data', (chunk: string) => {
+    (req as http.IncomingMessage & {rawBody: string}).rawBody += chunk;
+  });
+
+  req.on('end', () => {
+    next();
+  });
+}
diff --git a/packages/cli/src/commands/server/middleware/openStackFrameInEditorMiddleware.js b/packages/cli/src/commands/server/middleware/openStackFrameInEditorMiddleware.ts
similarity index 61%
rename from packages/cli/src/commands/server/middleware/openStackFrameInEditorMiddleware.js
rename to packages/cli/src/commands/server/middleware/openStackFrameInEditorMiddleware.ts
index 676ddd49a..6e6b89b3f 100644
--- a/packages/cli/src/commands/server/middleware/openStackFrameInEditorMiddleware.js
+++ b/packages/cli/src/commands/server/middleware/openStackFrameInEditorMiddleware.ts
@@ -3,14 +3,20 @@
  *
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
- *
- * @format
  */
-
+import http from 'http';
 import launchEditor from '../launchEditor';
 
-export default function getOpenStackFrameInEditorMiddleware({watchFolders}) {
-  return (req, res, next) => {
+export default function getOpenStackFrameInEditorMiddleware({
+  watchFolders,
+}: {
+  watchFolders: Array<string>;
+}) {
+  return (
+    req: http.IncomingMessage & {rawBody: string},
+    res: http.ServerResponse,
+    next: (err?: any) => void,
+  ) => {
     if (req.url === '/open-stack-frame') {
       const frame = JSON.parse(req.rawBody);
       launchEditor(frame.file, frame.lineNumber, watchFolders);
diff --git a/packages/cli/src/commands/server/middleware/openURLMiddleware.js b/packages/cli/src/commands/server/middleware/openURLMiddleware.ts
similarity index 76%
rename from packages/cli/src/commands/server/middleware/openURLMiddleware.js
rename to packages/cli/src/commands/server/middleware/openURLMiddleware.ts
index 6f468c0a3..1a3a4525f 100644
--- a/packages/cli/src/commands/server/middleware/openURLMiddleware.js
+++ b/packages/cli/src/commands/server/middleware/openURLMiddleware.ts
@@ -3,17 +3,19 @@
  *
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
- *
- * @format
  */
-
+import http from 'http';
 import launchDefaultBrowser from '../launchDefaultBrowser';
 import {logger} from '@react-native-community/cli-tools';
 
 /**
  * Handle request from JS to open an arbitrary URL in Chrome
  */
-export default function openURLMiddleware(req, res, next) {
+export default function openURLMiddleware(
+  req: http.IncomingMessage & {rawBody: string},
+  res: http.ServerResponse,
+  next: (err?: any) => void,
+) {
   if (req.url === '/open-url') {
     const {url} = JSON.parse(req.rawBody);
     logger.info(`Opening ${url}...`);
diff --git a/packages/cli/src/commands/server/middleware/statusPageMiddleware.js b/packages/cli/src/commands/server/middleware/statusPageMiddleware.ts
similarity index 72%
rename from packages/cli/src/commands/server/middleware/statusPageMiddleware.js
rename to packages/cli/src/commands/server/middleware/statusPageMiddleware.ts
index 183ecc0f7..215bf5c3c 100644
--- a/packages/cli/src/commands/server/middleware/statusPageMiddleware.js
+++ b/packages/cli/src/commands/server/middleware/statusPageMiddleware.ts
@@ -3,15 +3,18 @@
  *
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
- *
- * @format
  */
+import http from 'http';
 
 /**
  * Status page so that anyone who needs to can verify that the packager is
  * running on 8081 and not another program / service.
  */
-export default function statusPageMiddleware(req, res, next) {
+export default function statusPageMiddleware(
+  req: http.IncomingMessage,
+  res: http.ServerResponse,
+  next: (err?: any) => void,
+) {
   if (req.url === '/status') {
     res.end('packager-status:running');
   } else {
diff --git a/packages/cli/src/commands/server/middleware/systraceProfileMiddleware.js b/packages/cli/src/commands/server/middleware/systraceProfileMiddleware.ts
similarity index 81%
rename from packages/cli/src/commands/server/middleware/systraceProfileMiddleware.js
rename to packages/cli/src/commands/server/middleware/systraceProfileMiddleware.ts
index 0a54d0687..35557aa81 100644
--- a/packages/cli/src/commands/server/middleware/systraceProfileMiddleware.js
+++ b/packages/cli/src/commands/server/middleware/systraceProfileMiddleware.ts
@@ -3,14 +3,16 @@
  *
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
- *
- * @format
  */
-
+import http from 'http';
 import fs from 'fs';
 import {logger} from '@react-native-community/cli-tools';
 
-export default function systraceProfileMiddleware(req, res, next) {
+export default function systraceProfileMiddleware(
+  req: http.IncomingMessage & {rawBody: string},
+  res: http.ServerResponse,
+  next: (err?: any) => void,
+) {
   if (req.url !== '/systrace') {
     next();
     return;
diff --git a/packages/cli/src/commands/server/middleware/unless.js b/packages/cli/src/commands/server/middleware/unless.js
deleted file mode 100644
index 77f11d75e..000000000
--- a/packages/cli/src/commands/server/middleware/unless.js
+++ /dev/null
@@ -1,16 +0,0 @@
-/**
- * Copyright (c) Facebook, Inc. and its affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- *
- * @format
- */
-
-export default (url, middleware) => (req, res, next) => {
-  if (req.url === url || req.url.startsWith(`${url}/`)) {
-    middleware(req, res, next);
-  } else {
-    next();
-  }
-};
diff --git a/packages/cli/src/commands/server/runServer.js b/packages/cli/src/commands/server/runServer.ts
similarity index 75%
rename from packages/cli/src/commands/server/runServer.js
rename to packages/cli/src/commands/server/runServer.ts
index e2039f31f..968297ebe 100644
--- a/packages/cli/src/commands/server/runServer.js
+++ b/packages/cli/src/commands/server/runServer.ts
@@ -3,48 +3,44 @@
  *
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
- *
- * @flow
  */
 
+// @ts-ignore untyped metro
 import Metro from 'metro';
+// @ts-ignore untyped metro
 import {Terminal} from 'metro-core';
 import morgan from 'morgan';
 import path from 'path';
 import {logger} from '@react-native-community/cli-tools';
-import type {ConfigT} from 'types';
-// $FlowFixMe - converted to TS
+import {Config} from '@react-native-community/cli-types';
 import messageSocket from './messageSocket';
-// $FlowFixMe - converted to TS
 import webSocketProxy from './webSocketProxy';
 import MiddlewareManager from './middleware/MiddlewareManager';
-// $FlowFixMe - converted to TS
 import loadMetroConfig from '../../tools/loadMetroConfig';
-// $FlowFixMe - converted to TS
 import releaseChecker from '../../tools/releaseChecker';
 
-export type Args = {|
-  assetPlugins?: string[],
-  cert?: string,
-  customLogReporterPath?: string,
-  host?: string,
-  https?: boolean,
-  maxWorkers?: number,
-  key?: string,
-  platforms?: string[],
-  port?: number,
-  resetCache?: boolean,
-  sourceExts?: string[],
-  transformer?: string,
-  verbose?: boolean,
-  watchFolders?: string[],
-  config?: string,
-  projectRoot?: string,
-|};
-
-async function runServer(argv: Array<string>, ctx: ConfigT, args: Args) {
+export type Args = {
+  assetPlugins?: string[];
+  cert?: string;
+  customLogReporterPath?: string;
+  host?: string;
+  https?: boolean;
+  maxWorkers?: number;
+  key?: string;
+  platforms?: string[];
+  port?: number;
+  resetCache?: boolean;
+  sourceExts?: string[];
+  transformer?: string;
+  verbose?: boolean;
+  watchFolders?: string[];
+  config?: string;
+  projectRoot?: string;
+};
+
+async function runServer(_argv: Array<string>, ctx: Config, args: Args) {
   const terminal = new Terminal(process.stdout);
-  const ReporterImpl = getReporterImpl(args.customLogReporterPath || null);
+  const ReporterImpl = getReporterImpl(args.customLogReporterPath);
   const reporter = new ReporterImpl(terminal);
 
   const metroConfig = await loadMetroConfig(ctx, {
@@ -71,11 +67,14 @@ async function runServer(argv: Array<string>, ctx: ConfigT, args: Args) {
   });
 
   middlewareManager.getConnectInstance().use(
+    // @ts-ignore morgan and connect types mismatch
     morgan(
       'combined',
-      !logger.isVerbose() && {
-        skip: (req, res) => res.statusCode < 400,
-      },
+      !logger.isVerbose()
+        ? {
+            skip: (_req, res) => res.statusCode < 400,
+          }
+        : undefined,
     ),
   );
 
@@ -85,7 +84,7 @@ async function runServer(argv: Array<string>, ctx: ConfigT, args: Args) {
 
   const customEnhanceMiddleware = metroConfig.server.enhanceMiddleware;
 
-  metroConfig.server.enhanceMiddleware = (middleware, server) => {
+  metroConfig.server.enhanceMiddleware = (middleware: any, server: unknown) => {
     if (customEnhanceMiddleware) {
       middleware = customEnhanceMiddleware(middleware, server);
     }
@@ -109,10 +108,12 @@ async function runServer(argv: Array<string>, ctx: ConfigT, args: Args) {
   middlewareManager.attachDevToolsSocket(wsProxy);
   middlewareManager.attachDevToolsSocket(ms);
 
-  middlewareManager.getConnectInstance().use('/reload', (req, res) => {
-    ms.broadcast('reload', null);
-    res.end('OK');
-  });
+  middlewareManager
+    .getConnectInstance()
+    .use('/reload', (_req: unknown, res: any) => {
+      ms.broadcast('reload');
+      res.end('OK');
+    });
 
   // In Node 8, the default keep-alive for an HTTP connection is 5 seconds. In
   // early versions of Node 8, this was implemented in a buggy way which caused
@@ -129,8 +130,8 @@ async function runServer(argv: Array<string>, ctx: ConfigT, args: Args) {
   await releaseChecker(ctx.root);
 }
 
-function getReporterImpl(customLogReporterPath: ?string) {
-  if (customLogReporterPath == null) {
+function getReporterImpl(customLogReporterPath: string | void) {
+  if (customLogReporterPath === undefined) {
     return require('metro/src/lib/TerminalReporter');
   }
   try {
diff --git a/packages/cli/src/commands/server/server.js b/packages/cli/src/commands/server/server.ts
similarity index 99%
rename from packages/cli/src/commands/server/server.js
rename to packages/cli/src/commands/server/server.ts
index 42e120faf..d7c7b86ca 100644
--- a/packages/cli/src/commands/server/server.js
+++ b/packages/cli/src/commands/server/server.ts
@@ -4,8 +4,6 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @format
- * @flow
  */
 
 import path from 'path';
diff --git a/packages/cli/src/tools/config/__tests__/findDependencies-test.ts b/packages/cli/src/tools/config/__tests__/findDependencies-test.ts
index a0a8afaee..818643ca9 100644
--- a/packages/cli/src/tools/config/__tests__/findDependencies-test.ts
+++ b/packages/cli/src/tools/config/__tests__/findDependencies-test.ts
@@ -6,7 +6,7 @@ import findDependencies from '../findDependencies';
 import {
   cleanup,
   writeFiles,
-  getTempDirectory, // $FlowFixMe - converted to TS
+  getTempDirectory,
 } from '../../../../../../jest/helpers';
 
 jest.mock('../resolveNodeModuleDir');
diff --git a/packages/cli/src/tools/config/__tests__/index-test.ts b/packages/cli/src/tools/config/__tests__/index-test.ts
index e789bd890..015012c45 100644
--- a/packages/cli/src/tools/config/__tests__/index-test.ts
+++ b/packages/cli/src/tools/config/__tests__/index-test.ts
@@ -8,7 +8,7 @@ import {logger} from '@react-native-community/cli-tools';
 import {
   cleanup,
   writeFiles,
-  getTempDirectory, // $FlowFixMe - converted to TS
+  getTempDirectory,
 } from '../../../../../../jest/helpers';
 
 jest.mock('../resolveNodeModuleDir');
diff --git a/packages/cli/src/tools/config/index.ts b/packages/cli/src/tools/config/index.ts
index f0a5d1b2b..7420108b5 100644
--- a/packages/cli/src/tools/config/index.ts
+++ b/packages/cli/src/tools/config/index.ts
@@ -43,8 +43,6 @@ function getDependencyConfig(
               ? null
               : platformConfig.dependencyConfig(
                   root,
-                  /* $FlowFixMe - can't figure out which platform's dependency
-                 config to choose */
                   config.dependency.platforms[platform],
                 );
           return dependency;
diff --git a/packages/cli/src/tools/loadMetroConfig.ts b/packages/cli/src/tools/loadMetroConfig.ts
index b9c3426c2..7b82e592f 100644
--- a/packages/cli/src/tools/loadMetroConfig.ts
+++ b/packages/cli/src/tools/loadMetroConfig.ts
@@ -46,6 +46,7 @@ export interface MetroConfig {
   };
   server: {
     port: number;
+    enhanceMiddleware?: Function;
   };
   symbolicator: {
     customizeFrame: (frame: {file: string | null}) => {collapse: boolean};
@@ -53,6 +54,7 @@ export interface MetroConfig {
   transformer: {
     babelTransformerPath: string;
     assetRegistryPath: string;
+    assetPlugins?: Array<string>;
   };
   watchFolders: string[];
   reporter?: any;
diff --git a/yarn.lock b/yarn.lock
index dd6834730..da7c17a9e 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -2027,11 +2027,33 @@
   dependencies:
     "@babel/types" "^7.3.0"
 
+"@types/body-parser@*":
+  version "1.17.1"
+  resolved "https://registry.yarnpkg.com/@types/body-parser/-/body-parser-1.17.1.tgz#18fcf61768fb5c30ccc508c21d6fd2e8b3bf7897"
+  integrity sha512-RoX2EZjMiFMjZh9lmYrwgoP9RTpAjSHiJxdp4oidAQVO02T7HER3xj9UKue5534ULWeqVEkujhWcyvUce+d68w==
+  dependencies:
+    "@types/connect" "*"
+    "@types/node" "*"
+
 "@types/command-exists@^1.2.0":
   version "1.2.0"
   resolved "https://registry.yarnpkg.com/@types/command-exists/-/command-exists-1.2.0.tgz#d97e0ed10097090e4ab0367ed425b0312fad86f3"
   integrity sha512-ugsxEJfsCuqMLSuCD4PIJkp5Uk2z6TCMRCgYVuhRo5cYQY3+1xXTQkSlPtkpGHuvWMjS2KTeVQXxkXRACMbM6A==
 
+"@types/compression@^1.0.1":
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/@types/compression/-/compression-1.0.1.tgz#f3682a6b3ce2dbd4aece48547153ebc592281fa7"
+  integrity sha512-GuoIYzD70h+4JUqUabsm31FGqvpCYHGKcLtor7nQ/YvUyNX0o9SJZ9boFI5HjFfbOda5Oe/XOvNK6FES8Y/79w==
+  dependencies:
+    "@types/express" "*"
+
+"@types/connect@*":
+  version "3.4.32"
+  resolved "https://registry.yarnpkg.com/@types/connect/-/connect-3.4.32.tgz#aa0e9616b9435ccad02bc52b5b454ffc2c70ba28"
+  integrity sha512-4r8qa0quOvh7lGD0pre62CAb1oni1OO6ecJLGCezTmhQ8Fz50Arx9RUszryR8KlgK6avuSXvviL6yWyViQABOg==
+  dependencies:
+    "@types/node" "*"
+
 "@types/cosmiconfig@^5.0.3":
   version "5.0.3"
   resolved "https://registry.yarnpkg.com/@types/cosmiconfig/-/cosmiconfig-5.0.3.tgz#880644bb155d4038d3b752159684b777b0a159dd"
@@ -2039,6 +2061,13 @@
   dependencies:
     "@types/node" "*"
 
+"@types/errorhandler@^0.0.32":
+  version "0.0.32"
+  resolved "https://registry.yarnpkg.com/@types/errorhandler/-/errorhandler-0.0.32.tgz#387eca73957b481254baddc15d1d40f7fe7153c6"
+  integrity sha512-wC9CfwPMIzklPd5lEYC8HnQdlMC1PswlohWmEDMWlw+E/rMYuz5eSqKBc72Earb29KptKJrRl77qVRJzrZndww==
+  dependencies:
+    "@types/express" "*"
+
 "@types/events@*":
   version "3.0.0"
   resolved "https://registry.yarnpkg.com/@types/events/-/events-3.0.0.tgz#2862f3f58a9a7f7c3e78d79f130dd4d71c25c2a7"
@@ -2051,6 +2080,23 @@
   dependencies:
     "@types/node" "*"
 
+"@types/express-serve-static-core@*":
+  version "4.16.9"
+  resolved "https://registry.yarnpkg.com/@types/express-serve-static-core/-/express-serve-static-core-4.16.9.tgz#69e00643b0819b024bdede95ced3ff239bb54558"
+  integrity sha512-GqpaVWR0DM8FnRUJYKlWgyARoBUAVfRIeVDZQKOttLFp5SmhhF9YFIYeTPwMd/AXfxlP7xVO2dj1fGu0Q+krKQ==
+  dependencies:
+    "@types/node" "*"
+    "@types/range-parser" "*"
+
+"@types/express@*":
+  version "4.17.1"
+  resolved "https://registry.yarnpkg.com/@types/express/-/express-4.17.1.tgz#4cf7849ae3b47125a567dfee18bfca4254b88c5c"
+  integrity sha512-VfH/XCP0QbQk5B5puLqTLEeFgR8lfCJHZJKkInZ9mkYd+u8byX0kztXEQxEk4wZXJs8HI+7km2ALXjn4YKcX9w==
+  dependencies:
+    "@types/body-parser" "*"
+    "@types/express-serve-static-core" "*"
+    "@types/serve-static" "*"
+
 "@types/fs-extra@^8.0.0":
   version "8.0.0"
   resolved "https://registry.yarnpkg.com/@types/fs-extra/-/fs-extra-8.0.0.tgz#d3e2c313ca29f95059f198dd60d1f774642d4b25"
@@ -2113,7 +2159,7 @@
   resolved "https://registry.yarnpkg.com/@types/lodash/-/lodash-4.14.123.tgz#39be5d211478c8dd3bdae98ee75bb7efe4abfe4d"
   integrity sha512-pQvPkc4Nltyx7G1Ww45OjVqUsJP4UsZm+GWJpigXgkikZqJgRm4c48g027o6tdgubWHwFRF15iFd+Y4Pmqv6+Q==
 
-"@types/mime@^2.0.1":
+"@types/mime@*", "@types/mime@^2.0.1":
   version "2.0.1"
   resolved "https://registry.yarnpkg.com/@types/mime/-/mime-2.0.1.tgz#dc488842312a7f075149312905b5e3c0b054c79d"
   integrity sha512-FwI9gX75FgVBJ7ywgnq/P7tw+/o1GUbtP0KzbtusLigAOgIgNISRK0ZPl4qertvXSIE8YbsVJueQ90cDt9YYyw==
@@ -2135,6 +2181,13 @@
   dependencies:
     "@types/node" "*"
 
+"@types/morgan@^1.7.37":
+  version "1.7.37"
+  resolved "https://registry.yarnpkg.com/@types/morgan/-/morgan-1.7.37.tgz#ebdd0b0f0276073f85283bf4f03c7c54284874df"
+  integrity sha512-tIdEA10BcHcOumMmUiiYdw8lhiVVq62r0ghih5Xpp4WETkfsMiTUZL4w9jCI502BBOrKhFrAOGml9IeELvVaBA==
+  dependencies:
+    "@types/express" "*"
+
 "@types/node-fetch@^2.3.3":
   version "2.3.3"
   resolved "https://registry.yarnpkg.com/@types/node-fetch/-/node-fetch-2.3.3.tgz#eb9c2a0ce8e9424ebe0c0cbe6f1e8ea7576c1310"
@@ -2174,11 +2227,24 @@
     "@types/node" "*"
     xmlbuilder ">=11.0.1"
 
+"@types/range-parser@*":
+  version "1.2.3"
+  resolved "https://registry.yarnpkg.com/@types/range-parser/-/range-parser-1.2.3.tgz#7ee330ba7caafb98090bece86a5ee44115904c2c"
+  integrity sha512-ewFXqrQHlFsgc09MK5jP5iR7vumV/BYayNC6PgJO2LPe8vrnNFyjQjSppfEngITi0qvfKtzFvgKymGheFM9UOA==
+
 "@types/semver@^6.0.2":
   version "6.0.2"
   resolved "https://registry.yarnpkg.com/@types/semver/-/semver-6.0.2.tgz#5e8b09f0e4af53034b1d0fb9977a277847836205"
   integrity sha512-G1Ggy7/9Nsa1Jt2yiBR2riEuyK2DFNnqow6R7cromXPMNynackRY1vqFTLz/gwnef1LHokbXThcPhqMRjUbkpQ==
 
+"@types/serve-static@*":
+  version "1.13.3"
+  resolved "https://registry.yarnpkg.com/@types/serve-static/-/serve-static-1.13.3.tgz#eb7e1c41c4468272557e897e9171ded5e2ded9d1"
+  integrity sha512-oprSwp094zOglVrXdlo/4bAHtKTAxX6VT8FOZlBKrmyLbNvE1zxZyJ6yikMVtHIvwP45+ZQGJn+FdXGKTozq0g==
+  dependencies:
+    "@types/express-serve-static-core" "*"
+    "@types/mime" "*"
+
 "@types/stack-utils@^1.0.1":
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/@types/stack-utils/-/stack-utils-1.0.1.tgz#0a851d3bd96498fa25c33ab7278ed3bd65f06c3e"