diff --git a/.eslintrc.js b/.eslintrc.js
index 37b0d9dd09b9..e0b85157b57e 100644
--- a/.eslintrc.js
+++ b/.eslintrc.js
@@ -132,9 +132,6 @@ module.exports = {
     'flowtype/boolean-style': 2,
     'flowtype/no-primitive-constructor-types': 2,
     'flowtype/require-valid-file-annotation': 2,
-    // These has to be disabled until the whole code base is converted to ESM
-    'import/default': 0,
-    'import/named': 0,
     'import/no-duplicates': 2,
     'import/no-extraneous-dependencies': [
       2,
@@ -149,7 +146,6 @@ module.exports = {
         ],
       },
     ],
-    'import/no-unresolved': [2, {ignore: ['^types/']}],
     // This has to be disabled until all type and module imports are combined
     // https://github.com/benmosher/eslint-plugin-import/issues/645
     'import/order': 0,
diff --git a/integration_tests/__tests__/find_related_files.test.js b/integration_tests/__tests__/find_related_files.test.js
index 431455803498..52755e75658f 100644
--- a/integration_tests/__tests__/find_related_files.test.js
+++ b/integration_tests/__tests__/find_related_files.test.js
@@ -11,10 +11,11 @@
 'use strict';
 
 import runJest from '../runJest';
-import {cleanup, writeFiles} from '../utils';
 import os from 'os';
 import path from 'path';
 
+const {cleanup, writeFiles} = require('../utils');
+
 const skipOnWindows = require('../../scripts/skip_on_windows');
 const DIR = path.resolve(os.tmpdir(), 'find_related_tests_test');
 
diff --git a/integration_tests/__tests__/force_exit.test.js b/integration_tests/__tests__/force_exit.test.js
index 24b6d33868bb..e04c6469ab2d 100644
--- a/integration_tests/__tests__/force_exit.test.js
+++ b/integration_tests/__tests__/force_exit.test.js
@@ -11,9 +11,9 @@
 'use strict';
 
 import runJest from '../runJest';
-import {cleanup, writeFiles} from '../utils';
 import os from 'os';
 import path from 'path';
+const {cleanup, writeFiles} = require('../utils');
 
 const skipOnWindows = require('../../scripts/skip_on_windows');
 const DIR = path.resolve(os.tmpdir(), 'force_exit_test');
diff --git a/integration_tests/__tests__/jest_changed_files.test.js b/integration_tests/__tests__/jest_changed_files.test.js
index 3138ed9c8c79..e2a1fbc3ba9b 100644
--- a/integration_tests/__tests__/jest_changed_files.test.js
+++ b/integration_tests/__tests__/jest_changed_files.test.js
@@ -10,15 +10,15 @@
 
 'use strict';
 
-import {cleanup, run, writeFiles} from '../utils';
 import os from 'os';
 import path from 'path';
 import {
   findRepos,
   getChangedFilesForRoots,
 } from '../../packages/jest-changed-files/src';
-
 const skipOnWindows = require('../../scripts/skip_on_windows');
+const {cleanup, run, writeFiles} = require('../utils');
+
 skipOnWindows.suite();
 
 const DIR = path.resolve(os.tmpdir(), 'jest_changed_files_test_dir');
diff --git a/integration_tests/__tests__/multi_project_runner.test.js b/integration_tests/__tests__/multi_project_runner.test.js
index 1ff2fa796c16..c2a3f25a071c 100644
--- a/integration_tests/__tests__/multi_project_runner.test.js
+++ b/integration_tests/__tests__/multi_project_runner.test.js
@@ -11,10 +11,10 @@
 'use strict';
 
 import runJest from '../runJest';
-import {cleanup, extractSummary, writeFiles} from '../utils';
 import os from 'os';
 import path from 'path';
 
+const {cleanup, extractSummary, writeFiles} = require('../utils');
 const skipOnWindows = require('../../scripts/skip_on_windows');
 const DIR = path.resolve(os.tmpdir(), 'multi_project_runner_test');
 
diff --git a/integration_tests/__tests__/only_changed.test.js b/integration_tests/__tests__/only_changed.test.js
index e1d591f3ba37..e214a9acfcea 100644
--- a/integration_tests/__tests__/only_changed.test.js
+++ b/integration_tests/__tests__/only_changed.test.js
@@ -11,9 +11,9 @@
 'use strict';
 
 import runJest from '../runJest';
-import {cleanup, run, writeFiles} from '../utils';
 import os from 'os';
 import path from 'path';
+const {cleanup, run, writeFiles} = require('../utils');
 
 const skipOnWindows = require('../../scripts/skip_on_windows');
 const DIR = path.resolve(os.tmpdir(), 'jest_only_changed');
diff --git a/integration_tests/__tests__/run_tests_by_path.test.js b/integration_tests/__tests__/run_tests_by_path.test.js
index c54e21e1183a..0dfb2f920da5 100644
--- a/integration_tests/__tests__/run_tests_by_path.test.js
+++ b/integration_tests/__tests__/run_tests_by_path.test.js
@@ -11,9 +11,9 @@
 'use strict';
 
 import runJest from '../runJest';
-import {cleanup, writeFiles} from '../utils';
 import os from 'os';
 import path from 'path';
+const {cleanup, writeFiles} = require('../utils');
 
 const skipOnWindows = require('../../scripts/skip_on_windows');
 const DIR = path.resolve(os.tmpdir(), 'run_tests_by_path_test');
diff --git a/integration_tests/__tests__/test_path_pattern_reporter_message.test.js b/integration_tests/__tests__/test_path_pattern_reporter_message.test.js
index c983254f65b7..0b5599950a11 100644
--- a/integration_tests/__tests__/test_path_pattern_reporter_message.test.js
+++ b/integration_tests/__tests__/test_path_pattern_reporter_message.test.js
@@ -10,9 +10,9 @@
 'use strict';
 
 import runJest from '../runJest';
-import {cleanup, writeFiles} from '../utils';
 import os from 'os';
 import path from 'path';
+const {cleanup, writeFiles} = require('../utils');
 
 const skipOnWindows = require('../../scripts/skip_on_windows');
 const DIR = path.resolve(os.tmpdir(), 'jest_path_pattern_reporter_message');
diff --git a/integration_tests/__tests__/use_stderr.test.js b/integration_tests/__tests__/use_stderr.test.js
index 5a0f3110a8de..5bf113d2728e 100644
--- a/integration_tests/__tests__/use_stderr.test.js
+++ b/integration_tests/__tests__/use_stderr.test.js
@@ -11,9 +11,9 @@
 'use strict';
 
 import runJest from '../runJest';
-import {cleanup, writeFiles} from '../utils';
 import os from 'os';
 import path from 'path';
+const {cleanup, writeFiles} = require('../utils');
 
 const skipOnWindows = require('../../scripts/skip_on_windows');
 const DIR = path.resolve(os.tmpdir(), 'use_stderr_test');
diff --git a/packages/eslint-plugin-jest/src/rules/__tests__/no_focused_tests.test.js b/packages/eslint-plugin-jest/src/rules/__tests__/no_focused_tests.test.js
index 342d3ed0c773..3cdee42d1960 100644
--- a/packages/eslint-plugin-jest/src/rules/__tests__/no_focused_tests.test.js
+++ b/packages/eslint-plugin-jest/src/rules/__tests__/no_focused_tests.test.js
@@ -12,8 +12,8 @@
 
 'use strict';
 
-const RuleTester = require('eslint').RuleTester;
-const rules = require('../../').rules;
+import {RuleTester} from 'eslint';
+const {rules} = require('../../');
 
 const ruleTester = new RuleTester();
 const expectedErrorMessage = 'Unexpected focused test.';
diff --git a/packages/eslint-plugin-jest/src/rules/__tests__/no_identical_title.test.js b/packages/eslint-plugin-jest/src/rules/__tests__/no_identical_title.test.js
index d0358171c84b..fe22ef5ec71f 100644
--- a/packages/eslint-plugin-jest/src/rules/__tests__/no_identical_title.test.js
+++ b/packages/eslint-plugin-jest/src/rules/__tests__/no_identical_title.test.js
@@ -12,8 +12,8 @@
 
 'use strict';
 
-const RuleTester = require('eslint').RuleTester;
-const rules = require('../../').rules;
+import {RuleTester} from 'eslint';
+const {rules} = require('../../');
 
 const ruleTester = new RuleTester();
 
diff --git a/packages/eslint-plugin-jest/src/rules/__tests__/no_skipped_tests.test.js b/packages/eslint-plugin-jest/src/rules/__tests__/no_skipped_tests.test.js
index 8cd3c9d0fc94..d3c7479b853a 100644
--- a/packages/eslint-plugin-jest/src/rules/__tests__/no_skipped_tests.test.js
+++ b/packages/eslint-plugin-jest/src/rules/__tests__/no_skipped_tests.test.js
@@ -12,8 +12,8 @@
 
 'use strict';
 
-const RuleTester = require('eslint').RuleTester;
-const rules = require('../../').rules;
+import {RuleTester} from 'eslint';
+const {rules} = require('../../');
 
 const ruleTester = new RuleTester();
 const expectedErrorMessage = 'Unexpected disabled test.';
diff --git a/packages/eslint-plugin-jest/src/rules/__tests__/valid_expect.test.js b/packages/eslint-plugin-jest/src/rules/__tests__/valid_expect.test.js
index 4610129c3d73..e48c50874cd8 100644
--- a/packages/eslint-plugin-jest/src/rules/__tests__/valid_expect.test.js
+++ b/packages/eslint-plugin-jest/src/rules/__tests__/valid_expect.test.js
@@ -12,8 +12,8 @@
 
 'use strict';
 
-const RuleTester = require('eslint').RuleTester;
-const rules = require('../../').rules;
+import {RuleTester} from 'eslint';
+const {rules} = require('../../');
 
 const ruleTester = new RuleTester();
 
diff --git a/packages/eslint-plugin-jest/src/rules/no_disabled_tests.js b/packages/eslint-plugin-jest/src/rules/no_disabled_tests.js
index d684a3bdef24..cdbb0aa9ef16 100644
--- a/packages/eslint-plugin-jest/src/rules/no_disabled_tests.js
+++ b/packages/eslint-plugin-jest/src/rules/no_disabled_tests.js
@@ -28,7 +28,7 @@ const isPropertyNamedSkip = property =>
 const isCallToTestSkipFunction = callee =>
   matchesTestFunction(callee.object) && isPropertyNamedSkip(callee.property);
 
-module.exports = (context: EslintContext) => ({
+export default (context: EslintContext) => ({
   CallExpression(node: CallExpression) {
     const callee = node.callee;
     if (!callee) {
diff --git a/packages/eslint-plugin-jest/src/rules/no_focused_tests.js b/packages/eslint-plugin-jest/src/rules/no_focused_tests.js
index 2b95ee475947..26874a2d69dd 100644
--- a/packages/eslint-plugin-jest/src/rules/no_focused_tests.js
+++ b/packages/eslint-plugin-jest/src/rules/no_focused_tests.js
@@ -28,7 +28,7 @@ const isPropertyNamedOnly = property =>
 const isCallToTestOnlyFunction = callee =>
   matchesTestFunction(callee.object) && isPropertyNamedOnly(callee.property);
 
-module.exports = (context: EslintContext) => ({
+export default (context: EslintContext) => ({
   CallExpression(node: CallExpression) {
     const callee = node.callee;
     if (!callee) {
diff --git a/packages/eslint-plugin-jest/src/rules/no_identical_title.js b/packages/eslint-plugin-jest/src/rules/no_identical_title.js
index 33db9aa8e689..f4a58ceedc86 100644
--- a/packages/eslint-plugin-jest/src/rules/no_identical_title.js
+++ b/packages/eslint-plugin-jest/src/rules/no_identical_title.js
@@ -82,7 +82,7 @@ const handleTestSuiteTitles = (context, titles, node, title) => {
 const isFirstArgLiteral = node =>
   node.arguments && node.arguments[0] && node.arguments[0].type === 'Literal';
 
-module.exports = (context: EslintContext) => {
+export default (context: EslintContext) => {
   const contexts = [newDescribeContext()];
   return {
     CallExpression(node: CallExpression) {
diff --git a/packages/eslint-plugin-jest/src/rules/valid_expect.js b/packages/eslint-plugin-jest/src/rules/valid_expect.js
index dd7bd41dbc7c..f0c221684f20 100644
--- a/packages/eslint-plugin-jest/src/rules/valid_expect.js
+++ b/packages/eslint-plugin-jest/src/rules/valid_expect.js
@@ -17,7 +17,7 @@ import type {EslintContext, CallExpression} from './types';
 
 const expectProperties = ['not', 'resolves', 'rejects'];
 
-module.exports = (context: EslintContext) => {
+export default (context: EslintContext) => {
   return {
     CallExpression(node: CallExpression) {
       const calleeName = node.callee.name;
diff --git a/packages/jest-changed-files/src/git.js b/packages/jest-changed-files/src/git.js
index e3e7f95b9551..5cf98ede3087 100644
--- a/packages/jest-changed-files/src/git.js
+++ b/packages/jest-changed-files/src/git.js
@@ -70,4 +70,4 @@ const adapter: SCMAdapter = {
   },
 };
 
-module.exports = adapter;
+export default adapter;
diff --git a/packages/jest-changed-files/src/hg.js b/packages/jest-changed-files/src/hg.js
index a33275f596c7..7096f41ed533 100644
--- a/packages/jest-changed-files/src/hg.js
+++ b/packages/jest-changed-files/src/hg.js
@@ -70,4 +70,4 @@ const adapter: SCMAdapter = {
   },
 };
 
-module.exports = adapter;
+export default adapter;
diff --git a/packages/jest-changed-files/src/index.js b/packages/jest-changed-files/src/index.js
index 973887636538..e6abef0fd043 100644
--- a/packages/jest-changed-files/src/index.js
+++ b/packages/jest-changed-files/src/index.js
@@ -22,7 +22,7 @@ const mutex = throat(5);
 const findGitRoot = dir => mutex(() => git.getRoot(dir));
 const findHgRoot = dir => mutex(() => hg.getRoot(dir));
 
-const getChangedFilesForRoots = async (
+export const getChangedFilesForRoots = async (
   roots: Array<Path>,
   options: Options,
 ): ChangedFilesPromise => {
@@ -49,7 +49,7 @@ const getChangedFilesForRoots = async (
   return {changedFiles, repos};
 };
 
-const findRepos = async (roots: Array<Path>): Promise<Repos> => {
+export const findRepos = async (roots: Array<Path>): Promise<Repos> => {
   const gitRepos = await Promise.all(
     roots.reduce((promises, root) => promises.concat(findGitRoot(root)), []),
   );
@@ -62,8 +62,3 @@ const findRepos = async (roots: Array<Path>): Promise<Repos> => {
     hg: new Set(hgRepos.filter(Boolean)),
   };
 };
-
-module.exports = {
-  findRepos,
-  getChangedFilesForRoots,
-};
diff --git a/packages/jest-circus/src/event_handler.js b/packages/jest-circus/src/event_handler.js
index 427663c94893..bf7960f0d395 100644
--- a/packages/jest-circus/src/event_handler.js
+++ b/packages/jest-circus/src/event_handler.js
@@ -81,4 +81,4 @@ const handler: EventHandler = (event, state): void => {
   }
 };
 
-module.exports = handler;
+export default handler;
diff --git a/packages/jest-circus/src/format_node_assert_errors.js b/packages/jest-circus/src/format_node_assert_errors.js
index f8ae42c5789b..1ec5090b5a3c 100644
--- a/packages/jest-circus/src/format_node_assert_errors.js
+++ b/packages/jest-circus/src/format_node_assert_errors.js
@@ -39,7 +39,7 @@ const humanReadableOperators = {
   notDeepStrictEqual: 'not to deeply and strictly equal',
 };
 
-module.exports = (event: Event, state: State) => {
+export default (event: Event, state: State) => {
   switch (event.name) {
     case 'test_failure':
     case 'test_success': {
diff --git a/packages/jest-circus/src/legacy_code_todo_rewrite/jest_adapter.js b/packages/jest-circus/src/legacy_code_todo_rewrite/jest_adapter.js
index 3c221503dbb7..1f7d099cc214 100644
--- a/packages/jest-circus/src/legacy_code_todo_rewrite/jest_adapter.js
+++ b/packages/jest-circus/src/legacy_code_todo_rewrite/jest_adapter.js
@@ -95,4 +95,4 @@ const _addSnapshotData = (results: TestResult, snapshotState) => {
   return results;
 };
 
-module.exports = jestAdapter;
+export default jestAdapter;
diff --git a/packages/jest-circus/src/legacy_code_todo_rewrite/jest_adapter_init.js b/packages/jest-circus/src/legacy_code_todo_rewrite/jest_adapter_init.js
index 280faee7a177..7444a779fb95 100644
--- a/packages/jest-circus/src/legacy_code_todo_rewrite/jest_adapter_init.js
+++ b/packages/jest-circus/src/legacy_code_todo_rewrite/jest_adapter_init.js
@@ -18,9 +18,10 @@ import {SnapshotState, addSerializer} from 'jest-snapshot';
 import {addEventHandler, ROOT_DESCRIBE_BLOCK_NAME} from '../state';
 import {getTestID} from '../utils';
 import run from '../run';
+// eslint-disable-next-line import/default
 import globals from '../index';
 
-const initialize = ({
+export const initialize = ({
   config,
   globalConfig,
   localRequire,
@@ -58,7 +59,7 @@ const initialize = ({
   return {globals, snapshotState};
 };
 
-const runAndTransformResultsToJestFormat = async ({
+export const runAndTransformResultsToJestFormat = async ({
   config,
   globalConfig,
   testPath,
@@ -184,8 +185,3 @@ const _addSuppressedErrors = (test: TestEntry) => {
     test.errors = test.errors.concat(suppressedErrors);
   }
 };
-
-module.exports = {
-  initialize,
-  runAndTransformResultsToJestFormat,
-};
diff --git a/packages/jest-circus/src/legacy_code_todo_rewrite/jest_expect.js b/packages/jest-circus/src/legacy_code_todo_rewrite/jest_expect.js
index 7bbbc42a876b..4b423cb3fbf0 100644
--- a/packages/jest-circus/src/legacy_code_todo_rewrite/jest_expect.js
+++ b/packages/jest-circus/src/legacy_code_todo_rewrite/jest_expect.js
@@ -24,7 +24,7 @@ type JasmineMatcher = {
   negativeCompare: () => RawMatcherFn,
 };
 
-module.exports = (config: {expand: boolean}) => {
+export default (config: {expand: boolean}) => {
   global.expect = expect;
   expect.setState({
     expand: config.expand,
diff --git a/packages/jest-circus/src/run.js b/packages/jest-circus/src/run.js
index 9ebd0d07abac..06ee0e930124 100644
--- a/packages/jest-circus/src/run.js
+++ b/packages/jest-circus/src/run.js
@@ -101,4 +101,4 @@ const _callTest = async (
     .catch(error => dispatch({error, name: 'test_failure', test}));
 };
 
-module.exports = run;
+export default run;
diff --git a/packages/jest-circus/src/state.js b/packages/jest-circus/src/state.js
index b18112469f60..1e6dd771599e 100644
--- a/packages/jest-circus/src/state.js
+++ b/packages/jest-circus/src/state.js
@@ -19,7 +19,7 @@ const eventHandlers: Array<EventHandler> = [
   formatNodeAssertErrors,
 ];
 
-const ROOT_DESCRIBE_BLOCK_NAME = 'ROOT_DESCRIBE_BLOCK';
+export const ROOT_DESCRIBE_BLOCK_NAME = 'ROOT_DESCRIBE_BLOCK';
 const STATE_SYM = Symbol('JEST_STATE_SYMBOL');
 
 const ROOT_DESCRIBE_BLOCK = makeDescribe(ROOT_DESCRIBE_BLOCK_NAME);
@@ -33,23 +33,15 @@ const INITIAL_STATE: State = {
 
 global[STATE_SYM] = INITIAL_STATE;
 
-const getState = (): State => global[STATE_SYM];
-const setState = (state: State): State => (global[STATE_SYM] = state);
+export const getState = (): State => global[STATE_SYM];
+export const setState = (state: State): State => (global[STATE_SYM] = state);
 
-const dispatch = (event: Event): void => {
+export const dispatch = (event: Event): void => {
   for (const handler of eventHandlers) {
     handler(event, getState());
   }
 };
 
-const addEventHandler = (handler: EventHandler): void => {
+export const addEventHandler = (handler: EventHandler): void => {
   eventHandlers.push(handler);
 };
-
-module.exports = {
-  ROOT_DESCRIBE_BLOCK_NAME,
-  addEventHandler,
-  dispatch,
-  getState,
-  setState,
-};
diff --git a/packages/jest-circus/src/utils.js b/packages/jest-circus/src/utils.js
index 20bb4af38d35..5abdc0685f1c 100644
--- a/packages/jest-circus/src/utils.js
+++ b/packages/jest-circus/src/utils.js
@@ -23,7 +23,7 @@ import type {
   TestResults,
 } from 'types/Circus';
 
-const makeDescribe = (
+export const makeDescribe = (
   name: BlockName,
   parent: ?DescribeBlock,
   mode?: BlockMode,
@@ -43,7 +43,7 @@ const makeDescribe = (
   };
 };
 
-const makeTest = (
+export const makeTest = (
   fn: ?TestFn,
   mode: TestMode,
   name: TestName,
@@ -68,7 +68,7 @@ const makeTest = (
   };
 };
 
-const getAllHooksForDescribe = (
+export const getAllHooksForDescribe = (
   describe: DescribeBlock,
 ): {[key: 'beforeAll' | 'afterAll']: Array<Hook>} => {
   const result = {afterAll: [], beforeAll: []};
@@ -87,7 +87,7 @@ const getAllHooksForDescribe = (
   return result;
 };
 
-const getEachHooksForTest = (
+export const getEachHooksForTest = (
   test: TestEntry,
 ): {[key: 'beforeEach' | 'afterEach']: Array<Hook>} => {
   const result = {afterEach: [], beforeEach: []};
@@ -121,7 +121,7 @@ const _makeTimeoutMessage = (timeout, isHook) =>
 // the original values in the variables before we require any files.
 const {setTimeout, clearTimeout} = global;
 
-const callAsyncFn = (
+export const callAsyncFn = (
   fn: AsyncFn,
   testContext: ?TestContext,
   {
@@ -192,12 +192,12 @@ const callAsyncFn = (
     });
 };
 
-const getTestDuration = (test: TestEntry): ?number => {
+export const getTestDuration = (test: TestEntry): ?number => {
   const {startedAt} = test;
   return startedAt ? Date.now() - startedAt : null;
 };
 
-const makeTestResults = (describeBlock: DescribeBlock): TestResults => {
+export const makeTestResults = (describeBlock: DescribeBlock): TestResults => {
   let testResults = [];
   for (const test of describeBlock.tests) {
     const testPath = [];
@@ -228,7 +228,7 @@ const makeTestResults = (describeBlock: DescribeBlock): TestResults => {
 
 // Return a string that identifies the test (concat of parent describe block
 // names + test title)
-const getTestID = (test: TestEntry) => {
+export const getTestID = (test: TestEntry) => {
   const titles = [];
   let parent = test;
   do {
@@ -250,14 +250,3 @@ const _formatError = (error: ?Exception): string => {
     return `${String(error)} thrown`;
   }
 };
-
-module.exports = {
-  callAsyncFn,
-  getAllHooksForDescribe,
-  getEachHooksForTest,
-  getTestDuration,
-  getTestID,
-  makeDescribe,
-  makeTest,
-  makeTestResults,
-};
diff --git a/packages/jest-cli/src/__tests__/generate_empty_coverage.test.js b/packages/jest-cli/src/__tests__/generate_empty_coverage.test.js
index 3ad3ade8536f..cb4eefa921d3 100644
--- a/packages/jest-cli/src/__tests__/generate_empty_coverage.test.js
+++ b/packages/jest-cli/src/__tests__/generate_empty_coverage.test.js
@@ -9,9 +9,9 @@
  */
 'use strict';
 
-const os = require('os');
+import generateEmptyCoverage from '../generate_empty_coverage';
 
-const generateEmptyCoverage = require('../generate_empty_coverage');
+const os = require('os');
 const {makeGlobalConfig, makeProjectConfig} = require('../../../../test_utils');
 
 jest.mock('jest-runtime', () => {
diff --git a/packages/jest-cli/src/__tests__/search_source.test.js b/packages/jest-cli/src/__tests__/search_source.test.js
index 816ebb56f271..df315ccd22a0 100644
--- a/packages/jest-cli/src/__tests__/search_source.test.js
+++ b/packages/jest-cli/src/__tests__/search_source.test.js
@@ -9,9 +9,10 @@
 
 'use strict';
 
+import path from 'path';
+
 jest.setTimeout(15000);
 
-const path = require('path');
 const skipOnWindows = require('../../../../scripts/skip_on_windows');
 
 const rootDir = path.resolve(__dirname, 'test_root');
@@ -34,7 +35,7 @@ describe('SearchSource', () => {
 
   beforeEach(() => {
     Runtime = require('jest-runtime');
-    SearchSource = require('../search_source');
+    SearchSource = require('../search_source').default;
     normalize = require('jest-config').normalize;
   });
 
diff --git a/packages/jest-cli/src/__tests__/test_scheduler.test.js b/packages/jest-cli/src/__tests__/test_scheduler.test.js
index df3c3c95a866..ca66a7aeacc2 100644
--- a/packages/jest-cli/src/__tests__/test_scheduler.test.js
+++ b/packages/jest-cli/src/__tests__/test_scheduler.test.js
@@ -9,8 +9,8 @@
 
 'use strict';
 
-const TestScheduler = require('../test_scheduler');
-const SummaryReporter = require('../reporters/summary_reporter');
+import TestScheduler from '../test_scheduler';
+import SummaryReporter from '../reporters/summary_reporter';
 
 jest.mock('../reporters/default_reporter');
 
diff --git a/packages/jest-cli/src/__tests__/test_sequencer.test.js b/packages/jest-cli/src/__tests__/test_sequencer.test.js
index 82982eb25d2d..c20336766a12 100644
--- a/packages/jest-cli/src/__tests__/test_sequencer.test.js
+++ b/packages/jest-cli/src/__tests__/test_sequencer.test.js
@@ -7,13 +7,12 @@
  */
 'use strict';
 
+import TestSequencer from '../test_sequencer';
+
 jest.mock('fs');
 
 const fs = require('fs');
 const path = require('path');
-
-const TestSequencer = require('../test_sequencer');
-
 const FAIL = 0;
 const SUCCESS = 1;
 
diff --git a/packages/jest-cli/src/__tests__/watch.test.js b/packages/jest-cli/src/__tests__/watch.test.js
index 124f502c97a0..1ab4d5dbe0ae 100644
--- a/packages/jest-cli/src/__tests__/watch.test.js
+++ b/packages/jest-cli/src/__tests__/watch.test.js
@@ -9,9 +9,9 @@
 
 'use strict';
 
-const chalk = require('chalk');
-const TestWatcher = require('../test_watcher');
-const {KEYS} = require('../constants');
+import chalk from 'chalk';
+import TestWatcher from '../test_watcher';
+import {KEYS} from '../constants';
 
 const runJestMock = jest.fn();
 
@@ -31,7 +31,7 @@ jest.doMock(
     },
 );
 
-const watch = require('../watch');
+const watch = require('../watch').default;
 afterEach(runJestMock.mockReset);
 
 describe('Watch mode flows', () => {
diff --git a/packages/jest-cli/src/__tests__/watch_filename_pattern_mode.test.js b/packages/jest-cli/src/__tests__/watch_filename_pattern_mode.test.js
index fb1d98cf721a..7ba93b7b3406 100644
--- a/packages/jest-cli/src/__tests__/watch_filename_pattern_mode.test.js
+++ b/packages/jest-cli/src/__tests__/watch_filename_pattern_mode.test.js
@@ -9,8 +9,8 @@
 
 'use strict';
 
-const chalk = require('chalk');
-const {KEYS} = require('../constants');
+import chalk from 'chalk';
+import {KEYS} from '../constants';
 
 const runJestMock = jest.fn();
 
@@ -84,7 +84,7 @@ jest.doMock('../lib/terminal_utils', () => ({
   getTerminalWidth: () => terminalWidth,
 }));
 
-const watch = require('../watch');
+const watch = require('../watch').default;
 
 const toHex = char => Number(char.charCodeAt(0)).toString(16);
 
diff --git a/packages/jest-cli/src/__tests__/watch_test_name_pattern_mode.test.js b/packages/jest-cli/src/__tests__/watch_test_name_pattern_mode.test.js
index 55568147317c..ff20702f7711 100644
--- a/packages/jest-cli/src/__tests__/watch_test_name_pattern_mode.test.js
+++ b/packages/jest-cli/src/__tests__/watch_test_name_pattern_mode.test.js
@@ -9,8 +9,8 @@
 
 'use strict';
 
-const chalk = require('chalk');
-const {KEYS} = require('../constants');
+import chalk from 'chalk';
+import {KEYS} from '../constants';
 
 const runJestMock = jest.fn();
 
@@ -98,7 +98,7 @@ jest.doMock('../lib/terminal_utils', () => ({
   getTerminalWidth: () => terminalWidth,
 }));
 
-const watch = require('../watch');
+const watch = require('../watch').default;
 
 const toHex = char => Number(char.charCodeAt(0)).toString(16);
 
diff --git a/packages/jest-cli/src/cli/args.js b/packages/jest-cli/src/cli/args.js
index f10c116f5ebf..ceb426fffc99 100644
--- a/packages/jest-cli/src/cli/args.js
+++ b/packages/jest-cli/src/cli/args.js
@@ -13,7 +13,7 @@ import type {Argv} from 'types/Argv';
 import {isJSONString} from 'jest-config';
 import isCI from 'is-ci';
 
-const check = (argv: Argv) => {
+export const check = (argv: Argv) => {
   if (argv.runInBand && argv.hasOwnProperty('maxWorkers')) {
     throw new Error(
       'Both --runInBand and --maxWorkers were specified, but these two ' +
@@ -51,10 +51,11 @@ const check = (argv: Argv) => {
   return true;
 };
 
-const usage = 'Usage: $0 [--config=<pathToConfigFile>] [TestPathPattern]';
-const docs = 'Documentation: https://facebook.github.io/jest/';
+export const usage =
+  'Usage: $0 [--config=<pathToConfigFile>] [TestPathPattern]';
+export const docs = 'Documentation: https://facebook.github.io/jest/';
 
-const options = {
+export const options = {
   all: {
     default: undefined,
     description:
@@ -557,10 +558,3 @@ const options = {
     type: 'boolean',
   },
 };
-
-module.exports = {
-  check,
-  docs,
-  options,
-  usage,
-};
diff --git a/packages/jest-cli/src/cli/get_jest.js b/packages/jest-cli/src/cli/get_jest.js
index 9f47395d59fe..76840ad73d3c 100644
--- a/packages/jest-cli/src/cli/get_jest.js
+++ b/packages/jest-cli/src/cli/get_jest.js
@@ -13,9 +13,10 @@ import type {Path} from 'types/Config';
 import path from 'path';
 import chalk from 'chalk';
 import fs from 'graceful-fs';
+// eslint-disable-next-line import/default
 import jest from '../jest';
 
-function getJest(packageRoot: Path) {
+export default function getJest(packageRoot: Path) {
   const packageJSONPath = path.join(packageRoot, 'package.json');
   const binPath = path.join(packageRoot, 'node_modules/jest-cli');
   if (fs.existsSync(binPath)) {
@@ -45,5 +46,3 @@ function getJest(packageRoot: Path) {
     return jest;
   }
 }
-
-module.exports = getJest;
diff --git a/packages/jest-cli/src/cli/index.js b/packages/jest-cli/src/cli/index.js
index 5b0ab6fd1362..8e93f8a77d70 100644
--- a/packages/jest-cli/src/cli/index.js
+++ b/packages/jest-cli/src/cli/index.js
@@ -20,21 +20,21 @@ import {
 } from 'jest-util';
 import {readConfig} from 'jest-config';
 import {version as VERSION} from '../../package.json';
-import args from './args';
+import * as args from './args';
 import chalk from 'chalk';
 import createContext from '../lib/create_context';
 import getChangedFilesPromise from '../get_changed_files_promise';
 import getJest from './get_jest';
 import handleDeprecationWarnings from '../lib/handle_deprecation_warnings';
 import logDebugMessages from '../lib/log_debug_messages';
-import preRunMessage from '../pre_run_message';
+import {print as preRunMessagePrint} from '../pre_run_message';
 import runJest from '../run_jest';
 import Runtime from 'jest-runtime';
 import TestWatcher from '../test_watcher';
 import watch from '../watch';
 import yargs from 'yargs';
 
-async function run(maybeArgv?: Argv, project?: Path) {
+export async function run(maybeArgv?: Argv, project?: Path) {
   const argv: Argv = _buildArgv(maybeArgv, project);
   const projects = _getProjectListFromCLIArgs(argv, project);
   // If we're running a single Jest project, we might want to use another
@@ -45,7 +45,7 @@ async function run(maybeArgv?: Argv, project?: Path) {
   _readResultsAndExit(results, globalConfig);
 }
 
-const runCLI = async (
+export const runCLI = async (
   argv: Argv,
   projects: Array<Path>,
 ): Promise<{results: AggregatedResult, globalConfig: GlobalConfig}> => {
@@ -347,7 +347,7 @@ const _runWithoutWatch = async (
 ) => {
   const startRun = async () => {
     if (!globalConfig.listTests) {
-      preRunMessage.print(outputStream);
+      preRunMessagePrint(outputStream);
     }
     return await runJest({
       changedFilesPromise,
@@ -361,8 +361,3 @@ const _runWithoutWatch = async (
   };
   return await startRun();
 };
-
-module.exports = {
-  run,
-  runCLI,
-};
diff --git a/packages/jest-cli/src/constants.js b/packages/jest-cli/src/constants.js
index 36088a43b505..0048dd1040e2 100644
--- a/packages/jest-cli/src/constants.js
+++ b/packages/jest-cli/src/constants.js
@@ -10,9 +10,9 @@
 
 const isWindows = process.platform === 'win32';
 
-const CLEAR = isWindows ? '\x1Bc' : '\x1B[2J\x1B[3J\x1B[H';
+export const CLEAR = isWindows ? '\x1Bc' : '\x1B[2J\x1B[3J\x1B[H';
 
-const KEYS = {
+export const KEYS = {
   A: '61',
   ARROW_DOWN: '1b5b42',
   ARROW_LEFT: '1b5b44',
@@ -33,10 +33,8 @@ const KEYS = {
   W: '77',
 };
 
-const ICONS = {
+export const ICONS = {
   failed: isWindows ? '\u00D7' : '\u2715',
   pending: '\u25CB',
   success: isWindows ? '\u221A' : '\u2713',
 };
-
-module.exports = {CLEAR, ICONS, KEYS};
diff --git a/packages/jest-cli/src/generate_empty_coverage.js b/packages/jest-cli/src/generate_empty_coverage.js
index ed4291206b8c..a0edd8886543 100644
--- a/packages/jest-cli/src/generate_empty_coverage.js
+++ b/packages/jest-cli/src/generate_empty_coverage.js
@@ -13,7 +13,7 @@ import type {GlobalConfig, ProjectConfig, Path} from 'types/Config';
 import {createInstrumenter} from 'istanbul-lib-instrument';
 import Runtime from 'jest-runtime';
 
-module.exports = function(
+export default function(
   source: string,
   filename: Path,
   globalConfig: GlobalConfig,
@@ -40,4 +40,4 @@ module.exports = function(
   } else {
     return null;
   }
-};
+}
diff --git a/packages/jest-cli/src/get_changed_files_promise.js b/packages/jest-cli/src/get_changed_files_promise.js
index 0ab3b0b740d2..9db171b1cefc 100644
--- a/packages/jest-cli/src/get_changed_files_promise.js
+++ b/packages/jest-cli/src/get_changed_files_promise.js
@@ -12,7 +12,7 @@ import type {GlobalConfig, ProjectConfig} from 'types/Config';
 import type {ChangedFilesPromise} from 'types/ChangedFiles';
 import {getChangedFilesForRoots} from 'jest-changed-files';
 
-module.exports = (
+export default (
   globalConfig: GlobalConfig,
   configs: Array<ProjectConfig>,
 ): ?ChangedFilesPromise => {
diff --git a/packages/jest-cli/src/get_no_test_found.js b/packages/jest-cli/src/get_no_test_found.js
index 5447068bbc03..dbe3ef19f256 100644
--- a/packages/jest-cli/src/get_no_test_found.js
+++ b/packages/jest-cli/src/get_no_test_found.js
@@ -1,7 +1,7 @@
 import chalk from 'chalk';
 import pluralize from './pluralize';
 
-const getNoTestFound = (testRunData, globalConfig): string => {
+export default function getNoTestFound(testRunData, globalConfig): string {
   const testFiles = testRunData.reduce(
     (current, testRun) => (current += testRun.matches.total),
     0,
@@ -31,6 +31,4 @@ const getNoTestFound = (testRunData, globalConfig): string => {
     '\n' +
     dataMessage
   );
-};
-
-module.exports = getNoTestFound;
+}
diff --git a/packages/jest-cli/src/get_no_test_found_message.js b/packages/jest-cli/src/get_no_test_found_message.js
index ccb3e18f8684..d870c144c47d 100644
--- a/packages/jest-cli/src/get_no_test_found_message.js
+++ b/packages/jest-cli/src/get_no_test_found_message.js
@@ -2,13 +2,14 @@ import getNoTestFound from './get_no_test_found';
 import getNoTestFoundRelatedToChangedFiles from './get_no_test_found_related_to_changed_files';
 import getNoTestFoundVerbose from './get_no_test_found_verbose';
 
-const getNoTestsFoundMessage = (testRunData, globalConfig): string => {
+export default function getNoTestsFoundMessage(
+  testRunData,
+  globalConfig,
+): string {
   if (globalConfig.onlyChanged) {
     return getNoTestFoundRelatedToChangedFiles(globalConfig);
   }
   return testRunData.length === 1 || globalConfig.verbose
     ? getNoTestFoundVerbose(testRunData, globalConfig)
     : getNoTestFound(testRunData, globalConfig);
-};
-
-module.exports = getNoTestsFoundMessage;
+}
diff --git a/packages/jest-cli/src/get_no_test_found_related_to_changed_files.js b/packages/jest-cli/src/get_no_test_found_related_to_changed_files.js
index d6b3971c6a48..89a1e55f82cb 100644
--- a/packages/jest-cli/src/get_no_test_found_related_to_changed_files.js
+++ b/packages/jest-cli/src/get_no_test_found_related_to_changed_files.js
@@ -1,6 +1,6 @@
 import chalk from 'chalk';
 
-const getNoTestFoundRelatedToChangedFiles = globalConfig => {
+export default function getNoTestFoundRelatedToChangedFiles(globalConfig) {
   return (
     chalk.bold('No tests found related to files changed since last commit.\n') +
     chalk.dim(
@@ -9,6 +9,4 @@ const getNoTestFoundRelatedToChangedFiles = globalConfig => {
         : 'Run Jest without `-o` or with `--all` to run all tests.',
     )
   );
-};
-
-module.exports = getNoTestFoundRelatedToChangedFiles;
+}
diff --git a/packages/jest-cli/src/get_no_test_found_verbose.js b/packages/jest-cli/src/get_no_test_found_verbose.js
index 49d7ed058437..6c31ec55e98b 100644
--- a/packages/jest-cli/src/get_no_test_found_verbose.js
+++ b/packages/jest-cli/src/get_no_test_found_verbose.js
@@ -1,7 +1,10 @@
 import chalk from 'chalk';
 import pluralize from './pluralize';
 
-const getNoTestFoundVerbose = (testRunData, globalConfig): string => {
+export default function getNoTestFoundVerbose(
+  testRunData,
+  globalConfig,
+): string {
   const individualResults = testRunData.map(testRun => {
     const stats = testRun.matches.stats || {};
     const config = testRun.context.config;
@@ -49,6 +52,4 @@ const getNoTestFoundVerbose = (testRunData, globalConfig): string => {
     '\n' +
     dataMessage
   );
-};
-
-module.exports = getNoTestFoundVerbose;
+}
diff --git a/packages/jest-cli/src/lib/Prompt.js b/packages/jest-cli/src/lib/Prompt.js
index b2c0cbfda8f5..f5d865d77da7 100644
--- a/packages/jest-cli/src/lib/Prompt.js
+++ b/packages/jest-cli/src/lib/Prompt.js
@@ -12,7 +12,7 @@ import type {ScrollOptions} from './scroll_list';
 
 import {KEYS} from '../constants';
 
-class Prompt {
+export default class Prompt {
   _entering: boolean;
   _value: string;
   _onChange: Function;
@@ -111,5 +111,3 @@ class Prompt {
     return this._entering;
   }
 }
-
-module.exports = Prompt;
diff --git a/packages/jest-cli/src/lib/__tests__/format_test_name_by_pattern.test.js b/packages/jest-cli/src/lib/__tests__/format_test_name_by_pattern.test.js
index 19a7fe1928d5..a241d7c9a586 100644
--- a/packages/jest-cli/src/lib/__tests__/format_test_name_by_pattern.test.js
+++ b/packages/jest-cli/src/lib/__tests__/format_test_name_by_pattern.test.js
@@ -10,7 +10,7 @@
 
 'use strict';
 
-const formatTestNameByPattern = require('../format_test_name_by_pattern');
+import formatTestNameByPattern from '../format_test_name_by_pattern';
 
 describe('for multiline test name returns', () => {
   const testNames = [
diff --git a/packages/jest-cli/src/lib/__tests__/highlight.test.js b/packages/jest-cli/src/lib/__tests__/highlight.test.js
index ab920119352c..5960e54bcf8b 100644
--- a/packages/jest-cli/src/lib/__tests__/highlight.test.js
+++ b/packages/jest-cli/src/lib/__tests__/highlight.test.js
@@ -10,7 +10,7 @@
 
 'use strict';
 
-const highlight = require('../highlight');
+import highlight from '../highlight';
 
 const rootDir = '/Users/foo/dev/jest';
 const rawPath = rootDir + '/jest-cli/__tests__/watch.test.js';
diff --git a/packages/jest-cli/src/lib/__tests__/is_valid_path.test.js b/packages/jest-cli/src/lib/__tests__/is_valid_path.test.js
index c9c6130cfdd9..df3653b3cd41 100644
--- a/packages/jest-cli/src/lib/__tests__/is_valid_path.test.js
+++ b/packages/jest-cli/src/lib/__tests__/is_valid_path.test.js
@@ -8,8 +8,9 @@
 * @flow
 */
 
+import isValidPath from '../is_valid_path';
+
 const path = require('path');
-const isValidPath = require('../is_valid_path');
 const {
   makeGlobalConfig,
   makeProjectConfig,
diff --git a/packages/jest-cli/src/lib/__tests__/log_debug_messages.test.js b/packages/jest-cli/src/lib/__tests__/log_debug_messages.test.js
index 1a3fad919ef5..7e322e08a2a4 100644
--- a/packages/jest-cli/src/lib/__tests__/log_debug_messages.test.js
+++ b/packages/jest-cli/src/lib/__tests__/log_debug_messages.test.js
@@ -8,7 +8,7 @@
 
 'use strict';
 
-const logDebugMessages = require('../log_debug_messages');
+import logDebugMessages from '../log_debug_messages';
 
 jest.mock('../../../package.json', () => ({version: 123}));
 
diff --git a/packages/jest-cli/src/lib/__tests__/prompt.test.js b/packages/jest-cli/src/lib/__tests__/prompt.test.js
index 9598621b8270..938471c070b9 100644
--- a/packages/jest-cli/src/lib/__tests__/prompt.test.js
+++ b/packages/jest-cli/src/lib/__tests__/prompt.test.js
@@ -9,10 +9,10 @@
 */
 'use strict';
 
-const Prompt = require('../Prompt');
-let {KEYS} = require('../../constants');
+import Prompt from '../Prompt';
+import {KEYS} from '../../constants';
 
-KEYS = Object.assign({}, KEYS, {
+const EXTRA_KEYS = Object.assign({}, KEYS, {
   E: '65',
   S: '73',
 });
@@ -26,16 +26,16 @@ it('calls handler on change value', () => {
 
   expect(onChange).toHaveBeenLastCalledWith('', options);
 
-  prompt.put(KEYS.T);
+  prompt.put(EXTRA_KEYS.T);
   expect(onChange).toHaveBeenLastCalledWith('t', options);
 
-  prompt.put(KEYS.E);
+  prompt.put(EXTRA_KEYS.E);
   expect(onChange).toHaveBeenLastCalledWith('te', options);
 
-  prompt.put(KEYS.S);
+  prompt.put(EXTRA_KEYS.S);
   expect(onChange).toHaveBeenLastCalledWith('tes', options);
 
-  prompt.put(KEYS.T);
+  prompt.put(EXTRA_KEYS.T);
   expect(onChange).toHaveBeenLastCalledWith('test', options);
 
   expect(onChange).toHaveBeenCalledTimes(5);
@@ -47,11 +47,11 @@ it('calls handler on success prompt', () => {
 
   prompt.enter(jest.fn(), onSuccess, jest.fn());
 
-  prompt.put(KEYS.T);
-  prompt.put(KEYS.E);
-  prompt.put(KEYS.S);
-  prompt.put(KEYS.T);
-  prompt.put(KEYS.ENTER);
+  prompt.put(EXTRA_KEYS.T);
+  prompt.put(EXTRA_KEYS.E);
+  prompt.put(EXTRA_KEYS.S);
+  prompt.put(EXTRA_KEYS.T);
+  prompt.put(EXTRA_KEYS.ENTER);
 
   expect(onSuccess).toHaveBeenCalledWith('test');
 });
@@ -62,11 +62,11 @@ it('calls handler on cancel prompt', () => {
 
   prompt.enter(jest.fn(), jest.fn(), onCancel);
 
-  prompt.put(KEYS.T);
-  prompt.put(KEYS.E);
-  prompt.put(KEYS.S);
-  prompt.put(KEYS.T);
-  prompt.put(KEYS.ESCAPE);
+  prompt.put(EXTRA_KEYS.T);
+  prompt.put(EXTRA_KEYS.E);
+  prompt.put(EXTRA_KEYS.S);
+  prompt.put(EXTRA_KEYS.T);
+  prompt.put(EXTRA_KEYS.ESCAPE);
 
   expect(onCancel).toHaveBeenCalled();
 });
diff --git a/packages/jest-cli/src/lib/__tests__/scroll_list.test.js b/packages/jest-cli/src/lib/__tests__/scroll_list.test.js
index dfb723e2fb14..a29c327c52e1 100644
--- a/packages/jest-cli/src/lib/__tests__/scroll_list.test.js
+++ b/packages/jest-cli/src/lib/__tests__/scroll_list.test.js
@@ -1,4 +1,4 @@
-const scroll = require('../scroll_list');
+import scroll from '../scroll_list';
 
 it('When offset is -1', () => {
   expect(scroll(25, {max: 10, offset: -1})).toEqual({
diff --git a/packages/jest-cli/src/lib/colorize.js b/packages/jest-cli/src/lib/colorize.js
index c5afc67aca10..b8f83837f409 100644
--- a/packages/jest-cli/src/lib/colorize.js
+++ b/packages/jest-cli/src/lib/colorize.js
@@ -10,7 +10,7 @@
 
 import chalk from 'chalk';
 
-module.exports = (str: string, start: number, end: number) =>
+export default (str: string, start: number, end: number) =>
   chalk.dim(str.slice(0, start)) +
   chalk.reset(str.slice(start, end)) +
   chalk.dim(str.slice(end));
diff --git a/packages/jest-cli/src/lib/create_context.js b/packages/jest-cli/src/lib/create_context.js
index f87414537905..a71e8d0b7eec 100644
--- a/packages/jest-cli/src/lib/create_context.js
+++ b/packages/jest-cli/src/lib/create_context.js
@@ -14,7 +14,7 @@ import type {HasteMap} from 'types/HasteMap';
 
 import Runtime from 'jest-runtime';
 
-module.exports = (
+export default (
   config: ProjectConfig,
   {hasteFS, moduleMap}: HasteMap,
 ): Context => ({
diff --git a/packages/jest-cli/src/lib/format_test_name_by_pattern.js b/packages/jest-cli/src/lib/format_test_name_by_pattern.js
index 1d2d8bddf312..8aaed0beac9c 100644
--- a/packages/jest-cli/src/lib/format_test_name_by_pattern.js
+++ b/packages/jest-cli/src/lib/format_test_name_by_pattern.js
@@ -15,7 +15,7 @@ import colorize from './colorize';
 const DOTS = '...';
 const ENTER = '⏎';
 
-module.exports = (testName: string, pattern: string, width: number) => {
+export default (testName: string, pattern: string, width: number) => {
   const inlineTestName = testName.replace(/(\r\n|\n|\r)/gm, ENTER);
 
   let regexp;
diff --git a/packages/jest-cli/src/lib/handle_deprecation_warnings.js b/packages/jest-cli/src/lib/handle_deprecation_warnings.js
index 32dcc01f4ab1..8d8912705683 100644
--- a/packages/jest-cli/src/lib/handle_deprecation_warnings.js
+++ b/packages/jest-cli/src/lib/handle_deprecation_warnings.js
@@ -12,7 +12,7 @@ import chalk from 'chalk';
 
 import {KEYS} from '../constants';
 
-module.exports = (
+export default (
   pipe: stream$Writable | tty$WriteStream,
   stdin: stream$Readable | tty$ReadStream = process.stdin,
 ) => {
diff --git a/packages/jest-cli/src/lib/highlight.js b/packages/jest-cli/src/lib/highlight.js
index da3523a8fb56..b32d02c0d20b 100644
--- a/packages/jest-cli/src/lib/highlight.js
+++ b/packages/jest-cli/src/lib/highlight.js
@@ -17,12 +17,12 @@ import colorize from './colorize';
 const trim = '...';
 const relativePathHead = './';
 
-const highlight = (
+export default function highlight(
   rawPath: string,
   filePath: string,
   pattern: string,
   rootDir: string,
-) => {
+) {
   let regexp;
 
   try {
@@ -56,6 +56,4 @@ const highlight = (
   const start = match.index - offset;
   const end = start + match[0].length;
   return colorize(filePath, Math.max(start, 0), Math.max(end, trimLength));
-};
-
-module.exports = highlight;
+}
diff --git a/packages/jest-cli/src/lib/is_valid_path.js b/packages/jest-cli/src/lib/is_valid_path.js
index 54ce5f21a548..f5608b091217 100644
--- a/packages/jest-cli/src/lib/is_valid_path.js
+++ b/packages/jest-cli/src/lib/is_valid_path.js
@@ -12,7 +12,7 @@ import type {GlobalConfig, ProjectConfig} from 'types/Config';
 
 const SNAPSHOT_EXTENSION = 'snap';
 
-function isValidPath(
+export default function isValidPath(
   globalConfig: GlobalConfig,
   config: ProjectConfig,
   filePath: string,
@@ -23,5 +23,3 @@ function isValidPath(
     !filePath.endsWith(`.${SNAPSHOT_EXTENSION}`)
   );
 }
-
-module.exports = isValidPath;
diff --git a/packages/jest-cli/src/lib/log_debug_messages.js b/packages/jest-cli/src/lib/log_debug_messages.js
index a73adf8e6ac0..4fb70ff381a9 100644
--- a/packages/jest-cli/src/lib/log_debug_messages.js
+++ b/packages/jest-cli/src/lib/log_debug_messages.js
@@ -12,17 +12,15 @@ import type {GlobalConfig, ProjectConfig} from 'types/Config';
 
 import {version as VERSION} from '../../package.json';
 
-const logDebugMessages = (
+export default function logDebugMessages(
   globalConfig: GlobalConfig,
   configs: Array<ProjectConfig>,
   outputStream: stream$Writable | tty$WriteStream,
-): void => {
+): void {
   const output = {
     configs,
     globalConfig,
     version: VERSION,
   };
   outputStream.write(JSON.stringify(output, null, '  ') + '\n');
-};
-
-module.exports = logDebugMessages;
+}
diff --git a/packages/jest-cli/src/lib/pattern_mode_helpers.js b/packages/jest-cli/src/lib/pattern_mode_helpers.js
index 6aa3861d6557..eff9084cf1ac 100644
--- a/packages/jest-cli/src/lib/pattern_mode_helpers.js
+++ b/packages/jest-cli/src/lib/pattern_mode_helpers.js
@@ -19,7 +19,7 @@ import Prompt from './Prompt';
 const pluralize = (count: number, text: string) =>
   count === 1 ? text : text + 's';
 
-const printPatternMatches = (
+export const printPatternMatches = (
   count: number,
   entity: string,
   pipe: stream$Writable | tty$WriteStream,
@@ -33,7 +33,7 @@ const printPatternMatches = (
   pipe.write(result + extraText);
 };
 
-const printPatternCaret = (
+export const printPatternCaret = (
   pattern: string,
   pipe: stream$Writable | tty$WriteStream,
 ) => {
@@ -44,7 +44,7 @@ const printPatternCaret = (
   pipe.write(ansiEscapes.cursorSavePosition);
 };
 
-const printRestoredPatternCaret = (
+export const printRestoredPatternCaret = (
   pattern: string,
   currentUsageRows: number,
   pipe: stream$Writable | tty$WriteStream,
@@ -57,7 +57,7 @@ const printRestoredPatternCaret = (
   pipe.write(ansiEscapes.cursorRestorePosition);
 };
 
-const printStartTyping = (
+export const printStartTyping = (
   entity: string,
   pipe: stream$Writable | tty$WriteStream,
 ) => {
@@ -68,7 +68,7 @@ const printStartTyping = (
   );
 };
 
-const printMore = (
+export const printMore = (
   entity: string,
   pipe: stream$Writable | tty$WriteStream,
   more: number,
@@ -78,12 +78,12 @@ const printMore = (
   );
 };
 
-const printTypeaheadItem = (
+export const printTypeaheadItem = (
   item: string,
   pipe: stream$Writable | tty$WriteStream,
 ) => pipe.write(`\n ${chalk.dim('\u203A')} ${item}`);
 
-const formatTypeaheadSelection = (
+export const formatTypeaheadSelection = (
   item: string,
   index: number,
   activeIndex: number,
@@ -95,13 +95,3 @@ const formatTypeaheadSelection = (
   }
   return item;
 };
-
-module.exports = {
-  formatTypeaheadSelection,
-  printMore,
-  printPatternCaret,
-  printPatternMatches,
-  printRestoredPatternCaret,
-  printStartTyping,
-  printTypeaheadItem,
-};
diff --git a/packages/jest-cli/src/lib/scroll_list.js b/packages/jest-cli/src/lib/scroll_list.js
index 7832cd3a0125..4c162eda059c 100644
--- a/packages/jest-cli/src/lib/scroll_list.js
+++ b/packages/jest-cli/src/lib/scroll_list.js
@@ -15,7 +15,7 @@ export type ScrollOptions = {
   max: number,
 };
 
-const scroll = (size: number, {offset, max}: ScrollOptions) => {
+export default function scroll(size: number, {offset, max}: ScrollOptions) {
   let start = 0;
   let index = Math.min(offset, size);
 
@@ -35,6 +35,4 @@ const scroll = (size: number, {offset, max}: ScrollOptions) => {
     index,
     start,
   };
-};
-
-module.exports = scroll;
+}
diff --git a/packages/jest-cli/src/lib/terminal_utils.js b/packages/jest-cli/src/lib/terminal_utils.js
index 37d0bbba001d..e0a0f2aa74f1 100644
--- a/packages/jest-cli/src/lib/terminal_utils.js
+++ b/packages/jest-cli/src/lib/terminal_utils.js
@@ -9,8 +9,4 @@
  */
 
 /* $FlowFixMe */
-const getTerminalWidth = (): nubmer => process.stdout.columns;
-
-module.exports = {
-  getTerminalWidth,
-};
+export const getTerminalWidth = (): nubmer => process.stdout.columns;
diff --git a/packages/jest-cli/src/lib/update_global_config.js b/packages/jest-cli/src/lib/update_global_config.js
index 9af007f0a738..bd65cff0d397 100644
--- a/packages/jest-cli/src/lib/update_global_config.js
+++ b/packages/jest-cli/src/lib/update_global_config.js
@@ -18,10 +18,7 @@ type Options = {
   mode?: 'watch' | 'watchAll',
 };
 
-module.exports = (
-  globalConfig: GlobalConfig,
-  options: Options,
-): GlobalConfig => {
+export default (globalConfig: GlobalConfig, options: Options): GlobalConfig => {
   // $FlowFixMe Object.assign
   const newConfig: GlobalConfig = Object.assign({}, globalConfig);
 
diff --git a/packages/jest-cli/src/pattern_prompt.js b/packages/jest-cli/src/pattern_prompt.js
index 8b4cfc656411..811de5e7ed7b 100644
--- a/packages/jest-cli/src/pattern_prompt.js
+++ b/packages/jest-cli/src/pattern_prompt.js
@@ -25,7 +25,7 @@ const usage = (entity: string) =>
 
 const usageRows = usage('').split('\n').length;
 
-module.exports = class PatternPrompt {
+export default class PatternPrompt {
   _pipe: stream$Writable | tty$WriteStream;
   _prompt: Prompt;
   _entityName: string;
@@ -58,4 +58,4 @@ module.exports = class PatternPrompt {
     this._pipe.write(ansiEscapes.eraseLine);
     this._pipe.write(ansiEscapes.cursorLeft);
   }
-};
+}
diff --git a/packages/jest-cli/src/pluralize.js b/packages/jest-cli/src/pluralize.js
index 4ddce0a9dcd2..fef25d2beaee 100644
--- a/packages/jest-cli/src/pluralize.js
+++ b/packages/jest-cli/src/pluralize.js
@@ -1,4 +1,3 @@
-const pluralize = (word: string, count: number, ending: string) =>
-  `${count} ${word}${count === 1 ? '' : ending}`;
-
-module.exports = pluralize;
+export default function pluralize(word: string, count: number, ending: string) {
+  return `${count} ${word}${count === 1 ? '' : ending}`;
+}
diff --git a/packages/jest-cli/src/pre_run_message.js b/packages/jest-cli/src/pre_run_message.js
index a4155c193b52..1a8535cafd08 100644
--- a/packages/jest-cli/src/pre_run_message.js
+++ b/packages/jest-cli/src/pre_run_message.js
@@ -13,19 +13,14 @@ import {clearLine} from 'jest-util';
 import chalk from 'chalk';
 import isCI from 'is-ci';
 
-const print = (stream: stream$Writable | tty$WriteStream) => {
+export const print = (stream: stream$Writable | tty$WriteStream) => {
   if (process.stdout.isTTY && !isCI) {
     stream.write(chalk.bold.dim('Determining test suites to run...'));
   }
 };
 
-const remove = (stream: stream$Writable | tty$WriteStream) => {
+export const remove = (stream: stream$Writable | tty$WriteStream) => {
   if (stream.isTTY && !isCI) {
     clearLine(stream);
   }
 };
-
-module.exports = {
-  print,
-  remove,
-};
diff --git a/packages/jest-cli/src/reporter_dispatcher.js b/packages/jest-cli/src/reporter_dispatcher.js
index ec72faf40660..bc4ea893541e 100644
--- a/packages/jest-cli/src/reporter_dispatcher.js
+++ b/packages/jest-cli/src/reporter_dispatcher.js
@@ -18,7 +18,7 @@ export type RunOptions = {|
   showStatus: boolean,
 |};
 
-class ReporterDispatcher {
+export default class ReporterDispatcher {
   _disabled: boolean;
   _reporters: Array<Reporter>;
 
@@ -78,5 +78,3 @@ class ReporterDispatcher {
     return this.getErrors().length !== 0;
   }
 }
-
-module.exports = ReporterDispatcher;
diff --git a/packages/jest-cli/src/reporters/Status.js b/packages/jest-cli/src/reporters/Status.js
index 7c2267920893..b2102d125a46 100644
--- a/packages/jest-cli/src/reporters/Status.js
+++ b/packages/jest-cli/src/reporters/Status.js
@@ -63,7 +63,7 @@ class CurrentTestList {
  * and also provides an ANSI escape sequence to remove status lines
  * from the terminal.
  */
-class Status {
+export default class Status {
   _cache: ?{content: string, clear: string};
   _callback: () => void;
   _currentTests: CurrentTestList;
@@ -201,5 +201,3 @@ class Status {
     this._debouncedEmit();
   }
 }
-
-module.exports = Status;
diff --git a/packages/jest-cli/src/reporters/__tests__/coverage_reporter.test.js b/packages/jest-cli/src/reporters/__tests__/coverage_reporter.test.js
index 3c37178a17b0..8a74b93a3b1c 100644
--- a/packages/jest-cli/src/reporters/__tests__/coverage_reporter.test.js
+++ b/packages/jest-cli/src/reporters/__tests__/coverage_reporter.test.js
@@ -27,7 +27,7 @@ beforeEach(() => {
     write: jest.fn(),
   }));
 
-  CoverageReporter = require('../coverage_reporter');
+  CoverageReporter = require('../coverage_reporter').default;
   libCoverage = require('istanbul-lib-coverage');
   libSourceMaps = require('istanbul-lib-source-maps');
 
diff --git a/packages/jest-cli/src/reporters/__tests__/coverage_worker.test.js b/packages/jest-cli/src/reporters/__tests__/coverage_worker.test.js
index 6bc082d4a38c..ada6a847c29a 100644
--- a/packages/jest-cli/src/reporters/__tests__/coverage_worker.test.js
+++ b/packages/jest-cli/src/reporters/__tests__/coverage_worker.test.js
@@ -22,7 +22,7 @@ beforeEach(() => {
   jest.resetModules();
 
   fs = require('fs');
-  generateEmptyCoverage = require('../../generate_empty_coverage');
+  generateEmptyCoverage = require('../../generate_empty_coverage').default;
   worker = require('../coverage_worker');
 });
 
diff --git a/packages/jest-cli/src/reporters/__tests__/default_reporter.test.js b/packages/jest-cli/src/reporters/__tests__/default_reporter.test.js
index dd96671c1a13..ded4eea8aa69 100644
--- a/packages/jest-cli/src/reporters/__tests__/default_reporter.test.js
+++ b/packages/jest-cli/src/reporters/__tests__/default_reporter.test.js
@@ -52,7 +52,7 @@ beforeEach(() => {
   process.stderr.write = jest.fn();
   stdout = process.stdout.write = jest.fn();
 
-  DefaultReporter = require('../default_reporter');
+  DefaultReporter = require('../default_reporter').default;
 });
 
 afterEach(() => {
diff --git a/packages/jest-cli/src/reporters/__tests__/get_snapshot_status.test.js b/packages/jest-cli/src/reporters/__tests__/get_snapshot_status.test.js
index e9ba8053db20..fa11a00a5b0f 100644
--- a/packages/jest-cli/src/reporters/__tests__/get_snapshot_status.test.js
+++ b/packages/jest-cli/src/reporters/__tests__/get_snapshot_status.test.js
@@ -9,7 +9,7 @@
 
 'use strict';
 
-const getSnapshotStatus = require('../get_snapshot_status');
+import getSnapshotStatus from '../get_snapshot_status';
 
 test('Retrieves the snapshot status', () => {
   const snapshotResult = {
diff --git a/packages/jest-cli/src/reporters/__tests__/utils.test.js b/packages/jest-cli/src/reporters/__tests__/utils.test.js
index f6c7987d84c9..5e8909a7db64 100644
--- a/packages/jest-cli/src/reporters/__tests__/utils.test.js
+++ b/packages/jest-cli/src/reporters/__tests__/utils.test.js
@@ -7,10 +7,10 @@
  *
  */
 
-const path = require('path');
-const chalk = require('chalk');
-const stripAnsi = require('strip-ansi');
-const {wrapAnsiString, trimAndFormatPath} = require('../utils');
+import path from 'path';
+import chalk from 'chalk';
+import stripAnsi from 'strip-ansi';
+import {trimAndFormatPath, wrapAnsiString} from '../utils';
 
 describe('wrapAnsiString()', () => {
   it('wraps a long string containing ansi chars', () => {
diff --git a/packages/jest-cli/src/reporters/__tests__/verbose_reporter.test.js b/packages/jest-cli/src/reporters/__tests__/verbose_reporter.test.js
index 27669b73a9f0..44cbd554161c 100644
--- a/packages/jest-cli/src/reporters/__tests__/verbose_reporter.test.js
+++ b/packages/jest-cli/src/reporters/__tests__/verbose_reporter.test.js
@@ -12,7 +12,8 @@ const wrap = obj => ({suites: obj, tests: [], title: ''});
 let groupTestsBySuites;
 
 beforeEach(() => {
-  groupTestsBySuites = require('../verbose_reporter').groupTestsBySuites;
+  const VerboseReporter = require('../verbose_reporter').default;
+  groupTestsBySuites = VerboseReporter.groupTestsBySuites;
 });
 
 describe('groupTestsBySuites', () => {
diff --git a/packages/jest-cli/src/reporters/base_reporter.js b/packages/jest-cli/src/reporters/base_reporter.js
index 9716acb3650e..2fb8d0d46f72 100644
--- a/packages/jest-cli/src/reporters/base_reporter.js
+++ b/packages/jest-cli/src/reporters/base_reporter.js
@@ -13,9 +13,9 @@ import type {Context} from 'types/Context';
 import type {Test} from 'types/TestRunner';
 import type {ReporterOnStartOptions} from 'types/Reporters';
 
-import preRunMessage from '../pre_run_message';
+import {remove as preRunMessageRemove} from '../pre_run_message';
 
-class BaseReporter {
+export default class BaseReporter {
   _error: ?Error;
 
   log(message: string) {
@@ -23,7 +23,7 @@ class BaseReporter {
   }
 
   onRunStart(results: AggregatedResult, options: ReporterOnStartOptions) {
-    preRunMessage.remove(process.stderr);
+    preRunMessageRemove(process.stderr);
   }
 
   onTestResult(test: Test, testResult: TestResult, results: AggregatedResult) {}
@@ -45,5 +45,3 @@ class BaseReporter {
     return this._error;
   }
 }
-
-module.exports = BaseReporter;
diff --git a/packages/jest-cli/src/reporters/coverage_reporter.js b/packages/jest-cli/src/reporters/coverage_reporter.js
index e894fe0b2703..ec2fa83a1e83 100644
--- a/packages/jest-cli/src/reporters/coverage_reporter.js
+++ b/packages/jest-cli/src/reporters/coverage_reporter.js
@@ -29,6 +29,7 @@ import libSourceMaps from 'istanbul-lib-source-maps';
 import pify from 'pify';
 import workerFarm from 'worker-farm';
 import BaseReporter from './base_reporter';
+// eslint-disable-next-line import/default
 import CoverageWorker from './coverage_worker';
 import path from 'path';
 import glob from 'glob';
@@ -38,7 +39,7 @@ const RUNNING_TEST_COLOR = chalk.bold.dim;
 
 const isInteractive = process.stdout.isTTY && !isCI;
 
-class CoverageReporter extends BaseReporter {
+export default class CoverageReporter extends BaseReporter {
   _coverageMap: CoverageMap;
   _globalConfig: GlobalConfig;
   _sourceMapStore: any;
@@ -313,5 +314,3 @@ class CoverageReporter extends BaseReporter {
     return this._coverageMap;
   }
 }
-
-module.exports = CoverageReporter;
diff --git a/packages/jest-cli/src/reporters/coverage_worker.js b/packages/jest-cli/src/reporters/coverage_worker.js
index 25ef877458ba..6634bf86547d 100644
--- a/packages/jest-cli/src/reporters/coverage_worker.js
+++ b/packages/jest-cli/src/reporters/coverage_worker.js
@@ -43,6 +43,7 @@ process.on('uncaughtException', err => {
   process.exit(1);
 });
 
+// Cannot use ESM export as worker-farm chokes
 module.exports = (
   {config, globalConfig, path}: CoverageWorkerData,
   callback: WorkerCallback,
diff --git a/packages/jest-cli/src/reporters/default_reporter.js b/packages/jest-cli/src/reporters/default_reporter.js
index 64093c91652c..765297216125 100644
--- a/packages/jest-cli/src/reporters/default_reporter.js
+++ b/packages/jest-cli/src/reporters/default_reporter.js
@@ -30,7 +30,7 @@ const TITLE_BULLET = chalk.bold('\u25cf ');
 
 const isInteractive = process.stdin.isTTY && !isCI;
 
-class DefaultReporter extends BaseReporter {
+export default class DefaultReporter extends BaseReporter {
   _clear: string; // ANSI clear sequence for the last printed status
   _err: write;
   _globalConfig: GlobalConfig;
@@ -200,5 +200,3 @@ class DefaultReporter extends BaseReporter {
     }
   }
 }
-
-module.exports = DefaultReporter;
diff --git a/packages/jest-cli/src/reporters/get_result_header.js b/packages/jest-cli/src/reporters/get_result_header.js
index f1fedc71880a..076bd2891396 100644
--- a/packages/jest-cli/src/reporters/get_result_header.js
+++ b/packages/jest-cli/src/reporters/get_result_header.js
@@ -28,7 +28,7 @@ const PASS = chalk.supportsColor
   ? chalk.reset.inverse.bold.green(` ${PASS_TEXT} `)
   : PASS_TEXT;
 
-module.exports = (
+export default (
   result: TestResult,
   globalConfig: GlobalConfig,
   projectConfig?: ProjectConfig,
diff --git a/packages/jest-cli/src/reporters/get_snapshot_status.js b/packages/jest-cli/src/reporters/get_snapshot_status.js
index ebd7f34b9f5c..b8557ca87289 100644
--- a/packages/jest-cli/src/reporters/get_snapshot_status.js
+++ b/packages/jest-cli/src/reporters/get_snapshot_status.js
@@ -20,7 +20,7 @@ const SNAPSHOT_ADDED = chalk.bold.green;
 const SNAPSHOT_REMOVED = chalk.bold.red;
 const SNAPSHOT_UPDATED = chalk.bold.green;
 
-module.exports = (
+export default (
   snapshot: $PropertyType<TestResult, 'snapshot'>,
   afterUpdate: boolean,
 ): Array<string> => {
diff --git a/packages/jest-cli/src/reporters/get_snapshot_summary.js b/packages/jest-cli/src/reporters/get_snapshot_summary.js
index a7b5c6b0da06..0b38c6f21a68 100644
--- a/packages/jest-cli/src/reporters/get_snapshot_summary.js
+++ b/packages/jest-cli/src/reporters/get_snapshot_summary.js
@@ -21,7 +21,7 @@ const SNAPSHOT_REMOVED = chalk.bold.red;
 const SNAPSHOT_SUMMARY = chalk.bold;
 const SNAPSHOT_UPDATED = chalk.bold.green;
 
-module.exports = (
+export default (
   snapshots: SnapshotSummary,
   updateCommand: string,
 ): Array<string> => {
diff --git a/packages/jest-cli/src/reporters/notify_reporter.js b/packages/jest-cli/src/reporters/notify_reporter.js
index bc0930258f6c..b4b2a30d9596 100644
--- a/packages/jest-cli/src/reporters/notify_reporter.js
+++ b/packages/jest-cli/src/reporters/notify_reporter.js
@@ -21,7 +21,7 @@ const isDarwin = process.platform === 'darwin';
 
 const icon = path.resolve(__dirname, '../assets/jest_logo.png');
 
-class NotifyReporter extends BaseReporter {
+export default class NotifyReporter extends BaseReporter {
   _startRun: (globalConfig: GlobalConfig) => *;
   _globalConfig: GlobalConfig;
 
@@ -85,5 +85,3 @@ class NotifyReporter extends BaseReporter {
     }
   }
 }
-
-module.exports = NotifyReporter;
diff --git a/packages/jest-cli/src/reporters/summary_reporter.js b/packages/jest-cli/src/reporters/summary_reporter.js
index 9d9b02ce0a51..455790538c3c 100644
--- a/packages/jest-cli/src/reporters/summary_reporter.js
+++ b/packages/jest-cli/src/reporters/summary_reporter.js
@@ -49,7 +49,7 @@ const NPM_EVENTS = new Set([
   'postrestart',
 ]);
 
-class SummaryReporter extends BaseReporter {
+export default class SummaryReporter extends BaseReporter {
   _estimatedTime: number;
   _globalConfig: GlobalConfig;
 
@@ -224,5 +224,3 @@ class SummaryReporter extends BaseReporter {
     );
   }
 }
-
-module.exports = SummaryReporter;
diff --git a/packages/jest-cli/src/reporters/utils.js b/packages/jest-cli/src/reporters/utils.js
index b3d6b729696c..242a4dd5a438 100644
--- a/packages/jest-cli/src/reporters/utils.js
+++ b/packages/jest-cli/src/reporters/utils.js
@@ -23,7 +23,7 @@ type SummaryOptions = {|
 
 const PROGRESS_BAR_WIDTH = 40;
 
-const printDisplayName = (config: ProjectConfig) => {
+export const printDisplayName = (config: ProjectConfig) => {
   const {displayName} = config;
 
   if (displayName) {
@@ -35,7 +35,7 @@ const printDisplayName = (config: ProjectConfig) => {
   return '';
 };
 
-const trimAndFormatPath = (
+export const trimAndFormatPath = (
   pad: number,
   config: ProjectConfig | GlobalConfig,
   testPath: Path,
@@ -72,7 +72,7 @@ const trimAndFormatPath = (
   );
 };
 
-const formatTestPath = (
+export const formatTestPath = (
   config: GlobalConfig | ProjectConfig,
   testPath: Path,
 ) => {
@@ -80,7 +80,10 @@ const formatTestPath = (
   return chalk.dim(dirname + path.sep) + chalk.bold(basename);
 };
 
-const relativePath = (config: GlobalConfig | ProjectConfig, testPath: Path) => {
+export const relativePath = (
+  config: GlobalConfig | ProjectConfig,
+  testPath: Path,
+) => {
   // this function can be called with ProjectConfigs or GlobalConfigs. GlobalConfigs
   // do not have config.cwd, only config.rootDir. Try using config.cwd, fallback
   // to config.rootDir. (Also, some unit just use config.rootDir, which is ok)
@@ -90,10 +93,10 @@ const relativePath = (config: GlobalConfig | ProjectConfig, testPath: Path) => {
   return {basename, dirname};
 };
 
-const pluralize = (word: string, count: number) =>
+export const pluralize = (word: string, count: number) =>
   `${count} ${word}${count === 1 ? '' : 's'}`;
 
-const getSummary = (
+export const getSummary = (
   aggregatedResults: AggregatedResult,
   options?: SummaryOptions,
 ) => {
@@ -188,7 +191,7 @@ const renderTime = (runTime, estimatedTime, width) => {
 
 // word-wrap a string that contains ANSI escape sequences.
 // ANSI escape sequences do not add to the string length.
-const wrapAnsiString = (string: string, terminalWidth: number) => {
+export const wrapAnsiString = (string: string, terminalWidth: number) => {
   if (terminalWidth === 0) {
     // if the terminal width is zero, don't bother word-wrapping
     return string;
@@ -248,13 +251,3 @@ const wrapAnsiString = (string: string, terminalWidth: number) => {
     )
     .join('\n');
 };
-
-module.exports = {
-  formatTestPath,
-  getSummary,
-  pluralize,
-  printDisplayName,
-  relativePath,
-  trimAndFormatPath,
-  wrapAnsiString,
-};
diff --git a/packages/jest-cli/src/reporters/verbose_reporter.js b/packages/jest-cli/src/reporters/verbose_reporter.js
index 9d0012a1908c..9e3c483a20da 100644
--- a/packages/jest-cli/src/reporters/verbose_reporter.js
+++ b/packages/jest-cli/src/reporters/verbose_reporter.js
@@ -21,7 +21,7 @@ import chalk from 'chalk';
 import {ICONS} from '../constants';
 import DefaultReporter from './default_reporter';
 
-class VerboseReporter extends DefaultReporter {
+export default class VerboseReporter extends DefaultReporter {
   _globalConfig: GlobalConfig;
 
   constructor(globalConfig: GlobalConfig) {
@@ -128,5 +128,3 @@ class VerboseReporter extends DefaultReporter {
     this.log(indentation + (str || ''));
   }
 }
-
-module.exports = VerboseReporter;
diff --git a/packages/jest-cli/src/run_jest.js b/packages/jest-cli/src/run_jest.js
index 3afdf315b89f..42351d56a87e 100644
--- a/packages/jest-cli/src/run_jest.js
+++ b/packages/jest-cli/src/run_jest.js
@@ -78,7 +78,7 @@ const processResults = (runResults, options) => {
   return options.onComplete && options.onComplete(runResults);
 };
 
-const runJest = async ({
+export default async function runJest({
   contexts,
   globalConfig,
   outputStream,
@@ -94,7 +94,7 @@ const runJest = async ({
   startRun: (globalConfig: GlobalConfig) => *,
   changedFilesPromise: ?ChangedFilesPromise,
   onComplete: (testResults: AggregatedResult) => any,
-}) => {
+}) {
   const sequencer = new TestSequencer();
   let allTests = [];
   const testRunData = await Promise.all(
@@ -159,6 +159,4 @@ const runJest = async ({
     outputFile: globalConfig.outputFile,
     testResultsProcessor: globalConfig.testResultsProcessor,
   });
-};
-
-module.exports = runJest;
+}
diff --git a/packages/jest-cli/src/search_source.js b/packages/jest-cli/src/search_source.js
index 47d8a29c324f..31050a77cb77 100644
--- a/packages/jest-cli/src/search_source.js
+++ b/packages/jest-cli/src/search_source.js
@@ -63,7 +63,7 @@ const toTests = (context, tests) =>
     path,
   }));
 
-class SearchSource {
+export default class SearchSource {
   _context: Context;
   _rootPattern: RegExp;
   _testIgnorePattern: ?RegExp;
@@ -217,5 +217,3 @@ class SearchSource {
     }
   }
 }
-
-module.exports = SearchSource;
diff --git a/packages/jest-cli/src/test_name_pattern_prompt.js b/packages/jest-cli/src/test_name_pattern_prompt.js
index f5b4117292c8..8a18b4d9228f 100644
--- a/packages/jest-cli/src/test_name_pattern_prompt.js
+++ b/packages/jest-cli/src/test_name_pattern_prompt.js
@@ -27,7 +27,7 @@ import {
 } from './lib/pattern_mode_helpers';
 import PatternPrompt from './pattern_prompt';
 
-module.exports = class TestNamePatternPrompt extends PatternPrompt {
+export default class TestNamePatternPrompt extends PatternPrompt {
   _cachedTestResults: Array<TestResult>;
 
   constructor(pipe: stream$Writable | tty$WriteStream, prompt: Prompt) {
@@ -103,4 +103,4 @@ module.exports = class TestNamePatternPrompt extends PatternPrompt {
   updateCachedTestResults(testResults: Array<TestResult> = []) {
     this._cachedTestResults = testResults;
   }
-};
+}
diff --git a/packages/jest-cli/src/test_path_pattern_prompt.js b/packages/jest-cli/src/test_path_pattern_prompt.js
index a0cda1ec6586..b4915e371e71 100644
--- a/packages/jest-cli/src/test_path_pattern_prompt.js
+++ b/packages/jest-cli/src/test_path_pattern_prompt.js
@@ -11,7 +11,6 @@
 import type {Context} from 'types/Context';
 import type {Test} from 'types/TestRunner';
 import type {ScrollOptions} from './lib/scroll_list';
-// eslint-disable-next-line import/default
 import type SearchSource from './search_source';
 
 import chalk from 'chalk';
@@ -37,7 +36,7 @@ type SearchSources = Array<{|
   searchSource: SearchSource,
 |}>;
 
-module.exports = class TestPathPatternPrompt extends PatternPrompt {
+export default class TestPathPatternPrompt extends PatternPrompt {
   _searchSources: SearchSources;
 
   constructor(pipe: stream$Writable | tty$WriteStream, prompt: Prompt) {
@@ -112,4 +111,4 @@ module.exports = class TestPathPatternPrompt extends PatternPrompt {
   updateSearchSources(searchSources: SearchSources) {
     this._searchSources = searchSources;
   }
-};
+}
diff --git a/packages/jest-cli/src/test_path_pattern_to_regexp.js b/packages/jest-cli/src/test_path_pattern_to_regexp.js
index b4e2372f7493..1ee3634772d2 100644
--- a/packages/jest-cli/src/test_path_pattern_to_regexp.js
+++ b/packages/jest-cli/src/test_path_pattern_to_regexp.js
@@ -11,4 +11,4 @@
 // Because we serialize/deserialize globalConfig when we spawn workers,
 // we can't pass regular expression. Using this shared function on both sides
 // will ensure that we produce consistent regexp for testPathPattern.
-module.exports = (testPathPattern: string) => new RegExp(testPathPattern, 'i');
+export default (testPathPattern: string) => new RegExp(testPathPattern, 'i');
diff --git a/packages/jest-cli/src/test_result_helpers.js b/packages/jest-cli/src/test_result_helpers.js
index 1914747357ee..53528f8453d5 100644
--- a/packages/jest-cli/src/test_result_helpers.js
+++ b/packages/jest-cli/src/test_result_helpers.js
@@ -14,7 +14,7 @@ import type {
   TestResult,
 } from 'types/TestResult';
 
-const makeEmptyAggregatedTestResult = (): AggregatedResult => {
+export const makeEmptyAggregatedTestResult = (): AggregatedResult => {
   return {
     numFailedTestSuites: 0,
     numFailedTests: 0,
@@ -47,7 +47,7 @@ const makeEmptyAggregatedTestResult = (): AggregatedResult => {
   };
 };
 
-const buildFailureTestResult = (
+export const buildFailureTestResult = (
   testPath: string,
   err: SerializableError,
 ): TestResult => {
@@ -79,7 +79,7 @@ const buildFailureTestResult = (
 };
 
 // Add individual test result to an aggregated test result
-const addResult = (
+export const addResult = (
   aggregatedResults: AggregatedResult,
   testResult: TestResult,
 ): void => {
@@ -129,9 +129,3 @@ const addResult = (
     testResult.snapshot.unmatched +
     testResult.snapshot.updated;
 };
-
-module.exports = {
-  addResult,
-  buildFailureTestResult,
-  makeEmptyAggregatedTestResult,
-};
diff --git a/packages/jest-cli/src/test_scheduler.js b/packages/jest-cli/src/test_scheduler.js
index 60e1a6b89674..036eadc919ac 100644
--- a/packages/jest-cli/src/test_scheduler.js
+++ b/packages/jest-cli/src/test_scheduler.js
@@ -39,7 +39,7 @@ export type TestSchedulerOptions = {|
   startRun: (globalConfig: GlobalConfig) => *,
 |};
 
-class TestScheduler {
+export default class TestScheduler {
   _dispatcher: ReporterDispatcher;
   _globalConfig: GlobalConfig;
   _options: TestSchedulerOptions;
@@ -333,5 +333,3 @@ const getEstimatedTime = (timings, workers) => {
     ? max
     : Math.max(timings.reduce((sum, time) => sum + time) / workers, max);
 };
-
-module.exports = TestScheduler;
diff --git a/packages/jest-cli/src/test_sequencer.js b/packages/jest-cli/src/test_sequencer.js
index 3b1ea9d9d0e7..82292c4346e9 100644
--- a/packages/jest-cli/src/test_sequencer.js
+++ b/packages/jest-cli/src/test_sequencer.js
@@ -23,7 +23,7 @@ type Cache = {
   [key: string]: [0 | 1, number],
 };
 
-class TestSequencer {
+export default class TestSequencer {
   _cache: Map<Context, Cache>;
 
   constructor() {
@@ -113,5 +113,3 @@ class TestSequencer {
     );
   }
 }
-
-module.exports = TestSequencer;
diff --git a/packages/jest-cli/src/test_watcher.js b/packages/jest-cli/src/test_watcher.js
index 380e40ed6489..67c779499279 100644
--- a/packages/jest-cli/src/test_watcher.js
+++ b/packages/jest-cli/src/test_watcher.js
@@ -14,7 +14,7 @@ type State = {|
   interrupted: boolean,
 |};
 
-class TestWatcher extends EventEmitter {
+export default class TestWatcher extends EventEmitter {
   state: State;
   _isWatchMode: boolean;
 
@@ -37,5 +37,3 @@ class TestWatcher extends EventEmitter {
     return this._isWatchMode;
   }
 }
-
-module.exports = TestWatcher;
diff --git a/packages/jest-cli/src/watch.js b/packages/jest-cli/src/watch.js
index e1e7785b298d..1af7351050ae 100644
--- a/packages/jest-cli/src/watch.js
+++ b/packages/jest-cli/src/watch.js
@@ -18,7 +18,7 @@ import {replacePathSepForRegex} from 'jest-regex-util';
 import HasteMap from 'jest-haste-map';
 import isCI from 'is-ci';
 import isValidPath from './lib/is_valid_path';
-import preRunMessage from './pre_run_message';
+import {print as preRunMessagePrint} from './pre_run_message';
 import createContext from './lib/create_context';
 import runJest from './run_jest';
 import updateGlobalConfig from './lib/update_global_config';
@@ -32,13 +32,13 @@ import {KEYS, CLEAR} from './constants';
 const isInteractive = process.stdout.isTTY && !isCI;
 let hasExitListener = false;
 
-const watch = (
+export default function watch(
   initialGlobalConfig: GlobalConfig,
   contexts: Array<Context>,
   outputStream: stream$Writable | tty$WriteStream,
   hasteMapInstances: Array<HasteMap>,
   stdin?: stream$Readable | tty$ReadStream = process.stdin,
-) => {
+) {
   // `globalConfig` will be consantly updated and reassigned as a result of
   // watch mode interactions.
   let globalConfig = initialGlobalConfig;
@@ -105,7 +105,7 @@ const watch = (
 
     testWatcher = new TestWatcher({isWatchMode: true});
     isInteractive && outputStream.write(CLEAR);
-    preRunMessage.print(outputStream);
+    preRunMessagePrint(outputStream);
     isRunning = true;
     const configs = contexts.map(context => context.config);
     const changedFilesPromise = getChangedFilesPromise(globalConfig, configs);
@@ -260,7 +260,7 @@ const watch = (
 
   startRun(globalConfig);
   return Promise.resolve();
-};
+}
 
 const activeFilters = (globalConfig: GlobalConfig, delimiter = '\n') => {
   const {testNamePattern, testPathPattern} = globalConfig;
@@ -336,5 +336,3 @@ const showToggleUsagePrompt = () =>
   chalk.dim('Press ') +
   'w' +
   chalk.dim(' to show more.');
-
-module.exports = watch;
diff --git a/packages/jest-config/src/__tests__/get_max_workers.test.js b/packages/jest-config/src/__tests__/get_max_workers.test.js
index 1056566a22af..1636ac13abc7 100644
--- a/packages/jest-config/src/__tests__/get_max_workers.test.js
+++ b/packages/jest-config/src/__tests__/get_max_workers.test.js
@@ -8,7 +8,7 @@
 * @emails oncall+jsinfra
 */
 
-const getMaxWorkers = require('../get_max_workers');
+import getMaxWorkers from '../get_max_workers';
 
 jest.mock('os', () => ({
   cpus: () => ({length: 4}),
diff --git a/packages/jest-config/src/__tests__/normalize.test.js b/packages/jest-config/src/__tests__/normalize.test.js
index 57812320784f..2d7ead49d7bc 100644
--- a/packages/jest-config/src/__tests__/normalize.test.js
+++ b/packages/jest-config/src/__tests__/normalize.test.js
@@ -6,7 +6,9 @@
  * of patent rights can be found in the PATENTS file in the same directory.
  *
  */
-'use strict';
+
+import {escapeStrForRegex} from 'jest-regex-util';
+import normalize from '../normalize';
 
 jest.mock('jest-resolve');
 
@@ -14,9 +16,6 @@ jest.mock('path', () => require.requireActual('path').posix);
 
 const crypto = require('crypto');
 const path = require('path');
-const utils = require('jest-regex-util');
-const normalize = require('../normalize');
-
 const DEFAULT_JS_PATTERN = require('../constants').DEFAULT_JS_PATTERN;
 const DEFAULT_CSS_PATTERN = '^.+\\.(css)$';
 
@@ -37,10 +36,7 @@ const findNodeModule = jest.fn(name => {
 // regular expressions. This little helper function helps us generate the
 // expected strings for checking path patterns.
 function joinForPattern() {
-  return Array.prototype.join.call(
-    arguments,
-    utils.escapeStrForRegex(path.sep),
-  );
+  return Array.prototype.join.call(arguments, escapeStrForRegex(path.sep));
 }
 
 beforeEach(() => {
diff --git a/packages/jest-config/src/__tests__/resolve_config_path.test.js b/packages/jest-config/src/__tests__/resolve_config_path.test.js
index 62852aa30519..5426d7ee9051 100644
--- a/packages/jest-config/src/__tests__/resolve_config_path.test.js
+++ b/packages/jest-config/src/__tests__/resolve_config_path.test.js
@@ -8,13 +8,14 @@
  * @flow
  */
 
-import {cleanup, writeFiles} from '../../../../integration_tests/utils';
 import os from 'os';
 import path from 'path';
 import resolveConfigPath from '../resolve_config_path';
 
 import skipOnWindows from '../../../../scripts/skip_on_windows';
 
+const {cleanup, writeFiles} = require('../../../../integration_tests/utils');
+
 skipOnWindows.suite();
 
 const DIR = path.resolve(os.tmpdir(), 'resolve_config_path_test');
diff --git a/packages/jest-config/src/__tests__/set_from_argv.test.js b/packages/jest-config/src/__tests__/set_from_argv.test.js
index 8963af21876a..9b1384bd7253 100644
--- a/packages/jest-config/src/__tests__/set_from_argv.test.js
+++ b/packages/jest-config/src/__tests__/set_from_argv.test.js
@@ -6,9 +6,8 @@
  * of patent rights can be found in the PATENTS file in the same directory.
  *
  */
-'use strict';
 
-const setFromArgv = require('../set_from_argv');
+import setFromArgv from '../set_from_argv';
 
 test('maps special values to valid options', () => {
   const options = {};
diff --git a/packages/jest-config/src/__tests__/validate_pattern.test.js b/packages/jest-config/src/__tests__/validate_pattern.test.js
index 19befc8a4db9..35268412f516 100644
--- a/packages/jest-config/src/__tests__/validate_pattern.test.js
+++ b/packages/jest-config/src/__tests__/validate_pattern.test.js
@@ -7,9 +7,7 @@
  *
  */
 
-'use strict';
-
-const validatePattern = require('../validate_pattern');
+import validatePattern from '../validate_pattern';
 
 describe('validate pattern function', () => {
   it('without passed args returns true', () => {
diff --git a/packages/jest-config/src/constants.js b/packages/jest-config/src/constants.js
index 3f62a61958c1..1828ab6c28df 100644
--- a/packages/jest-config/src/constants.js
+++ b/packages/jest-config/src/constants.js
@@ -10,8 +10,8 @@
 
 import path from 'path';
 
-exports.NODE_MODULES = path.sep + 'node_modules' + path.sep;
-exports.DEFAULT_JS_PATTERN = '^.+\\.jsx?$';
-exports.DEFAULT_REPORTER_LABEL = 'default';
-exports.PACKAGE_JSON = 'package.json';
-exports.JEST_CONFIG = 'jest.config.js';
+export const NODE_MODULES = path.sep + 'node_modules' + path.sep;
+export const DEFAULT_JS_PATTERN = '^.+\\.jsx?$';
+export const DEFAULT_REPORTER_LABEL = 'default';
+export const PACKAGE_JSON = 'package.json';
+export const JEST_CONFIG = 'jest.config.js';
diff --git a/packages/jest-config/src/defaults.js b/packages/jest-config/src/defaults.js
index df42c47356d4..f5253396893c 100644
--- a/packages/jest-config/src/defaults.js
+++ b/packages/jest-config/src/defaults.js
@@ -13,9 +13,9 @@ import type {DefaultOptions} from 'types/Config';
 import os from 'os';
 import path from 'path';
 import {replacePathSepForRegex} from 'jest-regex-util';
-import constants from './constants';
+import {NODE_MODULES} from './constants';
 
-const NODE_MODULES_REGEXP = replacePathSepForRegex(constants.NODE_MODULES);
+const NODE_MODULES_REGEXP = replacePathSepForRegex(NODE_MODULES);
 
 const cacheDirectory = (() => {
   const {getuid} = process;
@@ -28,7 +28,7 @@ const cacheDirectory = (() => {
   return path.join(os.tmpdir(), 'jest_' + getuid.call(process).toString(36));
 })();
 
-module.exports = ({
+export default ({
   automock: false,
   bail: false,
   browser: false,
diff --git a/packages/jest-config/src/deprecated.js b/packages/jest-config/src/deprecated.js
index 85b203adf395..df286adc62fd 100644
--- a/packages/jest-config/src/deprecated.js
+++ b/packages/jest-config/src/deprecated.js
@@ -13,7 +13,7 @@ import prettyFormat from 'pretty-format';
 
 const format = (value: mixed) => prettyFormat(value, {min: true});
 
-const deprecatedOptions = {
+export default {
   preprocessorIgnorePatterns: (options: {
     preprocessorIgnorePatterns: Array<string>,
   }) => `  Option ${chalk.bold(
@@ -62,5 +62,3 @@ const deprecatedOptions = {
   Please update your configuration.
   `,
 };
-
-module.exports = deprecatedOptions;
diff --git a/packages/jest-config/src/get_max_workers.js b/packages/jest-config/src/get_max_workers.js
index 617077f5618b..1a9a9da8f3f4 100644
--- a/packages/jest-config/src/get_max_workers.js
+++ b/packages/jest-config/src/get_max_workers.js
@@ -12,7 +12,7 @@ import type {Argv} from 'types/Argv';
 
 import os from 'os';
 
-const getMaxWorkers = (argv: Argv): number => {
+export default function getMaxWorkers(argv: Argv): number {
   if (argv.runInBand) {
     return 1;
   } else if (argv.maxWorkers) {
@@ -21,6 +21,4 @@ const getMaxWorkers = (argv: Argv): number => {
     const cpus = os.cpus().length;
     return Math.max(argv.watch ? Math.floor(cpus / 2) : cpus - 1, 1);
   }
-};
-
-module.exports = getMaxWorkers;
+}
diff --git a/packages/jest-config/src/normalize.js b/packages/jest-config/src/normalize.js
index fa359ac8fb93..6c18c9a927b2 100644
--- a/packages/jest-config/src/normalize.js
+++ b/packages/jest-config/src/normalize.js
@@ -20,7 +20,7 @@ import {clearLine} from 'jest-util';
 import chalk from 'chalk';
 import getMaxWorkers from './get_max_workers';
 import Resolver from 'jest-resolve';
-import utils from 'jest-regex-util';
+import {replacePathSepForRegex} from 'jest-regex-util';
 import {
   BULLET,
   DOCUMENTATION_NOTE,
@@ -169,9 +169,7 @@ const normalizeUnmockedModulePathPatterns = (
   // For patterns, direct global substitution is far more ideal, so we
   // special case substitutions for patterns here.
   return options[key].map(pattern =>
-    utils.replacePathSepForRegex(
-      pattern.replace(/<rootDir>/g, options.rootDir),
-    ),
+    replacePathSepForRegex(pattern.replace(/<rootDir>/g, options.rootDir)),
   );
 };
 
@@ -309,7 +307,7 @@ const showTestPathPatternError = (testPathPattern: string) => {
   );
 };
 
-function normalize(options: InitialOptions, argv: Argv) {
+export default function normalize(options: InitialOptions, argv: Argv) {
   const {hasDeprecationWarnings} = validate(options, {
     comment: DOCUMENTATION_NOTE,
     deprecatedConfig: DEPRECATED_CONFIG,
@@ -546,5 +544,3 @@ function normalize(options: InitialOptions, argv: Argv) {
     options: newOptions,
   };
 }
-
-module.exports = normalize;
diff --git a/packages/jest-config/src/read_config_file_and_set_root_dir.js b/packages/jest-config/src/read_config_file_and_set_root_dir.js
index ddc161370b19..4b5b8675dc1b 100644
--- a/packages/jest-config/src/read_config_file_and_set_root_dir.js
+++ b/packages/jest-config/src/read_config_file_and_set_root_dir.js
@@ -18,7 +18,7 @@ import {PACKAGE_JSON} from './constants';
 // Read the configuration and set its `rootDir`
 // 1. If it's a `package.json` file, we look into its "jest" property
 // 2. For any other file, we just require it.
-module.exports = (configPath: Path): InitialOptions => {
+export default (configPath: Path): InitialOptions => {
   const isJSON = configPath.endsWith('.json');
   let configObject;
 
diff --git a/packages/jest-config/src/reporter_validation_errors.js b/packages/jest-config/src/reporter_validation_errors.js
index e0e9e5e7fe56..f7dfc629c001 100644
--- a/packages/jest-config/src/reporter_validation_errors.js
+++ b/packages/jest-config/src/reporter_validation_errors.js
@@ -25,7 +25,7 @@ const ERROR = `${BULLET}Reporter Validation Error`;
  * merged with jest-validate. Till then, we can make use of it. It works
  * and that's what counts most at this time.
  */
-function createReporterError(
+export function createReporterError(
   reporterIndex: number,
   reporterValue: Array<ReporterConfig> | string,
 ): ValidationError {
@@ -38,7 +38,7 @@ function createReporterError(
   return new ValidationError(ERROR, errorMessage, DOCUMENTATION_NOTE);
 }
 
-function createArrayReporterError(
+export function createArrayReporterError(
   arrayReporter: ReporterConfig,
   reporterIndex: number,
   valueIndex: number,
@@ -63,7 +63,7 @@ function createArrayReporterError(
   return new ValidationError(ERROR, errorMessage, DOCUMENTATION_NOTE);
 }
 
-function validateReporters(
+export function validateReporters(
   reporterConfig: Array<ReporterConfig | string>,
 ): boolean {
   return reporterConfig.every((reporter, index) => {
@@ -102,9 +102,3 @@ function validateArrayReporter(
     );
   }
 }
-
-module.exports = {
-  createArrayReporterError,
-  createReporterError,
-  validateReporters,
-};
diff --git a/packages/jest-config/src/resolve_config_path.js b/packages/jest-config/src/resolve_config_path.js
index 0898ea704e98..80f88fda153b 100644
--- a/packages/jest-config/src/resolve_config_path.js
+++ b/packages/jest-config/src/resolve_config_path.js
@@ -17,7 +17,7 @@ import {JEST_CONFIG, PACKAGE_JSON} from './constants';
 const isFile = filePath =>
   fs.existsSync(filePath) && !fs.lstatSync(filePath).isDirectory();
 
-module.exports = (pathToResolve: Path, cwd: Path): Path => {
+export default (pathToResolve: Path, cwd: Path): Path => {
   if (!path.isAbsolute(cwd)) {
     throw new Error(`"cwd" must be an absolute path. cwd: ${cwd}`);
   }
diff --git a/packages/jest-config/src/set_from_argv.js b/packages/jest-config/src/set_from_argv.js
index 45dac6088130..abfc4a8e337c 100644
--- a/packages/jest-config/src/set_from_argv.js
+++ b/packages/jest-config/src/set_from_argv.js
@@ -14,7 +14,10 @@ import type {Argv} from 'types/Argv';
 const specialArgs = ['_', '$0', 'h', 'help', 'config'];
 import {isJSONString} from './utils';
 
-function setFromArgv(options: InitialOptions, argv: Argv): InitialOptions {
+export default function setFromArgv(
+  options: InitialOptions,
+  argv: Argv,
+): InitialOptions {
   const argvToOptions = Object.keys(argv)
     .filter(key => argv[key] !== undefined && specialArgs.indexOf(key) === -1)
     .reduce((options: Object, key) => {
@@ -56,5 +59,3 @@ function setFromArgv(options: InitialOptions, argv: Argv): InitialOptions {
     argvToOptions,
   );
 }
-
-module.exports = setFromArgv;
diff --git a/packages/jest-config/src/utils.js b/packages/jest-config/src/utils.js
index d617649faa5e..a58b0b6bf707 100644
--- a/packages/jest-config/src/utils.js
+++ b/packages/jest-config/src/utils.js
@@ -14,8 +14,10 @@ import path from 'path';
 import {ValidationError} from 'jest-validate';
 import Resolver from 'jest-resolve';
 import chalk from 'chalk';
-const BULLET: string = chalk.bold('\u25cf ');
-const DOCUMENTATION_NOTE = `  ${chalk.bold('Configuration Documentation:')}
+export const BULLET: string = chalk.bold('\u25cf ');
+export const DOCUMENTATION_NOTE = `  ${chalk.bold(
+  'Configuration Documentation:',
+)}
   https://facebook.github.io/jest/docs/configuration.html
 `;
 
@@ -27,7 +29,7 @@ const createValidationError = (message: string) => {
   );
 };
 
-const resolve = (rootDir: string, key: string, filePath: Path) => {
+export const resolve = (rootDir: string, key: string, filePath: Path) => {
   const module = Resolver.findNodeModule(
     _replaceRootDirInPath(rootDir, filePath),
     {
@@ -46,7 +48,10 @@ const resolve = (rootDir: string, key: string, filePath: Path) => {
   return module;
 };
 
-const _replaceRootDirInPath = (rootDir: string, filePath: Path): string => {
+export const _replaceRootDirInPath = (
+  rootDir: string,
+  filePath: Path,
+): string => {
   if (!/^<rootDir>/.test(filePath)) {
     return filePath;
   }
@@ -71,7 +76,7 @@ const _replaceRootDirInObject = (rootDir: string, config: any): Object => {
   return config;
 };
 
-const _replaceRootDirTags = (rootDir: string, config: any) => {
+export const _replaceRootDirTags = (rootDir: string, config: any) => {
   switch (typeof config) {
     case 'object':
       if (Array.isArray(config)) {
@@ -95,7 +100,7 @@ const _replaceRootDirTags = (rootDir: string, config: any) => {
  * 1. looks for <name> relative to project.
  * 1. looks for <name> relative to Jest.
  */
-const getTestEnvironment = (config: Object) => {
+export const getTestEnvironment = (config: Object) => {
   const env = config.testEnvironment;
   let module = Resolver.findNodeModule(`jest-environment-${env}`, {
     basedir: config.rootDir,
@@ -126,18 +131,8 @@ const getTestEnvironment = (config: Object) => {
   );
 };
 
-const isJSONString = (text: ?string) =>
+export const isJSONString = (text: ?string) =>
   text &&
   typeof text === 'string' &&
   text.startsWith('{') &&
   text.endsWith('}');
-
-module.exports = {
-  BULLET,
-  DOCUMENTATION_NOTE,
-  _replaceRootDirInPath,
-  _replaceRootDirTags,
-  getTestEnvironment,
-  isJSONString,
-  resolve,
-};
diff --git a/packages/jest-config/src/valid_config.js b/packages/jest-config/src/valid_config.js
index 8a902261d950..17967a14fd84 100644
--- a/packages/jest-config/src/valid_config.js
+++ b/packages/jest-config/src/valid_config.js
@@ -11,11 +11,11 @@
 import type {InitialOptions} from 'types/Config';
 
 import {replacePathSepForRegex} from 'jest-regex-util';
-import constants from './constants';
+import {NODE_MODULES} from './constants';
 
-const NODE_MODULES_REGEXP = replacePathSepForRegex(constants.NODE_MODULES);
+const NODE_MODULES_REGEXP = replacePathSepForRegex(NODE_MODULES);
 
-module.exports = ({
+export default ({
   automock: false,
   bail: false,
   browser: false,
diff --git a/packages/jest-config/src/validate_pattern.js b/packages/jest-config/src/validate_pattern.js
index 21dfaf39fa0b..56d9455af91a 100644
--- a/packages/jest-config/src/validate_pattern.js
+++ b/packages/jest-config/src/validate_pattern.js
@@ -8,7 +8,7 @@
  * @flow
  */
 
-const validatePattern = (pattern: string) => {
+export default function validatePattern(pattern: string) {
   if (pattern) {
     try {
       // eslint-disable-next-line no-new
@@ -19,6 +19,4 @@ const validatePattern = (pattern: string) => {
   }
 
   return true;
-};
-
-module.exports = validatePattern;
+}
diff --git a/packages/jest-diff/src/constants.js b/packages/jest-diff/src/constants.js
index 9c41e0883686..0ed18e7684d3 100644
--- a/packages/jest-diff/src/constants.js
+++ b/packages/jest-diff/src/constants.js
@@ -10,11 +10,11 @@
 
 import chalk from 'chalk';
 
-exports.NO_DIFF_MESSAGE = chalk.dim(
+export const NO_DIFF_MESSAGE = chalk.dim(
   'Compared values have no visual difference.',
 );
 
-exports.SIMILAR_MESSAGE = chalk.dim(
+export const SIMILAR_MESSAGE = chalk.dim(
   'Compared values serialize to the same structure.\n' +
     'Printing internal object structure without calling `toJSON` instead.',
 );
diff --git a/packages/jest-diff/src/diff_strings.js b/packages/jest-diff/src/diff_strings.js
index 6de3a7a9793c..c836166471c6 100644
--- a/packages/jest-diff/src/diff_strings.js
+++ b/packages/jest-diff/src/diff_strings.js
@@ -257,7 +257,7 @@ const formatHunks = (
   };
 };
 
-function diffStrings(
+export default function diffStrings(
   a: string,
   b: string,
   options: ?DiffOptions,
@@ -278,5 +278,3 @@ function diffStrings(
     return NO_DIFF_MESSAGE;
   }
 }
-
-module.exports = diffStrings;
diff --git a/packages/jest-editor-support/src/Process.js b/packages/jest-editor-support/src/Process.js
index e3c057e903af..c3bc5c1d51a5 100644
--- a/packages/jest-editor-support/src/Process.js
+++ b/packages/jest-editor-support/src/Process.js
@@ -18,7 +18,7 @@ import ProjectWorkspace from './project_workspace';
  * @param {string[]} args
  * @returns {ChildProcess}
  */
-module.exports.createProcess = (
+export const createProcess = (
   workspace: ProjectWorkspace,
   args: Array<string>,
 ): ChildProcess => {
diff --git a/packages/jest-editor-support/src/Runner.js b/packages/jest-editor-support/src/Runner.js
index 124a6c924904..6095e72e9d92 100644
--- a/packages/jest-editor-support/src/Runner.js
+++ b/packages/jest-editor-support/src/Runner.js
@@ -20,7 +20,7 @@ import {createProcess} from './Process';
 // This class represents the running process, and
 // passes out events when it understands what data is being
 // pass sent out of the process
-module.exports = class Runner extends EventEmitter {
+export default class Runner extends EventEmitter {
   debugprocess: ChildProcess;
   outputPath: string;
   workspace: ProjectWorkspace;
@@ -108,4 +108,4 @@ module.exports = class Runner extends EventEmitter {
     }
     delete this.debugprocess;
   }
-};
+}
diff --git a/packages/jest-editor-support/src/Settings.js b/packages/jest-editor-support/src/Settings.js
index 13bf571b8939..7d5a747011ba 100644
--- a/packages/jest-editor-support/src/Settings.js
+++ b/packages/jest-editor-support/src/Settings.js
@@ -33,7 +33,7 @@ type ConfigRepresentation = {
   testMatch: Array<Glob>,
 };
 
-module.exports = class Settings extends EventEmitter {
+export default class Settings extends EventEmitter {
   getConfigProcess: ChildProcess;
   jestVersionMajor: number | null;
   _createProcess: (
@@ -76,4 +76,4 @@ module.exports = class Settings extends EventEmitter {
       completed();
     });
   }
-};
+}
diff --git a/packages/jest-editor-support/src/__tests__/project_workspace.test.js b/packages/jest-editor-support/src/__tests__/project_workspace.test.js
index 9c1cdbebe8ba..03f0412940c0 100644
--- a/packages/jest-editor-support/src/__tests__/project_workspace.test.js
+++ b/packages/jest-editor-support/src/__tests__/project_workspace.test.js
@@ -10,7 +10,7 @@
 
 'use strict';
 
-const ProjectWorkspace = require('../project_workspace');
+import ProjectWorkspace from '../project_workspace';
 
 describe('setup', () => {
   it('sets itself up fom the constructor', () => {
diff --git a/packages/jest-editor-support/src/__tests__/runner.test.js b/packages/jest-editor-support/src/__tests__/runner.test.js
index aec8d4aa8bef..7c1146954e85 100644
--- a/packages/jest-editor-support/src/__tests__/runner.test.js
+++ b/packages/jest-editor-support/src/__tests__/runner.test.js
@@ -14,7 +14,7 @@ const {EventEmitter} = require('events');
 const path = require('path');
 const {readFileSync} = require('fs');
 const fixtures = path.resolve(__dirname, '../../../../fixtures');
-const ProjectWorkspace = require('../project_workspace');
+import ProjectWorkspace from '../project_workspace';
 
 // Replace `readFile` with `readFileSync` so we don't get multiple threads
 jest.doMock('fs', () => {
@@ -36,7 +36,7 @@ jest.doMock('../Process.js', () => {
   };
 });
 
-const Runner = require('../Runner');
+const Runner = require('../Runner').default;
 
 describe('events', () => {
   let runner;
diff --git a/packages/jest-editor-support/src/__tests__/settings.test.js b/packages/jest-editor-support/src/__tests__/settings.test.js
index 659218b52f06..bff0eef30faa 100644
--- a/packages/jest-editor-support/src/__tests__/settings.test.js
+++ b/packages/jest-editor-support/src/__tests__/settings.test.js
@@ -10,9 +10,9 @@
 
 'use strict';
 
-const {EventEmitter} = require('events');
-const ProjectWorkspace = require('../project_workspace');
-const Settings = require('../Settings');
+import EventEmitter from 'events';
+import ProjectWorkspace from '../project_workspace';
+import Settings from '../Settings';
 
 describe('Settings', () => {
   it('sets itself up fom the constructor', () => {
diff --git a/packages/jest-editor-support/src/__tests__/test_reconciler.test.js b/packages/jest-editor-support/src/__tests__/test_reconciler.test.js
index a119a7f70aad..b419b1c67d22 100644
--- a/packages/jest-editor-support/src/__tests__/test_reconciler.test.js
+++ b/packages/jest-editor-support/src/__tests__/test_reconciler.test.js
@@ -8,9 +8,10 @@
  * @flow
  */
 
-const fs = require('fs');
-const path = require('path');
-const TestReconciler = require('../test_reconciler');
+import fs from 'fs';
+import path from 'path';
+import TestReconciler from '../test_reconciler';
+
 const fixtures = path.resolve(__dirname, '../../../../fixtures');
 
 const reconcilerWithFile = (file: string): TestReconciler => {
diff --git a/packages/jest-editor-support/src/index.js b/packages/jest-editor-support/src/index.js
index 4da897cc71a4..ebcd12556f54 100644
--- a/packages/jest-editor-support/src/index.js
+++ b/packages/jest-editor-support/src/index.js
@@ -8,7 +8,7 @@
  * @flow
  */
 
-import Process from './Process';
+import * as Process from './Process';
 
 import ProjectWorkspace from './project_workspace';
 import Runner from './Runner';
diff --git a/packages/jest-editor-support/src/parsers/babylon_parser.js b/packages/jest-editor-support/src/parsers/babylon_parser.js
index a48efe010b1f..79fc62ee249f 100644
--- a/packages/jest-editor-support/src/parsers/babylon_parser.js
+++ b/packages/jest-editor-support/src/parsers/babylon_parser.js
@@ -18,7 +18,7 @@ export type BabylonParserResult = {
   itBlocks: Array<ItBlock>,
 };
 
-const parse = (file: string): BabylonParserResult => {
+export const parse = (file: string): BabylonParserResult => {
   const itBlocks: ItBlock[] = [];
   const expects: Expect[] = [];
 
@@ -173,7 +173,3 @@ const parse = (file: string): BabylonParserResult => {
     itBlocks,
   };
 };
-
-module.exports = {
-  parse,
-};
diff --git a/packages/jest-editor-support/src/parsers/parser_nodes.js b/packages/jest-editor-support/src/parsers/parser_nodes.js
index 931f76e4ab6f..9f0f2f565702 100644
--- a/packages/jest-editor-support/src/parsers/parser_nodes.js
+++ b/packages/jest-editor-support/src/parsers/parser_nodes.js
@@ -10,20 +10,14 @@
 
 import type {Location} from '../types';
 
-class Node {
+export class Node {
   start: Location;
   end: Location;
   file: string;
 }
 
-class Expect extends Node {}
+export class Expect extends Node {}
 
-class ItBlock extends Node {
+export class ItBlock extends Node {
   name: string;
 }
-
-module.exports = {
-  Expect,
-  ItBlock,
-  Node,
-};
diff --git a/packages/jest-editor-support/src/project_workspace.js b/packages/jest-editor-support/src/project_workspace.js
index 3ab415de715f..cdb6b79760fc 100644
--- a/packages/jest-editor-support/src/project_workspace.js
+++ b/packages/jest-editor-support/src/project_workspace.js
@@ -11,7 +11,7 @@
 /**
  * Represents the project that the extension is running on and it's state
  */
-module.exports = class ProjectWorkspace {
+export default class ProjectWorkspace {
   /**
    * The path to the root of the project's workspace
    *
@@ -58,4 +58,4 @@ module.exports = class ProjectWorkspace {
     this.pathToConfig = pathToConfig;
     this.localJestMajorVersion = localJestMajorVersion;
   }
-};
+}
diff --git a/packages/jest-editor-support/src/test_reconciler.js b/packages/jest-editor-support/src/test_reconciler.js
index af9bbd06680c..51a07fff3769 100644
--- a/packages/jest-editor-support/src/test_reconciler.js
+++ b/packages/jest-editor-support/src/test_reconciler.js
@@ -28,8 +28,7 @@ import path from 'path';
  *  This class represents the state between runs, keeping track of passes/fails
  *  at a file level, generating useful error messages and providing a nice API.
  */
-
-module.exports = class TestReconciler {
+export default class TestReconciler {
   fileStatuses: any;
   fails: Array<TestFileAssertionStatus>;
   passes: Array<TestFileAssertionStatus>;
@@ -178,4 +177,4 @@ module.exports = class TestReconciler {
     }
     return assertion;
   }
-};
+}
diff --git a/packages/jest-haste-map/src/__tests__/get_mock_name.test.js b/packages/jest-haste-map/src/__tests__/get_mock_name.test.js
index 087f0527d382..210b132e7d48 100644
--- a/packages/jest-haste-map/src/__tests__/get_mock_name.test.js
+++ b/packages/jest-haste-map/src/__tests__/get_mock_name.test.js
@@ -8,8 +8,8 @@
  */
 'use strict';
 
-const path = require('path');
-const getMockName = require('../get_mock_name');
+import path from 'path';
+import getMockName from '../get_mock_name';
 
 describe('getMockName', () => {
   it('extracts mock name from file path', () => {
diff --git a/packages/jest-haste-map/src/__tests__/index.test.js b/packages/jest-haste-map/src/__tests__/index.test.js
index f80041f2dd8a..1a6d8aea5e91 100644
--- a/packages/jest-haste-map/src/__tests__/index.test.js
+++ b/packages/jest-haste-map/src/__tests__/index.test.js
@@ -173,7 +173,7 @@ describe('HasteMap', () => {
   });
 
   it('exports constants', () => {
-    expect(HasteMap.H).toBe(require('../constants'));
+    expect(HasteMap.H).toBe(require('../constants').default);
   });
 
   it('creates valid cache file paths', () => {
@@ -862,7 +862,9 @@ describe('HasteMap', () => {
           moduleMap.getModule('Pear');
           throw new Error('should be unreachable');
         } catch (error) {
-          const {DuplicateHasteCandidatesError} = require('../module_map');
+          const {
+            DuplicateHasteCandidatesError,
+          } = require('../module_map').default;
           expect(error).toBeInstanceOf(DuplicateHasteCandidatesError);
           expect(error.hasteName).toBe('Pear');
           expect(error.platform).toBe('g');
diff --git a/packages/jest-haste-map/src/__tests__/worker.test.js b/packages/jest-haste-map/src/__tests__/worker.test.js
index e228b86b5f1f..e8825baada30 100644
--- a/packages/jest-haste-map/src/__tests__/worker.test.js
+++ b/packages/jest-haste-map/src/__tests__/worker.test.js
@@ -9,11 +9,12 @@
 
 'use strict';
 
-const path = require('path');
-const fs = require('graceful-fs');
-const skipOnWindows = require('../../../../scripts/skip_on_windows');
+import path from 'path';
+import fs from 'graceful-fs';
+import skipOnWindows from '../../../../scripts/skip_on_windows';
+
+import H from '../constants';
 
-const H = require('../constants');
 const worker = require('../worker');
 
 let createCallback;
diff --git a/packages/jest-haste-map/src/constants.js b/packages/jest-haste-map/src/constants.js
index dc0ae320cd2a..60282f0688ca 100644
--- a/packages/jest-haste-map/src/constants.js
+++ b/packages/jest-haste-map/src/constants.js
@@ -17,7 +17,7 @@
  * This constant key map allows to keep the map smaller without having to build
  * a custom serialization library.
  */
-module.exports = {
+export default {
   /* file map attributes */
   ID: 0,
   MTIME: 1,
diff --git a/packages/jest-haste-map/src/get_mock_name.js b/packages/jest-haste-map/src/get_mock_name.js
index 650f29e7a393..6431f5830e58 100644
--- a/packages/jest-haste-map/src/get_mock_name.js
+++ b/packages/jest-haste-map/src/get_mock_name.js
@@ -19,4 +19,4 @@ const getMockName = (filePath: string) => {
     .replace(/\\/g, '/');
 };
 
-module.exports = getMockName;
+export default getMockName;
diff --git a/packages/jest-haste-map/src/haste_fs.js b/packages/jest-haste-map/src/haste_fs.js
index fcd12ec95d4f..2a4e202a3064 100644
--- a/packages/jest-haste-map/src/haste_fs.js
+++ b/packages/jest-haste-map/src/haste_fs.js
@@ -15,7 +15,7 @@ import path from 'path';
 import micromatch from 'micromatch';
 import H from './constants';
 
-class HasteFS {
+export default class HasteFS {
   _files: FileData;
 
   constructor(files: FileData) {
@@ -62,5 +62,3 @@ class HasteFS {
     return files;
   }
 }
-
-module.exports = HasteFS;
diff --git a/packages/jest-haste-map/src/index.js b/packages/jest-haste-map/src/index.js
index b38df77b2ce7..64c09754971b 100644
--- a/packages/jest-haste-map/src/index.js
+++ b/packages/jest-haste-map/src/index.js
@@ -37,9 +37,13 @@ import HasteFS from './haste_fs';
 import HasteModuleMap from './module_map';
 import getMockName from './get_mock_name';
 import getPlatformExtension from './lib/get_platform_extension';
-import nodeCrawl from './crawlers/node';
 import normalizePathSep from './lib/normalize_path_sep';
+
+// eslint-disable-next-line import/default
+import nodeCrawl from './crawlers/node';
+// eslint-disable-next-line import/default
 import watchmanCrawl from './crawlers/watchman';
+// eslint-disable-next-line import/default
 import worker from './worker';
 
 type Options = {
diff --git a/packages/jest-haste-map/src/lib/__tests__/extract_requires.test.js b/packages/jest-haste-map/src/lib/__tests__/extract_requires.test.js
index 60763e597089..6274948d8b97 100644
--- a/packages/jest-haste-map/src/lib/__tests__/extract_requires.test.js
+++ b/packages/jest-haste-map/src/lib/__tests__/extract_requires.test.js
@@ -10,7 +10,7 @@
  */
 'use strict';
 
-const extractRequires = require('../extract_requires');
+import extractRequires from '../extract_requires';
 
 it('extracts both requires and imports from code', () => {
   const code = `
diff --git a/packages/jest-haste-map/src/lib/__tests__/get_platform_extension.test.js b/packages/jest-haste-map/src/lib/__tests__/get_platform_extension.test.js
index e55ea88ac3f0..0db620bdab75 100644
--- a/packages/jest-haste-map/src/lib/__tests__/get_platform_extension.test.js
+++ b/packages/jest-haste-map/src/lib/__tests__/get_platform_extension.test.js
@@ -10,13 +10,9 @@
 
 'use strict';
 
-let getPlatformExtension;
+import getPlatformExtension from '../get_platform_extension';
 
 describe('getPlatformExtension', () => {
-  beforeEach(() => {
-    getPlatformExtension = require('../get_platform_extension');
-  });
-
   it('should get platform ext', () => {
     expect(getPlatformExtension('a.ios.js')).toBe('ios');
     expect(getPlatformExtension('a.android.js')).toBe('android');
diff --git a/packages/jest-haste-map/src/lib/__tests__/normalize_path_sep.test.js b/packages/jest-haste-map/src/lib/__tests__/normalize_path_sep.test.js
index 10a35aa8c188..1a8fa1b4cad8 100644
--- a/packages/jest-haste-map/src/lib/__tests__/normalize_path_sep.test.js
+++ b/packages/jest-haste-map/src/lib/__tests__/normalize_path_sep.test.js
@@ -14,14 +14,14 @@ describe('normalizePathSep', () => {
   it('does nothing on posix', () => {
     jest.resetModules();
     jest.mock('path', () => require.requireActual('path').posix);
-    const normalizePathSep = require('../normalize_path_sep');
+    const normalizePathSep = require('../normalize_path_sep').default;
     expect(normalizePathSep('foo/bar/baz.js')).toEqual('foo/bar/baz.js');
   });
 
   it('replace slashes on windows', () => {
     jest.resetModules();
     jest.mock('path', () => require.requireActual('path').win32);
-    const normalizePathSep = require('../normalize_path_sep');
+    const normalizePathSep = require('../normalize_path_sep').default;
     expect(normalizePathSep('foo/bar/baz.js')).toEqual('foo\\bar\\baz.js');
   });
 });
diff --git a/packages/jest-haste-map/src/lib/extract_requires.js b/packages/jest-haste-map/src/lib/extract_requires.js
index 7cd916b99852..605d93fc446f 100644
--- a/packages/jest-haste-map/src/lib/extract_requires.js
+++ b/packages/jest-haste-map/src/lib/extract_requires.js
@@ -18,7 +18,7 @@ const replacePatterns = {
   REQUIRE_RE: /(?:^|[^.]\s*)(\brequire\s*?\(\s*?)([`'"])([^`'"]+)(\2\s*?\))/g,
 };
 
-function extractRequires(code: string): Array<string> {
+export default function extractRequires(code: string): Array<string> {
   const dependencies = new Set();
   const addDependency = (match, pre, quot, dep, post) => {
     dependencies.add(dep);
@@ -35,5 +35,3 @@ function extractRequires(code: string): Array<string> {
 
   return Array.from(dependencies);
 }
-
-module.exports = extractRequires;
diff --git a/packages/jest-haste-map/src/lib/get_platform_extension.js b/packages/jest-haste-map/src/lib/get_platform_extension.js
index c7f6a69a816e..61edd8c78303 100644
--- a/packages/jest-haste-map/src/lib/get_platform_extension.js
+++ b/packages/jest-haste-map/src/lib/get_platform_extension.js
@@ -16,7 +16,7 @@ const SUPPORTED_PLATFORM_EXTS = {
 };
 
 // Extract platform extension: index.ios.js -> ios
-function getPlatformExtension(
+export default function getPlatformExtension(
   file: string,
   platforms?: Array<string>,
 ): ?string {
@@ -33,5 +33,3 @@ function getPlatformExtension(
   }
   return SUPPORTED_PLATFORM_EXTS[platform] ? platform : null;
 }
-
-module.exports = getPlatformExtension;
diff --git a/packages/jest-haste-map/src/lib/normalize_path_sep.js b/packages/jest-haste-map/src/lib/normalize_path_sep.js
index abd3eb06ea21..801429d60509 100644
--- a/packages/jest-haste-map/src/lib/normalize_path_sep.js
+++ b/packages/jest-haste-map/src/lib/normalize_path_sep.js
@@ -11,10 +11,10 @@
 const path = require('path');
 
 let normalizePathSep;
-if (path.sep == '/') {
+if (path.sep === '/') {
   normalizePathSep = (filePath: string) => filePath;
 } else {
   normalizePathSep = (filePath: string) => filePath.replace(/\//g, path.sep);
 }
 
-module.exports = normalizePathSep;
+export default normalizePathSep;
diff --git a/packages/jest-haste-map/src/module_map.js b/packages/jest-haste-map/src/module_map.js
index 19228f9ff148..8fb62f91e8a5 100644
--- a/packages/jest-haste-map/src/module_map.js
+++ b/packages/jest-haste-map/src/module_map.js
@@ -20,7 +20,7 @@ import H from './constants';
 
 const EMPTY_MAP = {};
 
-class ModuleMap {
+export default class ModuleMap {
   _raw: RawModuleMap;
   static DuplicateHasteCandidatesError: Class<DuplicateHasteCandidatesError>;
 
@@ -187,4 +187,3 @@ function getTypeMessage(type: number) {
 }
 
 ModuleMap.DuplicateHasteCandidatesError = DuplicateHasteCandidatesError;
-module.exports = ModuleMap;
diff --git a/packages/jest-haste-map/src/worker.js b/packages/jest-haste-map/src/worker.js
index 9bf52cb3968f..451f2ee36eaa 100644
--- a/packages/jest-haste-map/src/worker.js
+++ b/packages/jest-haste-map/src/worker.js
@@ -40,6 +40,7 @@ const formatError = (error: string | Error): SerializableError => {
   };
 };
 
+// Cannot be ESM export or worker-farm is confused
 module.exports = (data: WorkerMessage, callback: WorkerCallback): void => {
   if (
     data.hasteImplModulePath &&
diff --git a/packages/jest-jasmine2/src/__tests__/expectation_result_factory.test.js b/packages/jest-jasmine2/src/__tests__/expectation_result_factory.test.js
index 795e16a96a91..3eb9381745c6 100644
--- a/packages/jest-jasmine2/src/__tests__/expectation_result_factory.test.js
+++ b/packages/jest-jasmine2/src/__tests__/expectation_result_factory.test.js
@@ -9,7 +9,7 @@
 
 'use strict';
 
-const expectationResultFactory = require('../expectation_result_factory');
+import expectationResultFactory from '../expectation_result_factory';
 
 describe('expectationResultFactory', () => {
   it('returns the result if passed.', () => {
diff --git a/packages/jest-jasmine2/src/__tests__/p_timeout.test.js b/packages/jest-jasmine2/src/__tests__/p_timeout.test.js
index 2d4d7e3f3cfb..a98ded5aa91b 100644
--- a/packages/jest-jasmine2/src/__tests__/p_timeout.test.js
+++ b/packages/jest-jasmine2/src/__tests__/p_timeout.test.js
@@ -11,7 +11,7 @@
 
 jest.useFakeTimers();
 
-const pTimeout = require('../p_timeout');
+import pTimeout from '../p_timeout';
 
 describe('pTimeout', () => {
   it('calls `clearTimeout` and resolves when `promise` resolves.', async () => {
diff --git a/packages/jest-jasmine2/src/__tests__/queue_runner.test.js b/packages/jest-jasmine2/src/__tests__/queue_runner.test.js
index 8e2a5f717863..93d543ef5f55 100644
--- a/packages/jest-jasmine2/src/__tests__/queue_runner.test.js
+++ b/packages/jest-jasmine2/src/__tests__/queue_runner.test.js
@@ -9,7 +9,7 @@
 
 'use strict';
 
-const queueRunner = require('../queue_runner');
+import queueRunner from '../queue_runner';
 
 describe('queueRunner', () => {
   it('runs every function in the queue.', async () => {
diff --git a/packages/jest-jasmine2/src/__tests__/reporter.test.js b/packages/jest-jasmine2/src/__tests__/reporter.test.js
index a70bcfa1fbd4..f6e407d91fc7 100644
--- a/packages/jest-jasmine2/src/__tests__/reporter.test.js
+++ b/packages/jest-jasmine2/src/__tests__/reporter.test.js
@@ -9,7 +9,7 @@
 
 'use strict';
 
-const JasmineReporter = require('../reporter');
+import JasmineReporter from '../reporter';
 
 describe('Jasmine2Reporter', () => {
   let reporter;
diff --git a/packages/jest-jasmine2/src/assert_support.js b/packages/jest-jasmine2/src/assert_support.js
index 1062fec7b1bc..59e41f2d9ede 100644
--- a/packages/jest-jasmine2/src/assert_support.js
+++ b/packages/jest-jasmine2/src/assert_support.js
@@ -133,4 +133,4 @@ function assertionErrorMessage(error: AssertionError, options: DiffOptions) {
   );
 }
 
-module.exports = assertionErrorMessage;
+export default assertionErrorMessage;
diff --git a/packages/jest-jasmine2/src/expectation_failed.js b/packages/jest-jasmine2/src/expectation_failed.js
index bae98e225a89..6fcbab74f219 100644
--- a/packages/jest-jasmine2/src/expectation_failed.js
+++ b/packages/jest-jasmine2/src/expectation_failed.js
@@ -8,6 +8,4 @@
  * @flow
  */
 
-class ExpectationFailed extends Error {}
-
-module.exports = ExpectationFailed;
+export default class ExpectationFailed extends Error {}
diff --git a/packages/jest-jasmine2/src/expectation_result_factory.js b/packages/jest-jasmine2/src/expectation_result_factory.js
index 5604d208e94c..40481f54cc01 100644
--- a/packages/jest-jasmine2/src/expectation_result_factory.js
+++ b/packages/jest-jasmine2/src/expectation_result_factory.js
@@ -40,7 +40,7 @@ type Options = {
   message?: string,
 };
 
-function expectationResultFactory(options: Options) {
+export default function expectationResultFactory(options: Options) {
   const message = messageFormatter(options);
   const stack = stackFormatter(options, message);
 
@@ -64,5 +64,3 @@ function expectationResultFactory(options: Options) {
     stack,
   };
 }
-
-module.exports = expectationResultFactory;
diff --git a/packages/jest-jasmine2/src/index.js b/packages/jest-jasmine2/src/index.js
index c85402ddca1f..75f50a06b320 100644
--- a/packages/jest-jasmine2/src/index.js
+++ b/packages/jest-jasmine2/src/index.js
@@ -17,7 +17,7 @@ import type Runtime from 'jest-runtime';
 
 import path from 'path';
 import JasmineReporter from './reporter';
-import jasmineAsync from './jasmine_async';
+import {install as jasmineAsyncInstall} from './jasmine_async';
 
 const JASMINE = require.resolve('./jasmine/jasmine_light.js');
 
@@ -42,7 +42,7 @@ async function jasmine2(
   Object.assign(environment.global, jasmineInterface);
   env.addReporter(jasmineInterface.jsApiReporter);
 
-  jasmineAsync.install(environment.global);
+  jasmineAsyncInstall(environment.global);
 
   environment.global.test = environment.global.it;
   environment.global.it.only = environment.global.fit;
@@ -75,18 +75,20 @@ async function jasmine2(
 
   env.addReporter(reporter);
 
-  runtime.requireInternalModule(path.resolve(__dirname, './jest_expect.js'))({
-    expand: globalConfig.expand,
-  });
-
-  const snapshotState: SnapshotState = runtime.requireInternalModule(
-    path.resolve(__dirname, './setup_jest_globals.js'),
-  )({
-    config,
-    globalConfig,
-    localRequire: runtime.requireModule.bind(runtime),
-    testPath,
-  });
+  runtime
+    .requireInternalModule(path.resolve(__dirname, './jest_expect.js'))
+    .default({
+      expand: globalConfig.expand,
+    });
+
+  const snapshotState: SnapshotState = runtime
+    .requireInternalModule(path.resolve(__dirname, './setup_jest_globals.js'))
+    .default({
+      config,
+      globalConfig,
+      localRequire: runtime.requireModule.bind(runtime),
+      testPath,
+    });
 
   if (config.setupTestFrameworkScriptFile) {
     runtime.requireModule(config.setupTestFrameworkScriptFile);
diff --git a/packages/jest-jasmine2/src/jasmine/Env.js b/packages/jest-jasmine2/src/jasmine/Env.js
index 3b885618b8a6..689437a7f7be 100644
--- a/packages/jest-jasmine2/src/jasmine/Env.js
+++ b/packages/jest-jasmine2/src/jasmine/Env.js
@@ -35,7 +35,7 @@ import queueRunner from '../queue_runner';
 
 import treeProcessor from '../tree_processor';
 
-module.exports = function(j$) {
+export default function(j$) {
   function Env(options) {
     options = options || {};
 
@@ -520,4 +520,4 @@ module.exports = function(j$) {
   }
 
   return Env;
-};
+}
diff --git a/packages/jest-jasmine2/src/jasmine/Spec.js b/packages/jest-jasmine2/src/jasmine/Spec.js
index 9b7b92599268..a8da65d5c386 100644
--- a/packages/jest-jasmine2/src/jasmine/Spec.js
+++ b/packages/jest-jasmine2/src/jasmine/Spec.js
@@ -36,7 +36,7 @@ import ExpectationFailed from '../expectation_failed';
 
 import expectationResultFactory from '../expectation_result_factory';
 
-function Spec(attrs: Object) {
+export default function Spec(attrs: Object) {
   this.resultCallback = attrs.resultCallback || function() {};
   this.id = attrs.id;
   this.description = attrs.description || '';
@@ -133,7 +133,7 @@ Spec.prototype.onException = function onException(error) {
   }
 
   if (error instanceof require('assert').AssertionError) {
-    const assertionErrorMessage = require('../assert_support');
+    const assertionErrorMessage = require('../assert_support').default;
     error = assertionErrorMessage(error, {expand: this.expand});
   }
 
@@ -210,5 +210,3 @@ Spec.isPendingSpecException = function(e) {
     e.toString().indexOf(Spec.pendingSpecExceptionMessage) !== -1
   );
 };
-
-module.exports = Spec;
diff --git a/packages/jest-jasmine2/src/jasmine/Suite.js b/packages/jest-jasmine2/src/jasmine/Suite.js
index 8d511602c58a..ac2380782dab 100644
--- a/packages/jest-jasmine2/src/jasmine/Suite.js
+++ b/packages/jest-jasmine2/src/jasmine/Suite.js
@@ -36,7 +36,7 @@ import ExpectationFailed from '../expectation_failed';
 
 import expectationResultFactory from '../expectation_result_factory';
 
-function Suite(attrs: Object) {
+export default function Suite(attrs: Object) {
   this.id = attrs.id;
   this.parentSuite = attrs.parentSuite;
   this.description = attrs.description;
@@ -189,5 +189,3 @@ function isAfterAll(children) {
 function isFailure(args) {
   return !args[0];
 }
-
-module.exports = Suite;
diff --git a/packages/jest-jasmine2/src/jasmine/Timer.js b/packages/jest-jasmine2/src/jasmine/Timer.js
index 038b3c3013ef..6a50d3784496 100644
--- a/packages/jest-jasmine2/src/jasmine/Timer.js
+++ b/packages/jest-jasmine2/src/jasmine/Timer.js
@@ -38,7 +38,7 @@ const defaultNow = (function(Date) {
   };
 })(Date);
 
-function Timer(options: Object) {
+export default function Timer(options: Object) {
   options = options || {};
 
   const now = options.now || defaultNow;
@@ -52,5 +52,3 @@ function Timer(options: Object) {
     return now() - startTime;
   };
 }
-
-module.exports = Timer;
diff --git a/packages/jest-jasmine2/src/jasmine/call_tracker.js b/packages/jest-jasmine2/src/jasmine/call_tracker.js
index fdd84e232cd2..364f446ad597 100644
--- a/packages/jest-jasmine2/src/jasmine/call_tracker.js
+++ b/packages/jest-jasmine2/src/jasmine/call_tracker.js
@@ -78,4 +78,4 @@ function CallTracker() {
   };
 }
 
-module.exports = CallTracker;
+export default CallTracker;
diff --git a/packages/jest-jasmine2/src/jasmine/create_spy.js b/packages/jest-jasmine2/src/jasmine/create_spy.js
index d3f93ad8e2d2..ca89affbcdd8 100644
--- a/packages/jest-jasmine2/src/jasmine/create_spy.js
+++ b/packages/jest-jasmine2/src/jasmine/create_spy.js
@@ -74,4 +74,4 @@ function createSpy(name, originalFn) {
   return spy;
 }
 
-module.exports = createSpy;
+export default createSpy;
diff --git a/packages/jest-jasmine2/src/jasmine/jasmine_light.js b/packages/jest-jasmine2/src/jasmine/jasmine_light.js
index 8d1da92f4686..8102c8bb43fa 100644
--- a/packages/jest-jasmine2/src/jasmine/jasmine_light.js
+++ b/packages/jest-jasmine2/src/jasmine/jasmine_light.js
@@ -43,7 +43,7 @@ import SpyRegistry from './spy_registry';
 import Suite from './Suite';
 import Timer from './Timer';
 
-exports.create = function() {
+export const create = function() {
   const j$ = {};
 
   j$.DEFAULT_TIMEOUT_INTERVAL = 5000;
@@ -66,6 +66,7 @@ exports.create = function() {
   return j$;
 };
 
+// Interface is a reserved word in strict mode, so can't export it as ESM
 exports.interface = function(jasmine: Jasmine, env: any) {
   const jasmineInterface = {
     describe(description: string, specDefinitions: Function) {
diff --git a/packages/jest-jasmine2/src/jasmine/js_api_reporter.js b/packages/jest-jasmine2/src/jasmine/js_api_reporter.js
index 2dfef1a30e8f..502f0459823e 100644
--- a/packages/jest-jasmine2/src/jasmine/js_api_reporter.js
+++ b/packages/jest-jasmine2/src/jasmine/js_api_reporter.js
@@ -39,7 +39,7 @@ const noopTimer = {
   },
 };
 
-function JsApiReporter(options: Object) {
+export default function JsApiReporter(options: Object) {
   const timer = options.timer || noopTimer;
   let status = 'loaded';
 
@@ -108,5 +108,3 @@ function JsApiReporter(options: Object) {
     return executionTime;
   };
 }
-
-module.exports = JsApiReporter;
diff --git a/packages/jest-jasmine2/src/jasmine/report_dispatcher.js b/packages/jest-jasmine2/src/jasmine/report_dispatcher.js
index 9e56c22e5707..aa86ed93f599 100644
--- a/packages/jest-jasmine2/src/jasmine/report_dispatcher.js
+++ b/packages/jest-jasmine2/src/jasmine/report_dispatcher.js
@@ -32,7 +32,7 @@ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 /* @flow */
 /* eslint-disable sort-keys */
 
-function ReportDispatcher(methods: Array<string>) {
+export default function ReportDispatcher(methods: Array<string>) {
   const dispatchedMethods = methods || [];
 
   for (let i = 0; i < dispatchedMethods.length; i++) {
@@ -73,5 +73,3 @@ function ReportDispatcher(methods: Array<string>) {
     }
   }
 }
-
-module.exports = ReportDispatcher;
diff --git a/packages/jest-jasmine2/src/jasmine/spy_registry.js b/packages/jest-jasmine2/src/jasmine/spy_registry.js
index 5d588079b8d2..355b2a25edb4 100644
--- a/packages/jest-jasmine2/src/jasmine/spy_registry.js
+++ b/packages/jest-jasmine2/src/jasmine/spy_registry.js
@@ -53,7 +53,7 @@ function isSpy(putativeSpy) {
 
 const getErrorMsg = formatErrorMsg('<spyOn>', 'spyOn(<object>, <methodName>)');
 
-function SpyRegistry(options: Object) {
+export default function SpyRegistry(options: Object) {
   options = options || {};
   const currentSpies =
     options.currentSpies ||
@@ -138,5 +138,3 @@ function SpyRegistry(options: Object) {
     }
   };
 }
-
-module.exports = SpyRegistry;
diff --git a/packages/jest-jasmine2/src/jasmine/spy_strategy.js b/packages/jest-jasmine2/src/jasmine/spy_strategy.js
index 10a0b27ca9bf..61394b596152 100644
--- a/packages/jest-jasmine2/src/jasmine/spy_strategy.js
+++ b/packages/jest-jasmine2/src/jasmine/spy_strategy.js
@@ -32,7 +32,7 @@ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 /* @flow */
 /* eslint-disable sort-keys */
 
-function SpyStrategy(options: Object) {
+export default function SpyStrategy(options: Object) {
   options = options || {};
 
   const identity = options.name || 'unknown';
@@ -91,5 +91,3 @@ function SpyStrategy(options: Object) {
     return getSpy();
   };
 }
-
-module.exports = SpyStrategy;
diff --git a/packages/jest-jasmine2/src/jasmine_async.js b/packages/jest-jasmine2/src/jasmine_async.js
index ef78b9cf8773..0618a7cbe9fd 100644
--- a/packages/jest-jasmine2/src/jasmine_async.js
+++ b/packages/jest-jasmine2/src/jasmine_async.js
@@ -107,7 +107,7 @@ function makeConcurrent(originalFn: Function, env) {
   };
 }
 
-function install(global: Global) {
+export function install(global: Global) {
   const jasmine = global.jasmine;
 
   const env = jasmine.getEnv();
@@ -122,7 +122,3 @@ function install(global: Global) {
   env.beforeAll = promisifyLifeCycleFunction(env.beforeAll, env);
   env.beforeEach = promisifyLifeCycleFunction(env.beforeEach, env);
 }
-
-module.exports = {
-  install,
-};
diff --git a/packages/jest-jasmine2/src/jest_expect.js b/packages/jest-jasmine2/src/jest_expect.js
index b9fd2fa48a4c..978ea76c92ce 100644
--- a/packages/jest-jasmine2/src/jest_expect.js
+++ b/packages/jest-jasmine2/src/jest_expect.js
@@ -24,7 +24,7 @@ type JasmineMatcher = {
 };
 type JasmineMatchersObject = {[id: string]: JasmineMatcher};
 
-module.exports = (config: {expand: boolean}) => {
+export default (config: {expand: boolean}) => {
   global.expect = expect;
   expect.setState({expand: config.expand});
   expect.extend({toMatchSnapshot, toThrowErrorMatchingSnapshot});
diff --git a/packages/jest-jasmine2/src/p_timeout.js b/packages/jest-jasmine2/src/p_timeout.js
index fd62fda21df5..0c01120f3d6c 100644
--- a/packages/jest-jasmine2/src/p_timeout.js
+++ b/packages/jest-jasmine2/src/p_timeout.js
@@ -10,7 +10,7 @@
 
 // A specialized version of `p-timeout` that does not touch globals.
 // It does not throw on timeout.
-function pTimeout(
+export default function pTimeout(
   promise: Promise<any>,
   ms: number,
   clearTimeout: (timeoutID: number) => void,
@@ -31,5 +31,3 @@ function pTimeout(
     );
   });
 }
-
-module.exports = pTimeout;
diff --git a/packages/jest-jasmine2/src/queue_runner.js b/packages/jest-jasmine2/src/queue_runner.js
index 148ec7ac673a..22f943135077 100644
--- a/packages/jest-jasmine2/src/queue_runner.js
+++ b/packages/jest-jasmine2/src/queue_runner.js
@@ -25,7 +25,7 @@ type QueueableFn = {
   timeout?: () => number,
 };
 
-function queueRunner(options: Options) {
+export default function queueRunner(options: Options) {
   const token = new PCancelable((onCancel, resolve) => {
     onCancel(resolve);
   });
@@ -82,5 +82,3 @@ function queueRunner(options: Options) {
     then: result.then.bind(result),
   };
 }
-
-module.exports = queueRunner;
diff --git a/packages/jest-jasmine2/src/reporter.js b/packages/jest-jasmine2/src/reporter.js
index 1ac3b94c21fb..cc7ce6b4f7ec 100644
--- a/packages/jest-jasmine2/src/reporter.js
+++ b/packages/jest-jasmine2/src/reporter.js
@@ -35,7 +35,7 @@ type SpecResult = {
 
 type Microseconds = number;
 
-class Jasmine2Reporter {
+export default class Jasmine2Reporter {
   _testResults: Array<AssertionResult>;
   _globalConfig: GlobalConfig;
   _config: ProjectConfig;
@@ -172,5 +172,3 @@ class Jasmine2Reporter {
     return results;
   }
 }
-
-module.exports = Jasmine2Reporter;
diff --git a/packages/jest-jasmine2/src/setup_jest_globals.js b/packages/jest-jasmine2/src/setup_jest_globals.js
index 9b7c31a2c150..a7a040d3c72e 100644
--- a/packages/jest-jasmine2/src/setup_jest_globals.js
+++ b/packages/jest-jasmine2/src/setup_jest_globals.js
@@ -85,7 +85,7 @@ const patchJasmine = () => {
   })(global.jasmine.Spec);
 };
 
-module.exports = ({
+export default ({
   config,
   globalConfig,
   localRequire,
diff --git a/packages/jest-jasmine2/src/tree_processor.js b/packages/jest-jasmine2/src/tree_processor.js
index 93036be6596f..cdbec583e3c6 100644
--- a/packages/jest-jasmine2/src/tree_processor.js
+++ b/packages/jest-jasmine2/src/tree_processor.js
@@ -26,7 +26,7 @@ type TreeNode = {
   children?: Array<TreeNode>,
 };
 
-function treeProcessor(options: Options) {
+export default function treeProcessor(options: Options) {
   const {
     nodeComplete,
     nodeStart,
@@ -76,5 +76,3 @@ function treeProcessor(options: Options) {
     return node.beforeAllFns.concat(children).concat(node.afterAllFns);
   }
 }
-
-module.exports = treeProcessor;
diff --git a/packages/jest-message-util/src/index.js b/packages/jest-message-util/src/index.js
index 32392b1766fe..9f27902cb043 100644
--- a/packages/jest-message-util/src/index.js
+++ b/packages/jest-message-util/src/index.js
@@ -50,7 +50,7 @@ const trimPaths = string =>
 // ExecError is an error thrown outside of the test suite (not inside an `it` or
 // `before/after each` hooks). If it's thrown, none of the tests in the file
 // are executed.
-const formatExecError = (
+export const formatExecError = (
   testResult: TestResult,
   config: StackTraceConfig,
   options: StackTraceOptions,
@@ -148,7 +148,7 @@ const formatPaths = (
   return STACK_TRACE_COLOR(match[1]) + filePath + STACK_TRACE_COLOR(match[3]);
 };
 
-const formatStackTrace = (
+export const formatStackTrace = (
   stack: string,
   config: StackTraceConfig,
   options: StackTraceOptions,
@@ -166,7 +166,7 @@ const formatStackTrace = (
     .join('\n');
 };
 
-const formatResultsErrors = (
+export const formatResultsErrors = (
   testResults: Array<AssertionResult>,
   config: StackTraceConfig,
   options: StackTraceOptions,
@@ -212,7 +212,7 @@ const formatResultsErrors = (
 // jasmine and worker farm sometimes don't give us access to the actual
 // Error object, so we have to regexp out the message from the stack string
 // to format it.
-const separateMessageFromStack = (content: string) => {
+export const separateMessageFromStack = (content: string) => {
   if (!content) {
     return {message: '', stack: ''};
   }
@@ -227,10 +227,3 @@ const separateMessageFromStack = (content: string) => {
   }
   return {message, stack};
 };
-
-module.exports = {
-  formatExecError,
-  formatResultsErrors,
-  formatStackTrace,
-  separateMessageFromStack,
-};
diff --git a/packages/jest-regex-util/src/index.js b/packages/jest-regex-util/src/index.js
index 5a6a0b8828ee..c1f56a8bf210 100644
--- a/packages/jest-regex-util/src/index.js
+++ b/packages/jest-regex-util/src/index.js
@@ -10,7 +10,7 @@
 
 import path from 'path';
 
-const escapePathForRegex = (dir: string) => {
+export const escapePathForRegex = (dir: string) => {
   if (path.sep === '\\') {
     // Replace "\" with "/" so it's not escaped by escapeStrForRegex.
     // replacePathSepForRegex will convert it back.
@@ -19,18 +19,12 @@ const escapePathForRegex = (dir: string) => {
   return replacePathSepForRegex(escapeStrForRegex(dir));
 };
 
-const escapeStrForRegex = (string: string) =>
+export const escapeStrForRegex = (string: string) =>
   string.replace(/[[\]{}()*+?.\\^$|]/g, '\\$&');
 
-const replacePathSepForRegex = (string: string) => {
+export const replacePathSepForRegex = (string: string) => {
   if (path.sep === '\\') {
     return string.replace(/(\/|\\(?!\.))/g, '\\\\');
   }
   return string;
 };
-
-module.exports = {
-  escapePathForRegex,
-  escapeStrForRegex,
-  replacePathSepForRegex,
-};
diff --git a/packages/jest-repl/src/cli/args.js b/packages/jest-repl/src/cli/args.js
index c74e84b8d391..f88f6652f6b4 100644
--- a/packages/jest-repl/src/cli/args.js
+++ b/packages/jest-repl/src/cli/args.js
@@ -10,9 +10,9 @@
 
 import Runtime from 'jest-runtime';
 
-const usage = 'Usage: $0 [--config=<pathToConfigFile>]';
+export const usage = 'Usage: $0 [--config=<pathToConfigFile>]';
 
-const options = Object.assign({}, Runtime.getCLIOptions(), {
+export const options = Object.assign({}, Runtime.getCLIOptions(), {
   replname: {
     alias: 'r',
     description:
@@ -21,8 +21,3 @@ const options = Object.assign({}, Runtime.getCLIOptions(), {
     type: 'string',
   },
 });
-
-module.exports = {
-  options,
-  usage,
-};
diff --git a/packages/jest-repl/src/cli/index.js b/packages/jest-repl/src/cli/index.js
index 7a43faf87029..7695c5944239 100644
--- a/packages/jest-repl/src/cli/index.js
+++ b/packages/jest-repl/src/cli/index.js
@@ -15,7 +15,7 @@ import Runtime from 'jest-runtime';
 import yargs from 'yargs';
 import {validateCLIOptions} from 'jest-util';
 import {version as VERSION} from '../../package.json';
-import args from './args';
+import * as args from './args';
 
 const REPL_SCRIPT = path.resolve(__dirname, './repl.js');
 
diff --git a/packages/jest-resolve/src/default_resolver.js b/packages/jest-resolve/src/default_resolver.js
index 780505ebe924..e72c49370443 100644
--- a/packages/jest-resolve/src/default_resolver.js
+++ b/packages/jest-resolve/src/default_resolver.js
@@ -21,7 +21,10 @@ type ResolverOptions = {|
   rootDir: ?Path,
 |};
 
-function defaultResolver(path: Path, options: ResolverOptions): Path {
+export default function defaultResolver(
+  path: Path,
+  options: ResolverOptions,
+): Path {
   const resolve = options.browser ? browserResolve.sync : resolveSync;
 
   return resolve(path, {
@@ -33,8 +36,6 @@ function defaultResolver(path: Path, options: ResolverOptions): Path {
   });
 }
 
-module.exports = defaultResolver;
-
 /*
  * Adapted from: https://github.com/substack/node-resolve
  */
diff --git a/packages/jest-resolve/src/node_modules_paths.js b/packages/jest-resolve/src/node_modules_paths.js
index a261740961f1..f738c2658cf9 100644
--- a/packages/jest-resolve/src/node_modules_paths.js
+++ b/packages/jest-resolve/src/node_modules_paths.js
@@ -18,7 +18,7 @@ type NodeModulesPathsOptions = {|
   paths?: ?Array<Path>,
 |};
 
-function nodeModulesPaths(
+export default function nodeModulesPaths(
   basedir: Path,
   options: NodeModulesPathsOptions,
 ): Path[] {
@@ -55,5 +55,3 @@ function nodeModulesPaths(
 
   return options.paths ? options.paths.concat(dirs) : dirs;
 }
-
-module.exports = nodeModulesPaths;
diff --git a/packages/jest-runner/src/run_test.js b/packages/jest-runner/src/run_test.js
index 57aedca4f674..a2110f157fa6 100644
--- a/packages/jest-runner/src/run_test.js
+++ b/packages/jest-runner/src/run_test.js
@@ -31,7 +31,7 @@ import docblock from 'jest-docblock';
 // and required implicitly through the `testRunner` ProjectConfig option.
 jasmine2;
 
-function runTest(
+export default function runTest(
   path: Path,
   globalConfig: GlobalConfig,
   config: ProjectConfig,
@@ -136,5 +136,3 @@ function runTest(
         }),
     );
 }
-
-module.exports = runTest;
diff --git a/packages/jest-runner/src/test_worker.js b/packages/jest-runner/src/test_worker.js
index 79baeefad59d..f873f9615ad8 100644
--- a/packages/jest-runner/src/test_worker.js
+++ b/packages/jest-runner/src/test_worker.js
@@ -70,6 +70,7 @@ const getResolver = (config, rawModuleMap) => {
   }
 };
 
+// Cannot be ESM export because of worker-farm
 module.exports = (
   {config, globalConfig, path, rawModuleMap}: WorkerData,
   callback: WorkerCallback,
diff --git a/packages/jest-runtime/src/__tests__/instrumentation.test.js b/packages/jest-runtime/src/__tests__/instrumentation.test.js
index 741a0bca439b..eb5fdd70317a 100644
--- a/packages/jest-runtime/src/__tests__/instrumentation.test.js
+++ b/packages/jest-runtime/src/__tests__/instrumentation.test.js
@@ -9,10 +9,12 @@
 
 'use strict';
 
-jest.mock('vm');
+import vm from 'vm';
+import path from 'path';
+import os from 'os';
+import ScriptTransformer from '../script_transformer';
 
-const path = require('path');
-const os = require('os');
+jest.mock('vm');
 
 const FILE_PATH_TO_INSTRUMENT = path.resolve(
   __dirname,
@@ -20,8 +22,6 @@ const FILE_PATH_TO_INSTRUMENT = path.resolve(
 );
 
 it('instruments files', () => {
-  const vm = require('vm');
-  const ScriptTransformer = require('../script_transformer');
   const config = {
     cache: false,
     cacheDirectory: os.tmpdir(),
diff --git a/packages/jest-runtime/src/__tests__/script_transformer.test.js b/packages/jest-runtime/src/__tests__/script_transformer.test.js
index 54c3ae4ff6ba..42ec311daa12 100644
--- a/packages/jest-runtime/src/__tests__/script_transformer.test.js
+++ b/packages/jest-runtime/src/__tests__/script_transformer.test.js
@@ -164,7 +164,7 @@ describe('ScriptTransformer', () => {
       transformIgnorePatterns: ['/node_modules/'],
     };
 
-    ScriptTransformer = require('../script_transformer');
+    ScriptTransformer = require('../script_transformer').default;
   };
 
   beforeEach(reset);
diff --git a/packages/jest-runtime/src/cli/args.js b/packages/jest-runtime/src/cli/args.js
index 9d0defa5fe1f..a2f2e061e4ca 100644
--- a/packages/jest-runtime/src/cli/args.js
+++ b/packages/jest-runtime/src/cli/args.js
@@ -8,9 +8,9 @@
  * @flow
  */
 
-const usage = 'Usage: $0 [--config=<pathToConfigFile>] <file>';
+export const usage = 'Usage: $0 [--config=<pathToConfigFile>] <file>';
 
-const options = {
+export const options = {
   cache: {
     default: true,
     description:
@@ -40,8 +40,3 @@ const options = {
     type: 'boolean',
   },
 };
-
-module.exports = {
-  options,
-  usage,
-};
diff --git a/packages/jest-runtime/src/cli/index.js b/packages/jest-runtime/src/cli/index.js
index 51704cd08dbf..cf43523b4d3a 100644
--- a/packages/jest-runtime/src/cli/index.js
+++ b/packages/jest-runtime/src/cli/index.js
@@ -17,12 +17,13 @@ import chalk from 'chalk';
 import yargs from 'yargs';
 import {Console, setGlobal, validateCLIOptions} from 'jest-util';
 import {readConfig} from 'jest-config';
+// eslint-disable-next-line import/default
 import Runtime from '../';
-import args from './args';
+import * as args from './args';
 
 const VERSION = (require('../../package.json').version: string);
 
-function run(cliArgv?: Argv, cliInfo?: Array<string>) {
+export function run(cliArgv?: Argv, cliInfo?: Array<string>) {
   let argv;
   if (cliArgv) {
     argv = cliArgv;
@@ -91,5 +92,3 @@ function run(cliArgv?: Argv, cliInfo?: Array<string>) {
       process.on('exit', () => process.exit(1));
     });
 }
-
-exports.run = run;
diff --git a/packages/jest-runtime/src/index.js b/packages/jest-runtime/src/index.js
index 7a77ca39849c..314a9be864d9 100644
--- a/packages/jest-runtime/src/index.js
+++ b/packages/jest-runtime/src/index.js
@@ -26,8 +26,8 @@ import fs from 'graceful-fs';
 import stripBOM from 'strip-bom';
 import ScriptTransformer from './script_transformer';
 import shouldInstrument from './should_instrument';
-import cli from './cli';
-import cliArgs from './cli/args';
+import {run as cilRun} from './cli';
+import {options as cliOptions} from './cli/args';
 
 type Module = {|
   children?: Array<any>,
@@ -264,11 +264,11 @@ class Runtime {
   }
 
   static runCLI(args?: Argv, info?: Array<string>) {
-    return cli.run(args, info);
+    return cilRun(args, info);
   }
 
   static getCLIOptions() {
-    return cliArgs.options;
+    return cliOptions;
   }
 
   requireModule(
diff --git a/packages/jest-runtime/src/script_transformer.js b/packages/jest-runtime/src/script_transformer.js
index e6ed76382d86..9e8aaf79380b 100644
--- a/packages/jest-runtime/src/script_transformer.js
+++ b/packages/jest-runtime/src/script_transformer.js
@@ -46,7 +46,7 @@ const ignoreCache: WeakMap<ProjectConfig, ?RegExp> = new WeakMap();
 // To reset the cache for specific changesets (rather than package version).
 const CACHE_VERSION = '1';
 
-class ScriptTransformer {
+export default class ScriptTransformer {
   static EVAL_RESULT_VARIABLE: string;
   _config: ProjectConfig;
   _transformCache: Map<Path, ?Transformer>;
@@ -474,5 +474,3 @@ const wrap = content =>
   '\n}});';
 
 ScriptTransformer.EVAL_RESULT_VARIABLE = 'Object.<anonymous>';
-
-module.exports = ScriptTransformer;
diff --git a/packages/jest-runtime/src/should_instrument.js b/packages/jest-runtime/src/should_instrument.js
index 1a874e877e77..e1cea4b7ec81 100644
--- a/packages/jest-runtime/src/should_instrument.js
+++ b/packages/jest-runtime/src/should_instrument.js
@@ -19,11 +19,11 @@ const MOCKS_PATTERN = new RegExp(
   escapePathForRegex(path.sep + '__mocks__' + path.sep),
 );
 
-const shouldInstrument = (
+export default function shouldInstrument(
   filename: Path,
   options: Options,
   config: ProjectConfig,
-): boolean => {
+): boolean {
   if (!options.collectCoverage) {
     return false;
   }
@@ -73,6 +73,4 @@ const shouldInstrument = (
   }
 
   return true;
-};
-
-module.exports = shouldInstrument;
+}
diff --git a/packages/jest-snapshot/src/State.js b/packages/jest-snapshot/src/State.js
index 7161a5f8140d..31b1a8007053 100644
--- a/packages/jest-snapshot/src/State.js
+++ b/packages/jest-snapshot/src/State.js
@@ -27,7 +27,7 @@ export type SnapshotStateOptions = {|
   expand?: boolean,
 |};
 
-class SnapshotState {
+export default class SnapshotState {
   _counters: Map<string, number>;
   _dirty: boolean;
   _index: number;
@@ -185,5 +185,3 @@ class SnapshotState {
     }
   }
 }
-
-module.exports = SnapshotState;
diff --git a/packages/jest-snapshot/src/plugins.js b/packages/jest-snapshot/src/plugins.js
index 7c59e75b7e0c..1ecb7f08d0e3 100644
--- a/packages/jest-snapshot/src/plugins.js
+++ b/packages/jest-snapshot/src/plugins.js
@@ -22,8 +22,8 @@ const {
 let PLUGINS = [ReactTestComponent, ReactElement, DOMElement, Immutable];
 
 // Prepend to list so the last added is the first tested.
-exports.addSerializer = (plugin: Plugin) => {
+export const addSerializer = (plugin: Plugin) => {
   PLUGINS = [plugin].concat(PLUGINS);
 };
 
-exports.getSerializers = () => PLUGINS;
+export const getSerializers = () => PLUGINS;
diff --git a/packages/jest-snapshot/src/utils.js b/packages/jest-snapshot/src/utils.js
index d20ec9085284..b7c224d89b80 100644
--- a/packages/jest-snapshot/src/utils.js
+++ b/packages/jest-snapshot/src/utils.js
@@ -18,11 +18,11 @@ import naturalCompare from 'natural-compare';
 import path from 'path';
 import prettyFormat from 'pretty-format';
 
-const SNAPSHOT_EXTENSION = 'snap';
-const SNAPSHOT_VERSION = '1';
+export const SNAPSHOT_EXTENSION = 'snap';
+export const SNAPSHOT_VERSION = '1';
 const SNAPSHOT_VERSION_REGEXP = /^\/\/ Jest Snapshot v(.+),/;
-const SNAPSHOT_GUIDE_LINK = 'https://goo.gl/fbAQLP';
-const SNAPSHOT_VERSION_WARNING = chalk.yellow(
+export const SNAPSHOT_GUIDE_LINK = 'https://goo.gl/fbAQLP';
+export const SNAPSHOT_VERSION_WARNING = chalk.yellow(
   `${chalk.bold('Warning')}: Before you upgrade snapshots, ` +
     `we recommend that you revert any local changes to tests or other code, ` +
     `to ensure that you do not store invalid state.`,
@@ -78,10 +78,10 @@ const validateSnapshotVersion = (snapshotContents: string) => {
   return null;
 };
 
-const testNameToKey = (testName: string, count: number) =>
+export const testNameToKey = (testName: string, count: number) =>
   testName + ' ' + count;
 
-const keyToTestName = (key: string) => {
+export const keyToTestName = (key: string) => {
   if (!/ \d+$/.test(key)) {
     throw new Error('Snapshot keys must end with a number.');
   }
@@ -89,13 +89,16 @@ const keyToTestName = (key: string) => {
   return key.replace(/ \d+$/, '');
 };
 
-const getSnapshotPath = (testPath: Path) =>
+export const getSnapshotPath = (testPath: Path) =>
   path.join(
     path.join(path.dirname(testPath), '__snapshots__'),
     path.basename(testPath) + '.' + SNAPSHOT_EXTENSION,
   );
 
-const getSnapshotData = (snapshotPath: Path, update: SnapshotUpdateState) => {
+export const getSnapshotData = (
+  snapshotPath: Path,
+  update: SnapshotUpdateState,
+) => {
   const data = Object.create(null);
   let snapshotContents = '';
   let dirty = false;
@@ -129,7 +132,7 @@ const getSnapshotData = (snapshotPath: Path, update: SnapshotUpdateState) => {
 const addExtraLineBreaks = string =>
   string.includes('\n') ? `\n${string}\n` : string;
 
-const serialize = (data: any): string => {
+export const serialize = (data: any): string => {
   return addExtraLineBreaks(
     normalizeNewlines(
       prettyFormat(data, {
@@ -142,13 +145,13 @@ const serialize = (data: any): string => {
 };
 
 // unescape double quotes
-const unescape = (data: any): string => data.replace(/\\(")/g, '$1');
+export const unescape = (data: any): string => data.replace(/\\(")/g, '$1');
 
 const printBacktickString = (str: string) => {
   return '`' + str.replace(/`|\\|\${/g, '\\$&') + '`';
 };
 
-const ensureDirectoryExists = (filePath: Path) => {
+export const ensureDirectoryExists = (filePath: Path) => {
   try {
     mkdirp.sync(path.join(path.dirname(filePath)), '777');
   } catch (e) {}
@@ -156,7 +159,7 @@ const ensureDirectoryExists = (filePath: Path) => {
 
 const normalizeNewlines = string => string.replace(/\r\n|\r/g, '\n');
 
-const saveSnapshotFile = (
+export const saveSnapshotFile = (
   snapshotData: {[key: string]: string},
   snapshotPath: Path,
 ) => {
@@ -177,18 +180,3 @@ const saveSnapshotFile = (
     writeSnapshotVersion() + '\n\n' + snapshots.join('\n\n') + '\n',
   );
 };
-
-module.exports = {
-  SNAPSHOT_EXTENSION,
-  SNAPSHOT_GUIDE_LINK,
-  SNAPSHOT_VERSION,
-  SNAPSHOT_VERSION_WARNING,
-  ensureDirectoryExists,
-  getSnapshotData,
-  getSnapshotPath,
-  keyToTestName,
-  saveSnapshotFile,
-  serialize,
-  testNameToKey,
-  unescape,
-};
diff --git a/packages/jest-test-typescript-parser/src/__tests__/type_script_parser.test.js b/packages/jest-test-typescript-parser/src/__tests__/type_script_parser.test.js
index 7999cd43e22b..ff54ebf21138 100644
--- a/packages/jest-test-typescript-parser/src/__tests__/type_script_parser.test.js
+++ b/packages/jest-test-typescript-parser/src/__tests__/type_script_parser.test.js
@@ -8,7 +8,7 @@
 
 'use strict';
 
-const {parse} = require('../type_script_parser');
-const {parserTests} = require('../../../../fixtures/parser_tests');
+import {parse} from '../type_script_parser';
+import {parserTests} from '../../../../fixtures/parser_tests';
 
 parserTests(parse);
diff --git a/packages/jest-test-typescript-parser/src/index.js b/packages/jest-test-typescript-parser/src/index.js
index f8b0e729f237..6b5945cfb61b 100644
--- a/packages/jest-test-typescript-parser/src/index.js
+++ b/packages/jest-test-typescript-parser/src/index.js
@@ -9,7 +9,7 @@
  */
 
 import {parse as babylonParser, ItBlock, Expect} from 'jest-editor-support';
-import TypeScriptParser from './type_script_parser';
+import * as TypeScriptParser from './type_script_parser';
 
 export type ParserReturn = {
   itBlocks: Array<ItBlock>,
diff --git a/packages/jest-test-typescript-parser/src/type_script_parser.js b/packages/jest-test-typescript-parser/src/type_script_parser.js
index 49602576626a..f00112b59f78 100644
--- a/packages/jest-test-typescript-parser/src/type_script_parser.js
+++ b/packages/jest-test-typescript-parser/src/type_script_parser.js
@@ -13,7 +13,7 @@ import {readFileSync} from 'fs';
 import ts from 'typescript';
 import {Expect, ItBlock, Node} from 'jest-editor-support';
 
-function parse(file: string) {
+export function parse(file: string) {
   const sourceFile = ts.createSourceFile(
     file,
     readFileSync(file).toString(),
@@ -83,7 +83,3 @@ function getNode<T: Node>(
   node.file = file.fileName;
   return node;
 }
-
-module.exports = {
-  parse,
-};
diff --git a/packages/jest-util/src/Console.js b/packages/jest-util/src/Console.js
index c1e729d8e1e1..b63b7ba643b0 100644
--- a/packages/jest-util/src/Console.js
+++ b/packages/jest-util/src/Console.js
@@ -17,7 +17,7 @@ import clearLine from './clear_line';
 
 type Formatter = (type: LogType, message: LogMessage) => string;
 
-class CustomConsole extends Console {
+export default class CustomConsole extends Console {
   _stdout: stream$Writable;
   _formatBuffer: Formatter;
 
@@ -55,5 +55,3 @@ class CustomConsole extends Console {
     return null;
   }
 }
-
-module.exports = CustomConsole;
diff --git a/packages/jest-util/src/__tests__/fake_timers.test.js b/packages/jest-util/src/__tests__/fake_timers.test.js
index 9cf8439fe5c3..dec5f604a962 100644
--- a/packages/jest-util/src/__tests__/fake_timers.test.js
+++ b/packages/jest-util/src/__tests__/fake_timers.test.js
@@ -15,7 +15,7 @@ describe('FakeTimers', () => {
   let FakeTimers, moduleMocker;
 
   beforeEach(() => {
-    FakeTimers = require('../fake_timers');
+    FakeTimers = require('../fake_timers').default;
     const mock = require('jest-mock');
     const global = vm.runInNewContext('this');
     moduleMocker = new mock.ModuleMocker(global);
diff --git a/packages/jest-util/src/__tests__/format_test_results.test.js b/packages/jest-util/src/__tests__/format_test_results.test.js
index f5ae7ddd250c..7ff7e89c7cff 100644
--- a/packages/jest-util/src/__tests__/format_test_results.test.js
+++ b/packages/jest-util/src/__tests__/format_test_results.test.js
@@ -9,7 +9,7 @@
 
 'use strict';
 
-const formatTestResults = require('../format_test_results');
+import formatTestResults from '../format_test_results';
 
 describe('formatTestResults', () => {
   const assertion = {
diff --git a/packages/jest-util/src/__tests__/validate_cli_options.test.js b/packages/jest-util/src/__tests__/validate_cli_options.test.js
index a36e01318d49..114bdf8f1427 100644
--- a/packages/jest-util/src/__tests__/validate_cli_options.test.js
+++ b/packages/jest-util/src/__tests__/validate_cli_options.test.js
@@ -9,7 +9,7 @@
 
 'use strict';
 
-const validateCLIOptions = require('../validate_cli_options');
+import validateCLIOptions from '../validate_cli_options';
 
 test('validates yargs special options', () => {
   const options = ['$0', '_', 'help', 'h'];
diff --git a/packages/jest-util/src/buffered_console.js b/packages/jest-util/src/buffered_console.js
index cc601f724cc6..77e24f621dc8 100644
--- a/packages/jest-util/src/buffered_console.js
+++ b/packages/jest-util/src/buffered_console.js
@@ -14,7 +14,7 @@ import {Console} from 'console';
 import {format} from 'util';
 import callsites from 'callsites';
 
-class BufferedConsole extends Console {
+export default class BufferedConsole extends Console {
   _buffer: ConsoleBuffer;
 
   constructor() {
@@ -55,5 +55,3 @@ class BufferedConsole extends Console {
     return this._buffer;
   }
 }
-
-module.exports = BufferedConsole;
diff --git a/packages/jest-util/src/clear_line.js b/packages/jest-util/src/clear_line.js
index 48776f3cead1..8386fbbc41d7 100644
--- a/packages/jest-util/src/clear_line.js
+++ b/packages/jest-util/src/clear_line.js
@@ -9,7 +9,7 @@
  */
 /* global stream$Writable */
 
-module.exports = (stream: stream$Writable | tty$WriteStream) => {
+export default (stream: stream$Writable | tty$WriteStream) => {
   if (process.stdout.isTTY) {
     stream.write('\x1b[999D\x1b[K');
   }
diff --git a/packages/jest-util/src/fake_timers.js b/packages/jest-util/src/fake_timers.js
index 001a66455cf2..a4423281b533 100644
--- a/packages/jest-util/src/fake_timers.js
+++ b/packages/jest-util/src/fake_timers.js
@@ -60,7 +60,7 @@ type TimerAPI = {
 
 const MS_IN_A_YEAR = 31536000000;
 
-class FakeTimers {
+export default class FakeTimers {
   _cancelledImmediates: {[key: TimerID]: boolean};
   _cancelledTicks: {[key: TimerID]: boolean};
   _config: ProjectConfig;
@@ -532,5 +532,3 @@ class FakeTimers {
     }
   }
 }
-
-module.exports = FakeTimers;
diff --git a/packages/jest-util/src/format_test_results.js b/packages/jest-util/src/format_test_results.js
index 8c844fe4bb2f..a940ee38f96e 100644
--- a/packages/jest-util/src/format_test_results.js
+++ b/packages/jest-util/src/format_test_results.js
@@ -72,7 +72,7 @@ function formatTestAssertion(
   return result;
 }
 
-function formatTestResults(
+export default function formatTestResults(
   results: AggregatedResult,
   codeCoverageFormatter?: CodeCoverageFormatter,
   reporter?: CodeCoverageReporter,
@@ -87,5 +87,3 @@ function formatTestResults(
     testResults,
   });
 }
-
-module.exports = formatTestResults;
diff --git a/packages/jest-util/src/get_console_output.js b/packages/jest-util/src/get_console_output.js
index 13c59b8ff29c..eb60b96443ba 100644
--- a/packages/jest-util/src/get_console_output.js
+++ b/packages/jest-util/src/get_console_output.js
@@ -13,7 +13,7 @@ import type {ConsoleBuffer} from 'types/Console';
 import path from 'path';
 import chalk from 'chalk';
 
-module.exports = (root: string, verbose: boolean, buffer: ConsoleBuffer) => {
+export default (root: string, verbose: boolean, buffer: ConsoleBuffer) => {
   const TITLE_INDENT = verbose ? '  ' : '    ';
   const CONSOLE_INDENT = TITLE_INDENT + '  ';
 
diff --git a/packages/jest-util/src/install_common_globals.js b/packages/jest-util/src/install_common_globals.js
index 60ce7e14af03..bcc9023cc733 100644
--- a/packages/jest-util/src/install_common_globals.js
+++ b/packages/jest-util/src/install_common_globals.js
@@ -24,7 +24,7 @@ function deepCopy(obj) {
   return newObj;
 }
 
-module.exports = (global: Global, globals: ConfigGlobals) => {
+export default (global: Global, globals: ConfigGlobals) => {
   // Forward some APIs
   global.Buffer = Buffer;
 
diff --git a/packages/jest-util/src/null_console.js b/packages/jest-util/src/null_console.js
index c54d2f5ec5b8..3eb108bb60e5 100644
--- a/packages/jest-util/src/null_console.js
+++ b/packages/jest-util/src/null_console.js
@@ -10,7 +10,7 @@
 
 import Console from './Console';
 
-class NullConsole extends Console {
+export default class NullConsole extends Console {
   assert() {}
   dir() {}
   error() {}
@@ -21,5 +21,3 @@ class NullConsole extends Console {
   trace() {}
   warn() {}
 }
-
-module.exports = NullConsole;
diff --git a/packages/jest-util/src/set_global.js b/packages/jest-util/src/set_global.js
index a8270880c7a5..d9a70dd7955e 100644
--- a/packages/jest-util/src/set_global.js
+++ b/packages/jest-util/src/set_global.js
@@ -10,5 +10,5 @@
 
 import type {Global} from 'types/Global';
 
-module.exports = (global: Global, key: string, value: any) =>
+export default (global: Global, key: string, value: any) =>
   (global[key] = value);
diff --git a/packages/jest-util/src/validate_cli_options.js b/packages/jest-util/src/validate_cli_options.js
index 9e54f458a8b5..ae6e67f2fcdf 100644
--- a/packages/jest-util/src/validate_cli_options.js
+++ b/packages/jest-util/src/validate_cli_options.js
@@ -44,7 +44,7 @@ const createCLIValidationError = (
   return new ValidationError(title, message, comment);
 };
 
-const validateCLIOptions = (argv: Argv, options: Object) => {
+export default function validateCLIOptions(argv: Argv, options: Object) {
   const yargsSpecialOptions = ['$0', '_', 'help', 'h'];
   const allowedOptions = Object.keys(options).reduce(
     (acc, option) => acc.add(option).add(options[option].alias || option),
@@ -59,6 +59,4 @@ const validateCLIOptions = (argv: Argv, options: Object) => {
   }
 
   return true;
-};
-
-module.exports = validateCLIOptions;
+}
diff --git a/packages/jest-validate/src/__tests__/validate.test.js b/packages/jest-validate/src/__tests__/validate.test.js
index da71c398384e..7c63f0d7ea77 100644
--- a/packages/jest-validate/src/__tests__/validate.test.js
+++ b/packages/jest-validate/src/__tests__/validate.test.js
@@ -9,9 +9,10 @@
 
 'use strict';
 
-const validate = require('../validate');
-const jestValidateExampleConfig = require('../example_config');
-const jestValidateDefaultConfig = require('../default_config');
+import validate from '../validate';
+import jestValidateExampleConfig from '../example_config';
+import jestValidateDefaultConfig from '../default_config';
+
 const {
   defaultConfig,
   validConfig,
diff --git a/packages/jest-validate/src/condition.js b/packages/jest-validate/src/condition.js
index ddb28abf007e..07cf673ef034 100644
--- a/packages/jest-validate/src/condition.js
+++ b/packages/jest-validate/src/condition.js
@@ -10,12 +10,13 @@
 
 const toString = Object.prototype.toString;
 
-const validationCondition = (option: any, validOption: any): boolean => {
+export default function validationCondition(
+  option: any,
+  validOption: any,
+): boolean {
   return (
     option === null ||
     option === undefined ||
     toString.call(option) === toString.call(validOption)
   );
-};
-
-module.exports = validationCondition;
+}
diff --git a/packages/jest-validate/src/default_config.js b/packages/jest-validate/src/default_config.js
index 32f16ac13dfe..cf9f630fb0c0 100644
--- a/packages/jest-validate/src/default_config.js
+++ b/packages/jest-validate/src/default_config.js
@@ -17,7 +17,7 @@ import exampleConfig from './example_config';
 import validationCondition from './condition';
 import {ERROR, DEPRECATION, WARNING} from './utils';
 
-module.exports = ({
+export default ({
   comment: '',
   condition: validationCondition,
   deprecate: deprecationWarning,
diff --git a/packages/jest-validate/src/deprecated.js b/packages/jest-validate/src/deprecated.js
index 22f42c1e0dad..a257de1f50f6 100644
--- a/packages/jest-validate/src/deprecated.js
+++ b/packages/jest-validate/src/deprecated.js
@@ -19,7 +19,7 @@ const deprecationMessage = (message: string, options: ValidationOptions) => {
   logValidationWarning(name, message, comment);
 };
 
-const deprecationWarning = (
+export const deprecationWarning = (
   config: Object,
   option: string,
   deprecatedOptions: Object,
@@ -33,7 +33,3 @@ const deprecationWarning = (
 
   return false;
 };
-
-module.exports = {
-  deprecationWarning,
-};
diff --git a/packages/jest-validate/src/errors.js b/packages/jest-validate/src/errors.js
index fe34f56167b1..c108cbe9016f 100644
--- a/packages/jest-validate/src/errors.js
+++ b/packages/jest-validate/src/errors.js
@@ -14,7 +14,7 @@ import chalk from 'chalk';
 import getType from 'jest-get-type';
 import {format, ValidationError, ERROR} from './utils';
 
-const errorMessage = (
+export const errorMessage = (
   option: string,
   received: any,
   defaultValue: any,
@@ -35,8 +35,3 @@ const errorMessage = (
 
   throw new ValidationError(name, message, comment);
 };
-
-module.exports = {
-  ValidationError,
-  errorMessage,
-};
diff --git a/packages/jest-validate/src/example_config.js b/packages/jest-validate/src/example_config.js
index 0bfb256156d1..75b65d947a52 100644
--- a/packages/jest-validate/src/example_config.js
+++ b/packages/jest-validate/src/example_config.js
@@ -27,4 +27,4 @@ const config: ValidationOptions = {
   unknown: (config, option, options) => {},
 };
 
-module.exports = config;
+export default config;
diff --git a/packages/jest-validate/src/index.js b/packages/jest-validate/src/index.js
index d4d5eeb0c04d..9ba3dbcbc2a0 100644
--- a/packages/jest-validate/src/index.js
+++ b/packages/jest-validate/src/index.js
@@ -8,8 +8,12 @@
  * @flow
  */
 
-import {createDidYouMeanMessage, format, logValidationWarning} from './utils';
-import {ValidationError} from './errors';
+import {
+  createDidYouMeanMessage,
+  format,
+  logValidationWarning,
+  ValidationError,
+} from './utils';
 import validate from './validate';
 
 module.exports = {
diff --git a/packages/jest-validate/src/utils.js b/packages/jest-validate/src/utils.js
index 28cf24cae481..2449decf4642 100644
--- a/packages/jest-validate/src/utils.js
+++ b/packages/jest-validate/src/utils.js
@@ -13,16 +13,16 @@ import prettyFormat from 'pretty-format';
 import leven from 'leven';
 
 const BULLET: string = chalk.bold('\u25cf');
-const DEPRECATION = `${BULLET} Deprecation Warning`;
-const ERROR = `${BULLET} Validation Error`;
-const WARNING = `${BULLET} Validation Warning`;
+export const DEPRECATION = `${BULLET} Deprecation Warning`;
+export const ERROR = `${BULLET} Validation Error`;
+export const WARNING = `${BULLET} Validation Warning`;
 
-const format = (value: any): string =>
+export const format = (value: any): string =>
   typeof value === 'function'
     ? value.toString()
     : prettyFormat(value, {min: true});
 
-class ValidationError extends Error {
+export class ValidationError extends Error {
   name: string;
   message: string;
 
@@ -35,7 +35,7 @@ class ValidationError extends Error {
   }
 }
 
-const logValidationWarning = (
+export const logValidationWarning = (
   name: string,
   message: string,
   comment?: ?string,
@@ -44,7 +44,7 @@ const logValidationWarning = (
   console.warn(chalk.yellow(chalk.bold(name) + ':\n\n' + message + comment));
 };
 
-const createDidYouMeanMessage = (
+export const createDidYouMeanMessage = (
   unrecognized: string,
   allowedOptions: Array<string>,
 ) => {
@@ -55,13 +55,3 @@ const createDidYouMeanMessage = (
 
   return suggestion ? `Did you mean ${chalk.bold(format(suggestion))}?` : '';
 };
-
-module.exports = {
-  DEPRECATION,
-  ERROR,
-  ValidationError,
-  WARNING,
-  createDidYouMeanMessage,
-  format,
-  logValidationWarning,
-};
diff --git a/packages/jest-validate/src/validate.js b/packages/jest-validate/src/validate.js
index c079ebf94c99..6083642d9176 100644
--- a/packages/jest-validate/src/validate.js
+++ b/packages/jest-validate/src/validate.js
@@ -64,4 +64,4 @@ const validate = (config: Object, options: ValidationOptions) => {
   };
 };
 
-module.exports = validate;
+export default validate;
diff --git a/packages/jest-validate/src/warnings.js b/packages/jest-validate/src/warnings.js
index f54b9cf419fc..c6031f15e713 100644
--- a/packages/jest-validate/src/warnings.js
+++ b/packages/jest-validate/src/warnings.js
@@ -18,7 +18,7 @@ import {
   WARNING,
 } from './utils';
 
-const unknownOptionWarning = (
+export const unknownOptionWarning = (
   config: Object,
   exampleConfig: Object,
   option: string,
@@ -40,7 +40,3 @@ const unknownOptionWarning = (
 
   logValidationWarning(name, message, comment);
 };
-
-module.exports = {
-  unknownOptionWarning,
-};
diff --git a/packages/pretty-format/src/__tests__/expect_util.js b/packages/pretty-format/src/__tests__/expect_util.js
index f99f06ea4b6d..baedb3648cf6 100644
--- a/packages/pretty-format/src/__tests__/expect_util.js
+++ b/packages/pretty-format/src/__tests__/expect_util.js
@@ -15,43 +15,41 @@ import type {OptionsReceived, Plugins} from 'types/PrettyFormat';
 const diff = require('jest-diff');
 const prettyFormat = require('../');
 
-module.exports = {
-  getPrettyPrint: (plugins: Plugins) =>
-    function(received: any, expected: any, options?: OptionsReceived) {
-      const prettyFormatted = prettyFormat(
-        received,
-        Object.assign(
-          ({
-            plugins,
-          }: OptionsReceived),
-          options,
-        ),
-      );
-      const pass = prettyFormatted === expected;
+export const getPrettyPrint = (plugins: Plugins) =>
+  function(received: any, expected: any, options?: OptionsReceived) {
+    const prettyFormatted = prettyFormat(
+      received,
+      Object.assign(
+        ({
+          plugins,
+        }: OptionsReceived),
+        options,
+      ),
+    );
+    const pass = prettyFormatted === expected;
 
-      const message = pass
-        ? () =>
-            this.utils.matcherHint('.not.toBe') +
+    const message = pass
+      ? () =>
+          this.utils.matcherHint('.not.toBe') +
+          '\n\n' +
+          `Expected value to not be:\n` +
+          `  ${this.utils.printExpected(expected)}\n` +
+          `Received:\n` +
+          `  ${this.utils.printReceived(prettyFormatted)}`
+      : () => {
+          const diffString = diff(expected, prettyFormatted, {
+            expand: this.expand,
+          });
+          return (
+            this.utils.matcherHint('.toBe') +
             '\n\n' +
-            `Expected value to not be:\n` +
+            `Expected value to be:\n` +
             `  ${this.utils.printExpected(expected)}\n` +
             `Received:\n` +
-            `  ${this.utils.printReceived(prettyFormatted)}`
-        : () => {
-            const diffString = diff(expected, prettyFormatted, {
-              expand: this.expand,
-            });
-            return (
-              this.utils.matcherHint('.toBe') +
-              '\n\n' +
-              `Expected value to be:\n` +
-              `  ${this.utils.printExpected(expected)}\n` +
-              `Received:\n` +
-              `  ${this.utils.printReceived(prettyFormatted)}` +
-              (diffString ? `\n\nDifference:\n\n${diffString}` : '')
-            );
-          };
+            `  ${this.utils.printReceived(prettyFormatted)}` +
+            (diffString ? `\n\nDifference:\n\n${diffString}` : '')
+          );
+        };
 
-      return {actual: prettyFormatted, message, pass};
-    },
-};
+    return {actual: prettyFormatted, message, pass};
+  };
diff --git a/packages/pretty-format/src/__tests__/immutable.test.js b/packages/pretty-format/src/__tests__/immutable.test.js
index 0fe67f621d3e..9e72fc923f8a 100644
--- a/packages/pretty-format/src/__tests__/immutable.test.js
+++ b/packages/pretty-format/src/__tests__/immutable.test.js
@@ -12,14 +12,12 @@
 
 import React from 'react';
 import Immutable from 'immutable';
-import prettyFormat from '../';
-const {Immutable: ImmutablePlugin, ReactElement} = prettyFormat.plugins;
-import expectUtil from './expect_util';
-
-const toPrettyPrintTo = expectUtil.getPrettyPrint([
-  ReactElement,
-  ImmutablePlugin,
-]);
+import {getPrettyPrint} from './expect_util';
+
+const {plugins: prettyPlugins} = require('../');
+const {Immutable: ImmutablePlugin, ReactElement} = prettyPlugins;
+
+const toPrettyPrintTo = getPrettyPrint([ReactElement, ImmutablePlugin]);
 
 const expect = global.expect;
 expect.extend({toPrettyPrintTo});