diff --git a/CHANGELOG.md b/CHANGELOG.md
index 04fa2befe1f9..15c5cedd2e56 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -56,6 +56,7 @@
 - `[jest-snapshot]` Omit irrelevant `received` properties when property matchers fail ([#9198](https://github.com/facebook/jest/pull/9198))
 - `[jest-transform]` Properly cache transformed files across tests ([#8890](https://github.com/facebook/jest/pull/8890))
 - `[jest-transform]` Don't fail the test suite when a generated source map is invalid ([#9058](https://github.com/facebook/jest/pull/9058))
+- `[jest-types]` [**BREAKING**] Use less `null | undefined` in config types ([#9200](https://github.com/facebook/jest/pull/9200))
 - `[jest-utils]` Allow querying process.domain ([#9136](https://github.com/facebook/jest/pull/9136))
 - `[pretty-format]` Correctly detect memoized elements ([#9196](https://github.com/facebook/jest/pull/9196))
 
diff --git a/e2e/__tests__/__snapshots__/moduleNameMapper.test.ts.snap b/e2e/__tests__/__snapshots__/moduleNameMapper.test.ts.snap
index ca8e5b11d543..73bf63d59f7a 100644
--- a/e2e/__tests__/__snapshots__/moduleNameMapper.test.ts.snap
+++ b/e2e/__tests__/__snapshots__/moduleNameMapper.test.ts.snap
@@ -19,7 +19,7 @@ FAIL __tests__/index.js
       "moduleNameMapper": {
         "/\\.(css|less)$/": "no-such-module"
       },
-      "resolver": null
+      "resolver": undefined
     }
 
        8 | 'use strict';
diff --git a/e2e/__tests__/__snapshots__/showConfig.test.ts.snap b/e2e/__tests__/__snapshots__/showConfig.test.ts.snap
index 6e77a0ed28f2..d0ad02f0098e 100644
--- a/e2e/__tests__/__snapshots__/showConfig.test.ts.snap
+++ b/e2e/__tests__/__snapshots__/showConfig.test.ts.snap
@@ -13,14 +13,11 @@ exports[`--showConfig outputs config info and exits 1`] = `
         "/node_modules/"
       ],
       "cwd": "<<REPLACED_ROOT_DIR>>",
-      "dependencyExtractor": null,
       "detectLeaks": false,
       "detectOpenHandles": false,
       "errorOnDeprecated": false,
-      "filter": null,
+      "extraGlobals": [],
       "forceCoverageMatch": [],
-      "globalSetup": null,
-      "globalTeardown": null,
       "globals": {},
       "haste": {
         "computeSha1": false,
@@ -38,13 +35,12 @@ exports[`--showConfig outputs config info and exits 1`] = `
         "tsx",
         "node"
       ],
-      "moduleNameMapper": {},
+      "moduleNameMapper": [],
       "modulePathIgnorePatterns": [],
       "name": "[md5 hash]",
       "prettierPath": "prettier",
       "resetMocks": false,
       "resetModules": false,
-      "resolver": null,
       "restoreMocks": false,
       "rootDir": "<<REPLACED_ROOT_DIR>>",
       "roots": [
@@ -72,7 +68,8 @@ exports[`--showConfig outputs config info and exits 1`] = `
       "transform": [
         [
           "^.+\\\\.[jt]sx?$",
-          "<<REPLACED_JEST_PACKAGES_DIR>>/babel-jest/build/index.js"
+          "<<REPLACED_JEST_PACKAGES_DIR>>/babel-jest/build/index.js",
+          {}
         ]
       ],
       "transformIgnorePatterns": [
@@ -93,35 +90,37 @@ exports[`--showConfig outputs config info and exits 1`] = `
       "lcov",
       "clover"
     ],
-    "coverageThreshold": null,
     "detectLeaks": false,
     "detectOpenHandles": false,
     "errorOnDeprecated": false,
     "expand": false,
-    "filter": null,
-    "globalSetup": null,
-    "globalTeardown": null,
+    "extraGlobals": [],
+    "findRelatedTests": false,
+    "forceExit": false,
     "json": false,
+    "lastCommit": false,
     "listTests": false,
+    "logHeapUsage": false,
     "maxConcurrency": 5,
     "maxWorkers": "[maxWorkers]",
     "noStackTrace": false,
     "nonFlagArgs": [],
     "notify": false,
     "notifyMode": "failure-change",
+    "onlyChanged": false,
+    "onlyFailures": false,
     "passWithNoTests": false,
-    "projects": null,
+    "projects": [],
     "rootDir": "<<REPLACED_ROOT_DIR>>",
     "runTestsByPath": false,
     "skipFilter": false,
     "testFailureExitCode": 1,
     "testPathPattern": "",
-    "testResultsProcessor": null,
     "testSequencer": "<<REPLACED_JEST_PACKAGES_DIR>>/jest-test-sequencer/build/index.js",
     "updateSnapshot": "all",
     "useStderr": false,
-    "verbose": null,
     "watch": false,
+    "watchAll": false,
     "watchman": true
   },
   "version": "[version]"
diff --git a/packages/jest-cli/src/init/__tests__/__snapshots__/init.test.js.snap b/packages/jest-cli/src/init/__tests__/__snapshots__/init.test.js.snap
index 768ccc23e640..63b08ad015bb 100644
--- a/packages/jest-cli/src/init/__tests__/__snapshots__/init.test.js.snap
+++ b/packages/jest-cli/src/init/__tests__/__snapshots__/init.test.js.snap
@@ -42,10 +42,10 @@ module.exports = {
   // collectCoverage: false,
 
   // An array of glob patterns indicating a set of files for which coverage information should be collected
-  // collectCoverageFrom: null,
+  // collectCoverageFrom: undefined,
 
   // The directory where Jest should output its coverage files
-  // coverageDirectory: null,
+  // coverageDirectory: undefined,
 
   // An array of regexp pattern strings used to skip coverage collection
   // coveragePathIgnorePatterns: [
@@ -61,10 +61,10 @@ module.exports = {
   // ],
 
   // An object that configures minimum threshold enforcement for coverage results
-  // coverageThreshold: null,
+  // coverageThreshold: undefined,
 
   // A path to a custom dependency extractor
-  // dependencyExtractor: null,
+  // dependencyExtractor: undefined,
 
   // Make calling deprecated APIs throw helpful error messages
   // errorOnDeprecated: false,
@@ -73,10 +73,10 @@ module.exports = {
   // forceCoverageMatch: [],
 
   // A path to a module which exports an async function that is triggered once before all test suites
-  // globalSetup: null,
+  // globalSetup: undefined,
 
   // A path to a module which exports an async function that is triggered once after all test suites
-  // globalTeardown: null,
+  // globalTeardown: undefined,
 
   // A set of global variables that need to be available in all test environments
   // globals: {},
@@ -112,10 +112,10 @@ module.exports = {
   // notifyMode: \\"failure-change\\",
 
   // A preset that is used as a base for Jest's configuration
-  // preset: null,
+  // preset: undefined,
 
   // Run tests from one or more projects
-  // projects: null,
+  // projects: undefined,
 
   // Use this configuration option to add custom reporters to Jest
   // reporters: undefined,
@@ -127,13 +127,13 @@ module.exports = {
   // resetModules: false,
 
   // A path to a custom resolver
-  // resolver: null,
+  // resolver: undefined,
 
   // Automatically restore mock state between every test
   // restoreMocks: false,
 
   // The root directory that Jest should scan for tests and modules within
-  // rootDir: null,
+  // rootDir: undefined,
 
   // A list of paths to directories that Jest should use to search for files in
   // roots: [
@@ -176,7 +176,7 @@ module.exports = {
   // testRegex: [],
 
   // This option allows the use of a custom results processor
-  // testResultsProcessor: null,
+  // testResultsProcessor: undefined,
 
   // This option allows use of a custom test runner
   // testRunner: \\"jasmine2\\",
@@ -188,7 +188,7 @@ module.exports = {
   // timers: \\"real\\",
 
   // A map from regular expressions to paths to transformers
-  // transform: null,
+  // transform: undefined,
 
   // An array of regexp pattern strings that are matched against all source file paths, matched files will skip transformation
   // transformIgnorePatterns: [
@@ -199,7 +199,7 @@ module.exports = {
   // unmockedModulePathPatterns: undefined,
 
   // Indicates whether each individual test should be reported during the run
-  // verbose: null,
+  // verbose: undefined,
 
   // An array of regexp patterns that are matched against all source file paths before re-running tests in watch mode
   // watchPathIgnorePatterns: [],
diff --git a/packages/jest-config/src/Defaults.ts b/packages/jest-config/src/Defaults.ts
index 26c40f2f912f..e096029b7795 100644
--- a/packages/jest-config/src/Defaults.ts
+++ b/packages/jest-config/src/Defaults.ts
@@ -21,18 +21,11 @@ const defaultOptions: Config.DefaultOptions = {
   changedFilesWithAncestor: false,
   clearMocks: false,
   collectCoverage: false,
-  collectCoverageFrom: null,
-  coverageDirectory: null,
   coveragePathIgnorePatterns: [NODE_MODULES_REGEXP],
   coverageReporters: ['json', 'text', 'lcov', 'clover'],
-  coverageThreshold: null,
-  dependencyExtractor: null,
   errorOnDeprecated: false,
   expand: false,
-  filter: null,
   forceCoverageMatch: [],
-  globalSetup: null,
-  globalTeardown: null,
   globals: {},
   haste: {
     computeSha1: false,
@@ -48,14 +41,10 @@ const defaultOptions: Config.DefaultOptions = {
   noStackTrace: false,
   notify: false,
   notifyMode: 'failure-change',
-  preset: null,
   prettierPath: 'prettier',
-  projects: null,
   resetMocks: false,
   resetModules: false,
-  resolver: null,
   restoreMocks: false,
-  rootDir: null,
   roots: ['<rootDir>'],
   runTestsByPath: false,
   runner: 'jest-runner',
@@ -70,15 +59,12 @@ const defaultOptions: Config.DefaultOptions = {
   testMatch: ['**/__tests__/**/*.[jt]s?(x)', '**/?(*.)+(spec|test).[tj]s?(x)'],
   testPathIgnorePatterns: [NODE_MODULES_REGEXP],
   testRegex: [],
-  testResultsProcessor: null,
   testRunner: 'jasmine2',
   testSequencer: '@jest/test-sequencer',
   testURL: 'http://localhost',
   timers: 'real',
-  transform: null,
   transformIgnorePatterns: [NODE_MODULES_REGEXP],
   useStderr: false,
-  verbose: null,
   watch: false,
   watchPathIgnorePatterns: [],
   watchman: true,
diff --git a/packages/jest-config/src/__tests__/normalize.test.js b/packages/jest-config/src/__tests__/normalize.test.js
index 6820fc169e20..8bf1a94417de 100644
--- a/packages/jest-config/src/__tests__/normalize.test.js
+++ b/packages/jest-config/src/__tests__/normalize.test.js
@@ -328,12 +328,12 @@ describe('transform', () => {
     );
 
     expect(options.transform).toEqual([
-      [DEFAULT_CSS_PATTERN, '/root/node_modules/jest-regex-util'],
-      [DEFAULT_JS_PATTERN, require.resolve('babel-jest')],
-      ['abs-path', '/qux/quux'],
+      [DEFAULT_CSS_PATTERN, '/root/node_modules/jest-regex-util', {}],
+      [DEFAULT_JS_PATTERN, require.resolve('babel-jest'), {}],
+      ['abs-path', '/qux/quux', {}],
     ]);
   });
-  it("pulls in config if it's passed as an array", () => {
+  it("pulls in config if it's passed as an array, and defaults to empty object", () => {
     const {options} = normalize(
       {
         rootDir: '/root/',
@@ -346,9 +346,9 @@ describe('transform', () => {
       {},
     );
     expect(options.transform).toEqual([
-      [DEFAULT_CSS_PATTERN, '/root/node_modules/jest-regex-util'],
+      [DEFAULT_CSS_PATTERN, '/root/node_modules/jest-regex-util', {}],
       [DEFAULT_JS_PATTERN, require.resolve('babel-jest'), {rootMode: 'upward'}],
-      ['abs-path', '/qux/quux'],
+      ['abs-path', '/qux/quux', {}],
     ]);
   });
 });
@@ -822,7 +822,7 @@ describe('Upgrade help', () => {
       {},
     );
 
-    expect(options.transform).toEqual([['.*', '/node_modules/bar/baz']]);
+    expect(options.transform).toEqual([['.*', '/node_modules/bar/baz', {}]]);
     expect(options.transformIgnorePatterns).toEqual([
       joinForPattern('bar', 'baz'),
       joinForPattern('qux', 'quux'),
@@ -1152,8 +1152,8 @@ describe('preset', () => {
       '/node_modules/b',
     ]);
     expect(options.transform).toEqual([
-      ['a', '/node_modules/a'],
-      ['b', '/node_modules/b'],
+      ['a', '/node_modules/a', {}],
+      ['b', '/node_modules/b', {}],
     ]);
   });
 
@@ -1202,10 +1202,10 @@ describe('preset', () => {
     );
 
     expect(options.transform).toEqual([
-      ['e', '/node_modules/ee'],
-      ['b', '/node_modules/bb'],
-      ['c', '/node_modules/cc'],
-      ['a', '/node_modules/aa'],
+      ['e', '/node_modules/ee', {}],
+      ['b', '/node_modules/bb', {}],
+      ['c', '/node_modules/cc', {}],
+      ['a', '/node_modules/aa', {}],
     ]);
   });
 
diff --git a/packages/jest-config/src/normalize.ts b/packages/jest-config/src/normalize.ts
index 100b4338cc06..96111241f9d3 100644
--- a/packages/jest-config/src/normalize.ts
+++ b/packages/jest-config/src/normalize.ts
@@ -673,7 +673,7 @@ export default function normalize(
                 key,
                 rootDir: options.rootDir,
               }),
-              ...(Array.isArray(transformElement) ? [transformElement[1]] : []),
+              Array.isArray(transformElement) ? transformElement[1] : {},
             ];
           });
         break;
@@ -947,6 +947,29 @@ export default function normalize(
     newOptions.onlyChanged = newOptions.watch;
   }
 
+  if (!newOptions.onlyChanged) {
+    newOptions.onlyChanged = false;
+  }
+
+  if (!newOptions.lastCommit) {
+    newOptions.lastCommit = false;
+  }
+
+  if (!newOptions.onlyFailures) {
+    newOptions.onlyFailures = false;
+  }
+
+  if (!newOptions.watchAll) {
+    newOptions.watchAll = false;
+  }
+
+  // as any since it can happen. We really need to fix the types here
+  if (
+    newOptions.moduleNameMapper === (DEFAULT_CONFIG.moduleNameMapper as any)
+  ) {
+    newOptions.moduleNameMapper = [];
+  }
+
   newOptions.updateSnapshot =
     argv.ci && !argv.updateSnapshot
       ? 'none'
@@ -1014,6 +1037,26 @@ export default function normalize(
     newOptions.collectCoverageFrom = [];
   }
 
+  if (!newOptions.findRelatedTests) {
+    newOptions.findRelatedTests = false;
+  }
+
+  if (!newOptions.projects) {
+    newOptions.projects = [];
+  }
+
+  if (!newOptions.extraGlobals) {
+    newOptions.extraGlobals = [];
+  }
+
+  if (!newOptions.forceExit) {
+    newOptions.forceExit = false;
+  }
+
+  if (!newOptions.logHeapUsage) {
+    newOptions.logHeapUsage = false;
+  }
+
   return {
     hasDeprecationWarnings,
     options: newOptions,
diff --git a/packages/jest-haste-map/src/index.ts b/packages/jest-haste-map/src/index.ts
index 61b83f7ea904..b936e149bf55 100644
--- a/packages/jest-haste-map/src/index.ts
+++ b/packages/jest-haste-map/src/index.ts
@@ -54,7 +54,7 @@ type Options = {
   computeDependencies?: boolean;
   computeSha1?: boolean;
   console?: Console;
-  dependencyExtractor?: string;
+  dependencyExtractor?: string | null;
   extensions: Array<string>;
   forceNodeFilesystemAPI?: boolean;
   hasteImplModulePath?: string;
@@ -79,7 +79,7 @@ type InternalOptions = {
   cacheDirectory: string;
   computeDependencies: boolean;
   computeSha1: boolean;
-  dependencyExtractor?: string;
+  dependencyExtractor: string | null;
   extensions: Array<string>;
   forceNodeFilesystemAPI: boolean;
   hasteImplModulePath?: string;
@@ -251,7 +251,7 @@ class HasteMap extends EventEmitter {
           ? true
           : options.computeDependencies,
       computeSha1: options.computeSha1 || false,
-      dependencyExtractor: options.dependencyExtractor,
+      dependencyExtractor: options.dependencyExtractor || null,
       extensions: options.extensions,
       forceNodeFilesystemAPI: !!options.forceNodeFilesystemAPI,
       hasteImplModulePath: options.hasteImplModulePath,
diff --git a/packages/jest-haste-map/src/types.ts b/packages/jest-haste-map/src/types.ts
index 075df3f167b2..aa1b4ee5e24e 100644
--- a/packages/jest-haste-map/src/types.ts
+++ b/packages/jest-haste-map/src/types.ts
@@ -16,7 +16,7 @@ export type Mapper = (item: string) => Array<string> | null;
 export type WorkerMessage = {
   computeDependencies: boolean;
   computeSha1: boolean;
-  dependencyExtractor?: string;
+  dependencyExtractor?: string | null;
   rootDir: string;
   filePath: string;
   hasteImplModulePath?: string;
diff --git a/packages/jest-reporters/src/coverage_reporter.ts b/packages/jest-reporters/src/coverage_reporter.ts
index 505b04f04e41..dde9ed0a6b5d 100644
--- a/packages/jest-reporters/src/coverage_reporter.ts
+++ b/packages/jest-reporters/src/coverage_reporter.ts
@@ -107,7 +107,7 @@ export default class CoverageReporter extends BaseReporter {
       );
     }
 
-    this._checkThreshold(this._globalConfig, map);
+    this._checkThreshold(map);
   }
 
   private async _addUntestedFiles(
@@ -209,11 +209,10 @@ export default class CoverageReporter extends BaseReporter {
     }
   }
 
-  private _checkThreshold(
-    globalConfig: Config.GlobalConfig,
-    map: istanbulCoverage.CoverageMap,
-  ) {
-    if (globalConfig.coverageThreshold) {
+  private _checkThreshold(map: istanbulCoverage.CoverageMap) {
+    const {coverageThreshold} = this._globalConfig;
+
+    if (coverageThreshold) {
       function check(
         name: string,
         thresholds: Config.CoverageThresholdValue,
@@ -250,7 +249,7 @@ export default class CoverageReporter extends BaseReporter {
         PATH: 'path',
       };
       const coveredFiles = map.files();
-      const thresholdGroups = Object.keys(globalConfig.coverageThreshold);
+      const thresholdGroups = Object.keys(coverageThreshold);
       const groupTypeByThresholdGroup: {[index: string]: string} = {};
       const filesByGlob: {[index: string]: Array<string>} = {};
 
@@ -342,7 +341,7 @@ export default class CoverageReporter extends BaseReporter {
               errors = errors.concat(
                 check(
                   thresholdGroup,
-                  globalConfig.coverageThreshold[thresholdGroup],
+                  coverageThreshold[thresholdGroup],
                   coverage,
                 ),
               );
@@ -357,7 +356,7 @@ export default class CoverageReporter extends BaseReporter {
               errors = errors.concat(
                 check(
                   thresholdGroup,
-                  globalConfig.coverageThreshold[thresholdGroup],
+                  coverageThreshold[thresholdGroup],
                   coverage,
                 ),
               );
@@ -370,7 +369,7 @@ export default class CoverageReporter extends BaseReporter {
                 errors = errors.concat(
                   check(
                     fileMatchingGlob,
-                    globalConfig.coverageThreshold[thresholdGroup],
+                    coverageThreshold[thresholdGroup],
                     map.fileCoverageFor(fileMatchingGlob).toSummary(),
                   ),
                 );
diff --git a/packages/jest-resolve/src/types.ts b/packages/jest-resolve/src/types.ts
index 1c65ac50af57..03b372b0cfd5 100644
--- a/packages/jest-resolve/src/types.ts
+++ b/packages/jest-resolve/src/types.ts
@@ -14,7 +14,7 @@ export type ResolverConfig = {
   hasCoreModules: boolean;
   moduleDirectories: Array<string>;
   moduleNameMapper?: Array<ModuleNameMapperConfig> | null;
-  modulePaths: Array<Config.Path>;
+  modulePaths?: Array<Config.Path>;
   platforms?: Array<string>;
   resolver?: Config.Path | null;
   rootDir: Config.Path;
diff --git a/packages/jest-runtime/src/cli/index.ts b/packages/jest-runtime/src/cli/index.ts
index 0c701d5a29f1..a70cf4ac3ead 100644
--- a/packages/jest-runtime/src/cli/index.ts
+++ b/packages/jest-runtime/src/cli/index.ts
@@ -68,10 +68,9 @@ export function run(cliArgv?: Config.Argv, cliInfo?: Array<string>) {
   const options = readConfig(argv, root);
   const globalConfig = options.globalConfig;
   // Always disable automocking in scripts.
-  const config = {
+  const config: Config.ProjectConfig = {
     ...options.projectConfig,
     automock: false,
-    unmockedModulePathPatterns: null,
   };
 
   // Break circular dependency
diff --git a/packages/jest-runtime/src/index.ts b/packages/jest-runtime/src/index.ts
index e56d5c3ca113..e6de0ba3d73e 100644
--- a/packages/jest-runtime/src/index.ts
+++ b/packages/jest-runtime/src/index.ts
@@ -123,7 +123,7 @@ class Runtime {
       changedFiles: undefined,
       collectCoverage: false,
       collectCoverageFrom: [],
-      collectCoverageOnlyFrom: null,
+      collectCoverageOnlyFrom: undefined,
     };
     this._currentlyExecutingModulePath = '';
     this._environment = environment;
@@ -489,7 +489,7 @@ class Runtime {
       collectCoverage: this._coverageOptions.collectCoverage,
       collectCoverageFrom: this._coverageOptions.collectCoverageFrom,
       collectCoverageOnlyFrom: this._coverageOptions.collectCoverageOnlyFrom,
-      extraGlobals: this._config.extraGlobals || [],
+      extraGlobals: this._config.extraGlobals,
     };
   }
 
@@ -713,7 +713,6 @@ class Runtime {
     Object.defineProperty(localModule, 'require', {
       value: this._createRequireImplementation(localModule, options),
     });
-    const extraGlobals = this._config.extraGlobals || [];
     const transformedFile = this._scriptTransformer.transform(
       filename,
       this._getFullTransformationOptions(options),
@@ -750,7 +749,7 @@ class Runtime {
         filename,
         localModule.require as LocalModuleRequire,
       ), // jest object
-      ...extraGlobals.map(globalVariable => {
+      ...this._config.extraGlobals.map(globalVariable => {
         if (this._environment.global[globalVariable]) {
           return this._environment.global[globalVariable];
         }
diff --git a/packages/jest-transform/src/ScriptTransformer.ts b/packages/jest-transform/src/ScriptTransformer.ts
index e8a971aa2905..20a73eca63a2 100644
--- a/packages/jest-transform/src/ScriptTransformer.ts
+++ b/packages/jest-transform/src/ScriptTransformer.ts
@@ -347,6 +347,7 @@ export default class ScriptTransformer {
   ): TransformResult {
     const isInternalModule = !!(options && options.isInternalModule);
     const isCoreModule = !!(options && options.isCoreModule);
+    const extraGlobals = (options && options.extraGlobals) || [];
     const content = stripShebang(
       fileSource || fs.readFileSync(filename, 'utf8'),
     );
@@ -361,8 +362,6 @@ export default class ScriptTransformer {
       (this.shouldTransform(filename) || instrument);
 
     try {
-      const extraGlobals = (options && options.extraGlobals) || [];
-
       if (willTransform) {
         const transformedSource = this.transformSource(
           filename,
diff --git a/packages/jest-transform/src/types.ts b/packages/jest-transform/src/types.ts
index 541d2b225074..a0b980f26caf 100644
--- a/packages/jest-transform/src/types.ts
+++ b/packages/jest-transform/src/types.ts
@@ -17,7 +17,7 @@ export type ShouldInstrumentOptions = Pick<
 };
 
 export type Options = ShouldInstrumentOptions &
-  Pick<Config.GlobalConfig, 'extraGlobals'> & {
+  Partial<Pick<Config.GlobalConfig, 'extraGlobals'>> & {
     isCoreModule?: boolean;
     isInternalModule?: boolean;
   };
diff --git a/packages/jest-types/src/Config.ts b/packages/jest-types/src/Config.ts
index 3cb344ce9932..f498f8f843a3 100644
--- a/packages/jest-types/src/Config.ts
+++ b/packages/jest-types/src/Config.ts
@@ -15,7 +15,7 @@ export type Glob = string;
 
 export type HasteConfig = {
   computeSha1?: boolean;
-  defaultPlatform?: string | null | undefined;
+  defaultPlatform?: string | null;
   hasteImplModulePath?: string;
   platforms?: Array<string>;
   providesModuleNodeModules: Array<string>;
@@ -36,49 +36,29 @@ export type DefaultOptions = {
   changedFilesWithAncestor: boolean;
   clearMocks: boolean;
   collectCoverage: boolean;
-  collectCoverageFrom: Array<string> | null | undefined;
-  coverageDirectory: string | null | undefined;
   coveragePathIgnorePatterns: Array<string>;
   coverageReporters: Array<string>;
-  coverageThreshold:
-    | {
-        global: {
-          [key: string]: number;
-        };
-      }
-    | null
-    | undefined;
-  dependencyExtractor: string | null | undefined;
   errorOnDeprecated: boolean;
   expand: boolean;
-  filter: Path | null | undefined;
   forceCoverageMatch: Array<Glob>;
   globals: ConfigGlobals;
-  globalSetup: string | null | undefined;
-  globalTeardown: string | null | undefined;
   haste: HasteConfig;
-  maxWorkers: number | string;
   maxConcurrency: number;
+  maxWorkers: number | string;
   moduleDirectories: Array<string>;
   moduleFileExtensions: Array<string>;
-  moduleNameMapper: {
-    [key: string]: string;
-  };
+  moduleNameMapper: Record<string, string>;
   modulePathIgnorePatterns: Array<string>;
   noStackTrace: boolean;
   notify: boolean;
-  notifyMode: string;
-  preset: string | null | undefined;
-  prettierPath: string | null | undefined;
-  projects: Array<string | ProjectConfig> | null | undefined;
+  notifyMode: NotifyMode;
+  prettierPath: string;
   resetMocks: boolean;
   resetModules: boolean;
-  resolver: Path | null | undefined;
   restoreMocks: boolean;
-  rootDir: Path | null | undefined;
-  roots: Array<Path> | null | undefined;
-  runner: string;
+  roots: Array<Path>;
   runTestsByPath: boolean;
+  runner: 'jest-runner';
   setupFiles: Array<Path>;
   setupFilesAfterEnv: Array<Path>;
   skipFilter: boolean;
@@ -90,22 +70,14 @@ export type DefaultOptions = {
   testMatch: Array<Glob>;
   testPathIgnorePatterns: Array<string>;
   testRegex: Array<string>;
-  testResultsProcessor: string | null | undefined;
-  testRunner: string | null | undefined;
+  testRunner: string;
   testSequencer: string;
   testURL: string;
   timers: 'real' | 'fake';
-  transform:
-    | {
-        [regex: string]: Path | TransformerConfig;
-      }
-    | null
-    | undefined;
   transformIgnorePatterns: Array<Glob>;
-  watchPathIgnorePatterns: Array<string>;
   useStderr: boolean;
-  verbose: boolean | null | undefined;
   watch: boolean;
+  watchPathIgnorePatterns: Array<string>;
   watchman: boolean;
 };
 
@@ -210,7 +182,7 @@ export type InitialOptions = Partial<{
   testPathDirs: Array<Path>;
   testPathIgnorePatterns: Array<string>;
   testRegex: string | Array<string>;
-  testResultsProcessor: string | null | undefined;
+  testResultsProcessor: string;
   testRunner: string;
   testSequencer: string;
   testURL: string;
@@ -224,7 +196,7 @@ export type InitialOptions = Partial<{
   unmockedModulePathPatterns: Array<string>;
   updateSnapshot: boolean;
   useStderr: boolean;
-  verbose: boolean | null | undefined;
+  verbose?: boolean;
   watch: boolean;
   watchAll: boolean;
   watchman: boolean;
@@ -255,38 +227,32 @@ type CoverageThreshold = {
 
 export type GlobalConfig = {
   bail: number;
-  changedSince: string;
+  changedSince?: string;
   changedFilesWithAncestor: boolean;
   collectCoverage: boolean;
   collectCoverageFrom: Array<Glob>;
-  collectCoverageOnlyFrom:
-    | {
-        [key: string]: boolean;
-      }
-    | null
-    | undefined;
+  collectCoverageOnlyFrom?: {
+    [key: string]: boolean;
+  };
   coverageDirectory: string;
   coveragePathIgnorePatterns?: Array<string>;
   coverageReporters: Array<keyof ReportOptions>;
-  coverageThreshold: CoverageThreshold;
+  coverageThreshold?: CoverageThreshold;
   detectLeaks: boolean;
   detectOpenHandles: boolean;
-  enabledTestsMap:
-    | {
-        [key: string]: {
-          [key: string]: boolean;
-        };
-      }
-    | null
-    | undefined;
+  enabledTestsMap?: {
+    [key: string]: {
+      [key: string]: boolean;
+    };
+  };
   expand: boolean;
   extraGlobals: Array<string>;
-  filter: Path | null | undefined;
+  filter?: Path;
   findRelatedTests: boolean;
   forceExit: boolean;
   json: boolean;
-  globalSetup: string | null | undefined;
-  globalTeardown: string | null | undefined;
+  globalSetup?: string;
+  globalTeardown?: string;
   lastCommit: boolean;
   logHeapUsage: boolean;
   listTests: boolean;
@@ -294,40 +260,37 @@ export type GlobalConfig = {
   maxWorkers: number;
   noStackTrace: boolean;
   nonFlagArgs: Array<string>;
-  noSCM: boolean | null | undefined;
+  noSCM?: boolean;
   notify: boolean;
   notifyMode: NotifyMode;
-  outputFile: Path | null | undefined;
+  outputFile?: Path;
   onlyChanged: boolean;
   onlyFailures: boolean;
   passWithNoTests: boolean;
   projects: Array<Glob>;
-  replname: string | null | undefined;
-  reporters: Array<string | ReporterConfig>;
+  replname?: string;
+  reporters?: Array<string | ReporterConfig>;
   runTestsByPath: boolean;
   rootDir: Path;
-  silent: boolean;
+  silent?: boolean;
   skipFilter: boolean;
   errorOnDeprecated: boolean;
   testFailureExitCode: number;
-  testNamePattern: string;
+  testNamePattern?: string;
   testPathPattern: string;
-  testResultsProcessor: string | null | undefined;
+  testResultsProcessor?: string;
   testSequencer: string;
-  testTimeout: number;
+  testTimeout?: number;
   updateSnapshot: SnapshotUpdateState;
   useStderr: boolean;
-  verbose: boolean | null | undefined;
+  verbose?: boolean;
   watch: boolean;
   watchAll: boolean;
   watchman: boolean;
-  watchPlugins:
-    | Array<{
-        path: string;
-        config: Record<string, any>;
-      }>
-    | null
-    | undefined;
+  watchPlugins?: Array<{
+    path: string;
+    config: Record<string, any>;
+  }> | null;
 };
 
 export type ProjectConfig = {
@@ -344,23 +307,23 @@ export type ProjectConfig = {
   displayName?: DisplayName;
   errorOnDeprecated: boolean;
   extraGlobals: Array<keyof NodeJS.Global>;
-  filter: Path | null | undefined;
+  filter?: Path;
   forceCoverageMatch: Array<Glob>;
-  globalSetup: string | null | undefined;
-  globalTeardown: string | null | undefined;
+  globalSetup?: string;
+  globalTeardown?: string;
   globals: ConfigGlobals;
   haste: HasteConfig;
   moduleDirectories: Array<string>;
   moduleFileExtensions: Array<string>;
-  moduleLoader: Path;
+  moduleLoader?: Path;
   moduleNameMapper: Array<[string, string]>;
   modulePathIgnorePatterns: Array<string>;
-  modulePaths: Array<string>;
+  modulePaths?: Array<string>;
   name: string;
   prettierPath: string;
   resetMocks: boolean;
   resetModules: boolean;
-  resolver: Path | null | undefined;
+  resolver?: Path;
   restoreMocks: boolean;
   rootDir: Path;
   roots: Array<Path>;
@@ -368,8 +331,8 @@ export type ProjectConfig = {
   setupFiles: Array<Path>;
   setupFilesAfterEnv: Array<Path>;
   skipFilter: boolean;
-  skipNodeResolution: boolean;
-  snapshotResolver: Path | null | undefined;
+  skipNodeResolution?: boolean;
+  snapshotResolver?: Path;
   snapshotSerializers: Array<Path>;
   testEnvironment: string;
   testEnvironmentOptions: Record<string, any>;
@@ -383,7 +346,7 @@ export type ProjectConfig = {
   transform: Array<[string, Path, Record<string, unknown>]>;
   transformIgnorePatterns: Array<Glob>;
   watchPathIgnorePatterns: Array<string>;
-  unmockedModulePathPatterns: Array<string> | null | undefined;
+  unmockedModulePathPatterns?: Array<string>;
 };
 
 export type Argv = Arguments<
@@ -456,7 +419,7 @@ export type Argv = Arguments<
     testPathIgnorePatterns: Array<string>;
     testPathPattern: Array<string>;
     testRegex: string | Array<string>;
-    testResultsProcessor: string | null | undefined;
+    testResultsProcessor: string;
     testRunner: string;
     testSequencer: string;
     testURL: string;
@@ -467,7 +430,7 @@ export type Argv = Arguments<
     unmockedModulePathPatterns: Array<string> | null | undefined;
     updateSnapshot: boolean;
     useStderr: boolean;
-    verbose: boolean | null | undefined;
+    verbose: boolean;
     version: boolean;
     watch: boolean;
     watchAll: boolean;