diff --git a/@commitlint/cli/cli.js b/@commitlint/cli/cli.js
old mode 100644
new mode 100755
diff --git a/@commitlint/cli/src/cli.ts b/@commitlint/cli/src/cli.ts
index 18a2eb7545..1d761f1d06 100644
--- a/@commitlint/cli/src/cli.ts
+++ b/@commitlint/cli/src/cli.ts
@@ -13,7 +13,8 @@ import {
 	LintOutcome,
 	ParserOptions,
 	ParserPreset,
-	QualifiedConfig
+	QualifiedConfig,
+	Formatter
 } from '@commitlint/types';
 import {CliError} from './cli-error';
 
@@ -177,7 +178,7 @@ async function main(options: CliFlags) {
 
 	const results = await Promise.all(
 		// TODO: validate why those types do not match
-		messages.map(message => lint(message, loaded.rules as any, opts))
+		messages.map(message => lint(message, loaded.rules, opts))
 	);
 
 	if (Object.keys(loaded.rules).length === 0) {
@@ -338,10 +339,8 @@ function selectParserOpts(parserPreset: ParserPreset) {
 	return parserPreset.parserOpts;
 }
 
-function loadFormatter(config: QualifiedConfig, flags: CliFlags) {
-	// TODO: validate why formatter is unknown????
-	const moduleName: string =
-		flags.format || (config.formatter as any) || '@commitlint/format';
+function loadFormatter(config: QualifiedConfig, flags: CliFlags): Formatter {
+	const moduleName = flags.format || config.formatter || '@commitlint/format';
 	const modulePath =
 		resolveFrom.silent(__dirname, moduleName) ||
 		resolveFrom.silent(flags.cwd, moduleName) ||
diff --git a/@commitlint/format/package.json b/@commitlint/format/package.json
index d8d8201f69..ceb59d27f5 100644
--- a/@commitlint/format/package.json
+++ b/@commitlint/format/package.json
@@ -37,6 +37,7 @@
     "@commitlint/utils": "^8.3.4"
   },
   "dependencies": {
+    "@commitlint/types": "^8.3.5",
     "chalk": "^3.0.0"
   }
 }
diff --git a/@commitlint/format/src/format.ts b/@commitlint/format/src/format.ts
index 050c8fba63..cf75cf824d 100644
--- a/@commitlint/format/src/format.ts
+++ b/@commitlint/format/src/format.ts
@@ -1,41 +1,19 @@
 import chalk from 'chalk';
+import {
+	ChalkColor,
+	FormattableReport,
+	FormatOptions,
+	FormattableResult,
+	WithInput
+} from '@commitlint/types';
 
 const DEFAULT_SIGNS = [' ', '⚠', '✖'] as const;
 const DEFAULT_COLORS = ['white', 'yellow', 'red'] as const;
 
-export interface FormattableProblem {
-	level: 0 | 1 | 2;
-	name: string;
-	message: string;
-}
-
-export interface FormattableResult {
-	errors?: FormattableProblem[];
-	warnings?: FormattableProblem[];
-}
-
-export interface WithInput {
-	input?: string;
-}
-
-export interface FormattableReport {
-	results?: (FormattableResult & WithInput)[];
-}
-
-export type ChalkColor = keyof typeof chalk;
-
-export interface FormatOptions {
-	color?: boolean;
-	signs?: readonly [string, string, string];
-	colors?: readonly [ChalkColor, ChalkColor, ChalkColor];
-	verbose?: boolean;
-	helpUrl?: string;
-}
-
 export function format(
 	report: FormattableReport = {},
 	options: FormatOptions = {}
-) {
+): string {
 	const {results = []} = report;
 	const fi = (result: FormattableResult & WithInput) =>
 		formatInput(result, options);
diff --git a/@commitlint/format/tsconfig.json b/@commitlint/format/tsconfig.json
index 49479bf34f..119e645565 100644
--- a/@commitlint/format/tsconfig.json
+++ b/@commitlint/format/tsconfig.json
@@ -6,5 +6,6 @@
     "outDir": "./lib"
   },
   "include": ["./src"],
-  "exclude": ["./src/**/*.test.ts", "./lib/**/*"]
+  "exclude": ["./src/**/*.test.ts", "./lib/**/*"],
+  "references": [{"path": "../types"}]
 }
diff --git a/@commitlint/lint/src/lint.test.ts b/@commitlint/lint/src/lint.test.ts
index c8ff6cc123..521f826b4a 100644
--- a/@commitlint/lint/src/lint.test.ts
+++ b/@commitlint/lint/src/lint.test.ts
@@ -125,8 +125,8 @@ test('throws for rule with invalid level', async () => {
 
 test('throws for rule with out of range level', async () => {
 	const error = lint('type(scope): foo', {
-		'type-enum': [-1, 'always'],
-		'header-max-length': [3, 'always']
+		'type-enum': [-1, 'always'] as any,
+		'header-max-length': [3, 'always'] as any
 	});
 
 	await expect(error).rejects.toThrow('rule type-enum must be between 0 and 2');
diff --git a/@commitlint/lint/src/lint.ts b/@commitlint/lint/src/lint.ts
index 3807afe73e..8df8cd77a2 100644
--- a/@commitlint/lint/src/lint.ts
+++ b/@commitlint/lint/src/lint.ts
@@ -4,17 +4,17 @@ import parse from '@commitlint/parse';
 import defaultRules from '@commitlint/rules';
 import {buildCommitMesage} from './commit-message';
 import {
-	LintRuleConfig,
 	LintOptions,
 	LintOutcome,
 	LintRuleOutcome,
 	Rule,
-	RuleSeverity
+	RuleConfigSeverity,
+	QualifiedRules
 } from '@commitlint/types';
 
 export default async function lint(
 	message: string,
-	rawRulesConfig?: LintRuleConfig,
+	rawRulesConfig?: QualifiedRules,
 	rawOpts?: LintOptions
 ): Promise<LintOutcome> {
 	const opts = rawOpts
@@ -76,7 +76,7 @@ export default async function lint(
 
 			const [level] = config;
 
-			if (level === RuleSeverity.Disabled && config.length === 1) {
+			if (level === RuleConfigSeverity.Disabled && config.length === 1) {
 				return null;
 			}
 
@@ -132,10 +132,10 @@ export default async function lint(
 
 	// Validate against all rules
 	const results = Object.entries(rulesConfig)
-		.filter(([, [level]]) => level > 0)
+		.filter(([, config]) => typeof config !== 'undefined' && config[0] > 0)
 		.map(entry => {
 			const [name, config] = entry;
-			const [level, when, value] = config;
+			const [level, when, value] = config!; //
 
 			// Level 0 rules are ignored
 			if (level === 0) {
@@ -148,8 +148,7 @@ export default async function lint(
 				throw new Error(`Could not find rule implementation for ${name}`);
 			}
 
-			const executableRule = rule as Rule<unknown>;
-			const [valid, message] = executableRule(parsed, when, value);
+			const [valid, message] = rule(parsed, when, value as any);
 
 			return {
 				level,
diff --git a/@commitlint/types/src/format.ts b/@commitlint/types/src/format.ts
new file mode 100644
index 0000000000..ba50d8a79f
--- /dev/null
+++ b/@commitlint/types/src/format.ts
@@ -0,0 +1,37 @@
+import chalk from 'chalk';
+import {QualifiedRules} from './load';
+import {RuleConfigSeverity} from './rules';
+
+export type Formatter = (
+	report: FormattableReport,
+	options: FormatOptions
+) => string;
+
+export interface FormattableProblem {
+	level: RuleConfigSeverity;
+	name: keyof QualifiedRules;
+	message: string;
+}
+
+export interface FormattableResult {
+	errors?: FormattableProblem[];
+	warnings?: FormattableProblem[];
+}
+
+export interface WithInput {
+	input?: string;
+}
+
+export interface FormattableReport {
+	results?: (FormattableResult & WithInput)[];
+}
+
+export type ChalkColor = keyof typeof chalk;
+
+export interface FormatOptions {
+	color?: boolean;
+	signs?: readonly [string, string, string];
+	colors?: readonly [ChalkColor, ChalkColor, ChalkColor];
+	verbose?: boolean;
+	helpUrl?: string;
+}
diff --git a/@commitlint/types/src/index.ts b/@commitlint/types/src/index.ts
index f562854fed..562a9a6373 100644
--- a/@commitlint/types/src/index.ts
+++ b/@commitlint/types/src/index.ts
@@ -1,4 +1,5 @@
 export * from './ensure';
+export * from './format';
 export * from './is-ignored';
 export * from './rules';
 export * from './lint';
diff --git a/@commitlint/types/src/lint.ts b/@commitlint/types/src/lint.ts
index 6ebf81e448..e9f047e9e0 100644
--- a/@commitlint/types/src/lint.ts
+++ b/@commitlint/types/src/lint.ts
@@ -1,10 +1,11 @@
 import {IsIgnoredOptions} from './is-ignored';
-import {RuleConfigTuple, PluginRecords, RuleSeverity} from './load';
+import {PluginRecords} from './load';
 import {ParserOptions} from './parse';
+import {RuleConfigSeverity, RuleConfigTuple} from './rules';
 
 export type LintRuleConfig = Record<
 	string,
-	| Readonly<[RuleSeverity.Disabled]>
+	| Readonly<[RuleConfigSeverity.Disabled]>
 	| RuleConfigTuple<void>
 	| RuleConfigTuple<unknown>
 >;
@@ -35,7 +36,7 @@ export interface LintRuleOutcome {
 	/** If the commit is considered valid for the rule */
 	valid: boolean;
 	/** The "severity" of the rule (1 = warning, 2 = error) */
-	level: RuleSeverity;
+	level: RuleConfigSeverity;
 	/** The name of the rule */
 	name: string;
 	/** The message returned from the rule, if invalid */
diff --git a/@commitlint/types/src/load.ts b/@commitlint/types/src/load.ts
index 7779136556..25c05d7aff 100644
--- a/@commitlint/types/src/load.ts
+++ b/@commitlint/types/src/load.ts
@@ -1,5 +1,4 @@
-import {TargetCaseType} from './ensure';
-import {Rule, RuleCondition} from './rules';
+import {Rule, RulesConfig, RuleConfigQuality} from './rules';
 
 export type PluginRecords = Record<string, Plugin>;
 
@@ -14,84 +13,9 @@ export interface LoadOptions {
 	file?: string;
 }
 
-export enum RuleSeverity {
-	Disabled = 0,
-	Warning = 1,
-	Error = 2
-}
-
-export type RuleConfigTuple<T> = T extends void
-	? Readonly<[RuleSeverity, RuleCondition]>
-	: Readonly<[RuleSeverity, RuleCondition, T]>;
-
-export enum RuleConfigQuality {
-	User,
-	Qualified
-}
-
-export type QualifiedRuleConfig<T> =
-	| (() => RuleConfigTuple<T>)
-	| (() => RuleConfigTuple<Promise<T>>)
-	| RuleConfigTuple<T>;
-
-export type RuleConfig<
-	V = RuleConfigQuality.Qualified,
-	T = void
-> = V extends RuleConfigQuality.Qualified
-	? RuleConfigTuple<T>
-	: QualifiedRuleConfig<T>;
-
-export type CaseRuleConfig<V = RuleConfigQuality.User> = RuleConfig<
-	V,
-	TargetCaseType
->;
-export type LengthRuleConfig<V = RuleConfigQuality.User> = RuleConfig<
-	V,
-	number
->;
-export type EnumRuleConfig<V = RuleConfigQuality.User> = RuleConfig<
-	V,
-	string[]
->;
-
-export type RulesConfig<V = RuleConfigQuality.User> = {
-	'body-case': CaseRuleConfig<V>;
-	'body-empty': RuleConfig<V>;
-	'body-leading-blank': RuleConfig<V>;
-	'body-max-length': LengthRuleConfig<V>;
-	'body-max-line-length': LengthRuleConfig<V>;
-	'body-min-length': LengthRuleConfig<V>;
-	'footer-empty': RuleConfig<V>;
-	'footer-leading-blank': RuleConfig<V>;
-	'footer-max-length': LengthRuleConfig<V>;
-	'footer-max-line-length': LengthRuleConfig<V>;
-	'footer-min-length': LengthRuleConfig<V>;
-	'header-case': CaseRuleConfig<V>;
-	'header-full-stop': RuleConfig<V>;
-	'header-max-length': LengthRuleConfig<V>;
-	'header-min-length': LengthRuleConfig<V>;
-	'references-empty': RuleConfig<V>;
-	'scope-case': CaseRuleConfig<V>;
-	'scope-empty': RuleConfig<V>;
-	'scope-enum': EnumRuleConfig<V>;
-	'scope-max-length': LengthRuleConfig<V>;
-	'scope-min-length': LengthRuleConfig<V>;
-	'signed-off-by': RuleConfig<V>;
-	'subject-case': CaseRuleConfig<V>;
-	'subject-empty': RuleConfig<V>;
-	'subject-full-stop': RuleConfig<V>;
-	'subject-max-length': LengthRuleConfig<V>;
-	'subject-min-length': LengthRuleConfig<V>;
-	'type-case': CaseRuleConfig<V>;
-	'type-empty': RuleConfig<V>;
-	'type-enum': EnumRuleConfig<V>;
-	'type-max-length': LengthRuleConfig<V>;
-	'type-min-length': LengthRuleConfig<V>;
-};
-
 export interface UserConfig {
 	extends?: string[];
-	formatter?: unknown;
+	formatter?: string;
 	rules?: Partial<RulesConfig>;
 	parserPreset?: string | ParserPreset;
 	ignores?: ((commit: string) => boolean)[];
@@ -101,7 +25,7 @@ export interface UserConfig {
 
 export interface UserPreset {
 	extends?: string[];
-	formatter?: unknown;
+	formatter?: string;
 	rules?: Partial<RulesConfig>;
 	parserPreset?: string | ParserPreset;
 	ignores?: ((commit: string) => boolean)[];
@@ -113,7 +37,7 @@ export type QualifiedRules = Partial<RulesConfig<RuleConfigQuality.Qualified>>;
 
 export interface QualifiedConfig {
 	extends: string[];
-	formatter: unknown;
+	formatter: string;
 	rules: QualifiedRules;
 	parserPreset: ParserPreset;
 	ignores: ((commit: string) => boolean)[];
diff --git a/@commitlint/types/src/rules.ts b/@commitlint/types/src/rules.ts
index b064cb4d32..73d0c62d2f 100644
--- a/@commitlint/types/src/rules.ts
+++ b/@commitlint/types/src/rules.ts
@@ -1,12 +1,6 @@
+import {TargetCaseType} from './ensure';
 import {Commit} from './parse';
 
-/**
- * Rules always have a condition.
- * It can be either "always" (as tested), or "never" (as tested).
- * For example, `header-full-stop` can be enforced as "always" or "never".
- */
-export type RuleCondition = 'always' | 'never';
-
 /**
  * Rules match the input either as successful or failed.
  * For example, when `header-full-stop` detects a full stop and is set as "always"; it's true.
@@ -20,6 +14,103 @@ export type RuleOutcome = [boolean, string?];
  */
 export type Rule<Value = never> = (
 	parsed: Commit,
-	when?: RuleCondition,
+	when?: RuleConfigCondition,
 	value?: Value
 ) => RuleOutcome;
+
+/**
+ * Rules always have a severity.
+ * Severity indicates what to do if the rule is found to be broken
+ * 0 - Disable this rule
+ * 1 - Warn for violations
+ * 2 - Error for violations
+ */
+export enum RuleConfigSeverity {
+	Disabled = 0,
+	Warning = 1,
+	Error = 2
+}
+
+/**
+ * Rules always have a condition.
+ * It can be either "always" (as tested), or "never" (as tested).
+ * For example, `header-full-stop` can be enforced as "always" or "never".
+ */
+export type RuleConfigCondition = 'always' | 'never';
+
+export type RuleConfigTuple<T> = T extends void
+	?
+			| Readonly<[RuleConfigSeverity.Disabled]>
+			| Readonly<[RuleConfigSeverity, RuleConfigCondition]>
+	:
+			| Readonly<[RuleConfigSeverity.Disabled]>
+			| Readonly<[RuleConfigSeverity, RuleConfigCondition, T]>;
+
+export enum RuleConfigQuality {
+	User,
+	Qualified
+}
+
+export type QualifiedRuleConfig<T> =
+	| (() => RuleConfigTuple<T>)
+	| (() => RuleConfigTuple<Promise<T>>)
+	| RuleConfigTuple<T>;
+
+export type RuleConfig<
+	V = RuleConfigQuality.Qualified,
+	T = void
+> = V extends RuleConfigQuality.Qualified
+	? RuleConfigTuple<T>
+	: QualifiedRuleConfig<T>;
+
+export type CaseRuleConfig<V = RuleConfigQuality.User> = RuleConfig<
+	V,
+	TargetCaseType
+>;
+export type LengthRuleConfig<V = RuleConfigQuality.User> = RuleConfig<
+	V,
+	number
+>;
+export type EnumRuleConfig<V = RuleConfigQuality.User> = RuleConfig<
+	V,
+	string[]
+>;
+
+export type RulesConfig<V = RuleConfigQuality.User> = {
+	'body-case': CaseRuleConfig<V>;
+	'body-empty': RuleConfig<V>;
+	'body-leading-blank': RuleConfig<V>;
+	'body-max-length': LengthRuleConfig<V>;
+	'body-max-line-length': LengthRuleConfig<V>;
+	'body-min-length': LengthRuleConfig<V>;
+	'footer-empty': RuleConfig<V>;
+	'footer-leading-blank': RuleConfig<V>;
+	'footer-max-length': LengthRuleConfig<V>;
+	'footer-max-line-length': LengthRuleConfig<V>;
+	'footer-min-length': LengthRuleConfig<V>;
+	'header-case': CaseRuleConfig<V>;
+	'header-full-stop': RuleConfig<V>;
+	'header-max-length': LengthRuleConfig<V>;
+	'header-min-length': LengthRuleConfig<V>;
+	'references-empty': RuleConfig<V>;
+	'scope-case': CaseRuleConfig<V>;
+	'scope-empty': RuleConfig<V>;
+	'scope-enum': EnumRuleConfig<V>;
+	'scope-max-length': LengthRuleConfig<V>;
+	'scope-min-length': LengthRuleConfig<V>;
+	'signed-off-by': RuleConfig<V>;
+	'subject-case': CaseRuleConfig<V>;
+	'subject-empty': RuleConfig<V>;
+	'subject-full-stop': RuleConfig<V>;
+	'subject-max-length': LengthRuleConfig<V>;
+	'subject-min-length': LengthRuleConfig<V>;
+	'type-case': CaseRuleConfig<V>;
+	'type-empty': RuleConfig<V>;
+	'type-enum': EnumRuleConfig<V>;
+	'type-max-length': LengthRuleConfig<V>;
+	'type-min-length': LengthRuleConfig<V>;
+	// Plugins may add their custom rules
+	[key: string]: AnyRuleConfig<V>;
+};
+
+export type AnyRuleConfig<V> = RuleConfig<V, unknown> | RuleConfig<V, void>;
diff --git a/yarn.lock b/yarn.lock
index 4d9a5458b5..fc08bf2455 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1893,6 +1893,13 @@
   resolved "https://registry.npmjs.org/@types/events/-/events-3.0.0.tgz#2862f3f58a9a7f7c3e78d79f130dd4d71c25c2a7"
   integrity sha512-EaObqwIvayI5a8dCzhFrjKzVwKLxjoG9T6Ppd5CEo07LRKfQ8Yokw54r5+Wq7FaBQ+yXRvQAYPrHwya1/UFt9g==
 
+"@types/execa@^0.9.0":
+  version "0.9.0"
+  resolved "https://registry.npmjs.org/@types/execa/-/execa-0.9.0.tgz#9b025d2755f17e80beaf9368c3f4f319d8b0fb93"
+  integrity sha512-mgfd93RhzjYBUHHV532turHC2j4l/qxsF/PbfDmprHDEUHmNZGlDn1CEsulGK3AfsPdhkWzZQT/S/k0UGhLGsA==
+  dependencies:
+    "@types/node" "*"
+
 "@types/fs-extra@^8.0.1":
   version "8.0.1"
   resolved "https://registry.npmjs.org/@types/fs-extra/-/fs-extra-8.0.1.tgz#a2378d6e7e8afea1564e44aafa2e207dadf77686"
@@ -8571,7 +8578,7 @@ resolve@1.1.7:
   resolved "https://registry.npmjs.org/resolve/-/resolve-1.1.7.tgz#203114d82ad2c5ed9e8e0411b3932875e889e97b"
   integrity sha1-IDEU2CrSxe2ejgQRs5ModeiJ6Xs=
 
-resolve@1.x, resolve@^1.1.6, resolve@^1.10.0, resolve@^1.3.2, resolve@^1.8.1, resolve@^1.12.0, resolve@^1.13.1:
+resolve@1.x, resolve@^1.1.6, resolve@^1.10.0, resolve@^1.12.0, resolve@^1.13.1, resolve@^1.3.2, resolve@^1.8.1:
   version "1.15.1"
   resolved "https://registry.npmjs.org/resolve/-/resolve-1.15.1.tgz#27bdcdeffeaf2d6244b95bb0f9f4b4653451f3e8"
   integrity sha512-84oo6ZTtoTUpjgNEr5SJyzQhzL72gaRodsSfyxC/AXRvwu0Yse9H8eF9IpGo7b8YetZhlI6v7ZQ6bKBFV/6S7w==