diff --git a/package.json b/package.json
index f7c962925..c66c9af5f 100644
--- a/package.json
+++ b/package.json
@@ -11,6 +11,7 @@
     "bundle-collapser": "^1.3.0",
     "camelcase": "^5.0.0",
     "clone": "^2.0.0",
+    "dtslint": "^0.4.2",
     "lerna": "^3.0.0",
     "mdast-util-assert": "^2.0.0",
     "mdast-util-compact": "^1.0.0",
@@ -20,20 +21,22 @@
     "remark-preset-wooorm": "^5.0.0",
     "tape": "^4.5.1",
     "tinyify": "^2.4.3",
+    "typescript": "^3.2.4",
     "unist-builder": "^1.0.2",
     "unist-util-remove-position": "^1.1.0",
     "xo": "^0.24.0"
   },
   "scripts": {
     "postinstall": "lerna bootstrap --no-ci",
-    "format": "packages/remark-cli/cli.js . -qfo && prettier --write \"**/*.js\" && xo --fix",
+    "format": "packages/remark-cli/cli.js . -qfo && prettier --write \"**/*.{js,ts}\" && xo --fix",
     "build-bundle": "browserify packages/remark -s remark > remark.js",
     "build-mangle": "browserify packages/remark -s remark -p tinyify > remark.min.js",
     "build": "npm run build-bundle && npm run build-mangle",
     "test-api": "tape packages/*/test.js test/index.js",
     "test-api-extensive": "TEST_EXTENDED=true npm run test-api",
     "test-coverage": "nyc --reporter lcov tape \"test/index.js\" \"packages/*/test.js\"",
-    "test": "npm run format && npm run build && npm run test-coverage"
+    "test-types": "dtslint packages/remark-parse/types && dtslint packages/remark-stringify/types && dtslint packages/remark/types",
+    "test": "npm run format && npm run build && npm run test-coverage && npm run test-types"
   },
   "nyc": {
     "check-coverage": true,
diff --git a/packages/remark-parse/package.json b/packages/remark-parse/package.json
index 631128d99..6d4553ff3 100644
--- a/packages/remark-parse/package.json
+++ b/packages/remark-parse/package.json
@@ -15,6 +15,7 @@
     "ast",
     "parse"
   ],
+  "types": "types/index.d.ts",
   "homepage": "https://remark.js.org",
   "repository": "https://github.com/remarkjs/remark/tree/master/packages/remark-parse",
   "bugs": "https://github.com/remarkjs/remark/issues",
@@ -28,7 +29,8 @@
   ],
   "files": [
     "index.js",
-    "lib"
+    "lib",
+    "types/index.d.ts"
   ],
   "dependencies": {
     "collapse-white-space": "^1.0.2",
@@ -49,7 +51,7 @@
   },
   "devDependencies": {
     "tape": "^4.9.1",
-    "unified": "^8.0.0",
+    "unified": "^8.2.0",
     "vfile": "^4.0.0"
   },
   "scripts": {
diff --git a/packages/remark-parse/types/index.d.ts b/packages/remark-parse/types/index.d.ts
new file mode 100644
index 000000000..c8eff9ff0
--- /dev/null
+++ b/packages/remark-parse/types/index.d.ts
@@ -0,0 +1,53 @@
+// TypeScript Version: 3.0
+
+import {Node, Parent, Position} from 'unist'
+import {Parser, Attacher} from 'unified'
+
+declare class RemarkParser implements Parser {
+  parse(): Node
+  blockMethods: string[]
+  inlineTokenizers: {
+    [key: string]: remarkParse.Tokenizer
+  }
+  inlineMethods: string[]
+}
+
+declare namespace remarkParse {
+  interface Parse extends Attacher<[Partial<RemarkParseOptions>]> {
+    (options: Partial<RemarkParseOptions>): void
+    Parser: typeof RemarkParser
+  }
+
+  type Parser = RemarkParser
+
+  interface RemarkParseOptions {
+    gfm: boolean
+    commonmark: boolean
+    footnotes: boolean
+    blocks: string[]
+    pedantic: boolean
+  }
+
+  interface Add {
+    (node: Node, parent?: Parent): Node
+    test(): Position
+    reset(node: Node, parent?: Node): Node
+  }
+
+  type Eat = (value: string) => Add
+
+  type Locator = (value: string, fromIndex: number) => number
+
+  interface Tokenizer {
+    (eat: Eat, value: string, silent: true): boolean | void
+    (eat: Eat, value: string): Node | void
+    locator?: Locator
+    onlyAtStart?: boolean
+    notInBlock?: boolean
+    notInList?: boolean
+    notInLink?: boolean
+  }
+}
+declare const remarkParse: remarkParse.Parse
+
+export = remarkParse
diff --git a/packages/remark-parse/types/test.ts b/packages/remark-parse/types/test.ts
new file mode 100644
index 000000000..99a6a8315
--- /dev/null
+++ b/packages/remark-parse/types/test.ts
@@ -0,0 +1,17 @@
+import unified = require('unified')
+import * as Unist from 'unist'
+import remarkParse = require('remark-parse')
+
+const parseOptions = {
+  gfm: true,
+  pedantic: true
+}
+
+unified().use(remarkParse, parseOptions)
+
+const badParseOptions = {
+  gfm: 'true'
+}
+
+// $ExpectError
+unified().use(remarkParse, badParseOptions)
diff --git a/packages/remark-parse/types/tsconfig.json b/packages/remark-parse/types/tsconfig.json
new file mode 100644
index 000000000..9680afacc
--- /dev/null
+++ b/packages/remark-parse/types/tsconfig.json
@@ -0,0 +1,14 @@
+{
+  "compilerOptions": {
+    "lib": ["es2015"],
+    "strict": true,
+    "noImplicitAny": true,
+    "noImplicitThis": true,
+    "strictNullChecks": true,
+    "strictFunctionTypes": true,
+    "baseUrl": ".",
+    "paths": {
+      "remark-parse": ["index.d.ts"]
+    }
+  }
+}
diff --git a/packages/remark-parse/types/tslint.json b/packages/remark-parse/types/tslint.json
new file mode 100644
index 000000000..22174ee66
--- /dev/null
+++ b/packages/remark-parse/types/tslint.json
@@ -0,0 +1,14 @@
+{
+  "extends": "dtslint/dtslint.json",
+  "rules": {
+    "callable-types": false,
+    "max-line-length": false,
+    "no-redundant-jsdoc": false,
+    "no-void-expression": false,
+    "only-arrow-functions": false,
+    "semicolon": false,
+    "unified-signatures": false,
+    "whitespace": false,
+    "interface-over-type-literal": false
+  }
+}
diff --git a/packages/remark-stringify/package.json b/packages/remark-stringify/package.json
index b31af4e40..410053a8d 100644
--- a/packages/remark-stringify/package.json
+++ b/packages/remark-stringify/package.json
@@ -26,8 +26,10 @@
   ],
   "files": [
     "index.js",
-    "lib"
+    "lib",
+    "types/index.d.ts"
   ],
+  "types": "types/index.d.ts",
   "dependencies": {
     "ccount": "^1.0.0",
     "is-alphanumeric": "^1.0.0",
@@ -46,7 +48,7 @@
   },
   "devDependencies": {
     "tape": "^4.9.1",
-    "unified": "^8.0.0",
+    "unified": "^8.2.0",
     "unist-builder": "^1.0.3",
     "unist-util-visit": "^1.4.0",
     "wcwidth": "^1.0.1"
diff --git a/packages/remark-stringify/types/index.d.ts b/packages/remark-stringify/types/index.d.ts
new file mode 100644
index 000000000..1f1fa6891
--- /dev/null
+++ b/packages/remark-stringify/types/index.d.ts
@@ -0,0 +1,48 @@
+// TypeScript Version: 3.0
+
+import {Attacher, Compiler, Processor} from 'unified'
+import {Node, Parent} from 'unist'
+
+declare class RemarkCompiler implements Compiler {
+  compile(): string
+  visitors: {
+    [key: string]: remarkStringify.Visitor
+  }
+}
+
+declare namespace remarkStringify {
+  interface Stringify extends Attacher<[Partial<RemarkStringifyOptions>]> {
+    Compiler: typeof RemarkCompiler
+    (this: Processor, options?: Partial<RemarkStringifyOptions>): void
+  }
+
+  type Compiler = RemarkCompiler
+
+  interface RemarkStringifyOptions {
+    gfm: boolean
+    commonmark: boolean
+    entities: boolean | 'numbers' | 'escape'
+    setext: boolean
+    closeAtx: boolean
+    looseTable: boolean
+    spacedTable: boolean
+    paddedTable: boolean
+    stringLength: (s: string) => number
+    fence: '~' | '`'
+    fences: boolean
+    bullet: '-' | '*' | '+'
+    listItemIndent: 'tab' | '1' | 'mixed'
+    incrementListMarker: boolean
+    rule: '-' | '_' | '*'
+    ruleRepetition: number
+    ruleSpaces: boolean
+    strong: '_' | '*'
+    emphasis: '_' | '*'
+  }
+
+  type Visitor = (node: Node, parent?: Parent) => string
+}
+
+declare const remarkStringify: remarkStringify.Stringify
+
+export = remarkStringify
diff --git a/packages/remark-stringify/types/test.ts b/packages/remark-stringify/types/test.ts
new file mode 100644
index 000000000..4e9befbae
--- /dev/null
+++ b/packages/remark-stringify/types/test.ts
@@ -0,0 +1,51 @@
+import remarkStringify = require('remark-stringify')
+import unified = require('unified')
+import {Node, Parent} from 'unist'
+
+const inferredStringifyOptions = {
+  gfm: true,
+  fences: true,
+  incrementListMarker: false
+}
+
+unified().use(remarkStringify, inferredStringifyOptions)
+
+// These cannot be automatically inferred by TypeScript
+const nonInferredStringifyOptions: Partial<
+  remarkStringify.RemarkStringifyOptions
+> = {
+  fence: '~',
+  bullet: '+',
+  listItemIndent: 'tab',
+  rule: '-',
+  strong: '_',
+  emphasis: '*'
+}
+
+unified().use(remarkStringify, nonInferredStringifyOptions)
+
+const badStringifyOptions = {
+  gfm: 'true'
+}
+
+// $ExpectError
+unified().use(remarkStringify, badStringifyOptions)
+
+function gap(this: unified.Processor) {
+  const Compiler = this.Compiler as typeof remarkStringify.Compiler
+  const visitors = Compiler.prototype.visitors
+  const original = visitors.heading
+
+  visitors.heading = heading
+
+  function heading(this: unified.Processor, node: Node, parent?: Parent) {
+    // FIXME: remove need for explicit 'as' casting
+    const headingNode = node as (Node & {depth: number})
+    return (
+      (headingNode.depth === 2 ? '\n' : '') +
+      original.apply(this, [node, parent])
+    )
+  }
+}
+
+const plugin: unified.Attacher = gap
diff --git a/packages/remark-stringify/types/tsconfig.json b/packages/remark-stringify/types/tsconfig.json
new file mode 100644
index 000000000..91a76bf11
--- /dev/null
+++ b/packages/remark-stringify/types/tsconfig.json
@@ -0,0 +1,14 @@
+{
+  "compilerOptions": {
+    "lib": ["es2015"],
+    "strict": true,
+    "noImplicitAny": true,
+    "noImplicitThis": true,
+    "strictNullChecks": true,
+    "strictFunctionTypes": true,
+    "baseUrl": ".",
+    "paths": {
+      "remark-stringify": ["index.d.ts"]
+    }
+  }
+}
diff --git a/packages/remark-stringify/types/tslint.json b/packages/remark-stringify/types/tslint.json
new file mode 100644
index 000000000..22174ee66
--- /dev/null
+++ b/packages/remark-stringify/types/tslint.json
@@ -0,0 +1,14 @@
+{
+  "extends": "dtslint/dtslint.json",
+  "rules": {
+    "callable-types": false,
+    "max-line-length": false,
+    "no-redundant-jsdoc": false,
+    "no-void-expression": false,
+    "only-arrow-functions": false,
+    "semicolon": false,
+    "unified-signatures": false,
+    "whitespace": false,
+    "interface-over-type-literal": false
+  }
+}
diff --git a/packages/remark/package.json b/packages/remark/package.json
index cd3b60280..522a6423b 100644
--- a/packages/remark/package.json
+++ b/packages/remark/package.json
@@ -24,12 +24,14 @@
     "Titus Wormer <tituswormer@gmail.com> (https://wooorm.com)"
   ],
   "files": [
-    "index.js"
+    "index.js",
+    "types/index.d.ts"
   ],
+  "types": "types/index.d.ts",
   "dependencies": {
     "remark-parse": "^6.0.0",
     "remark-stringify": "^6.0.0",
-    "unified": "^8.0.0"
+    "unified": "^8.2.0"
   },
   "devDependencies": {
     "tape": "^4.9.1"
diff --git a/packages/remark/types/index.d.ts b/packages/remark/types/index.d.ts
new file mode 100644
index 000000000..10f33a901
--- /dev/null
+++ b/packages/remark/types/index.d.ts
@@ -0,0 +1,14 @@
+// TypeScript Version: 3.0
+
+import unified = require('unified')
+import remarkParse = require('remark-parse')
+import remarkStringify = require('remark-stringify')
+
+type RemarkOptions = remarkParse.RemarkParseOptions &
+  remarkStringify.RemarkStringifyOptions
+
+declare function remark<
+  P extends Partial<RemarkOptions> = Partial<RemarkOptions>
+>(): unified.Processor<P>
+
+export = remark
diff --git a/packages/remark/types/test.ts b/packages/remark/types/test.ts
new file mode 100644
index 000000000..e4ef0e845
--- /dev/null
+++ b/packages/remark/types/test.ts
@@ -0,0 +1,15 @@
+import remark = require('remark')
+
+interface PluginOptions {
+  example: boolean
+}
+
+const plugin = (options?: PluginOptions) => {}
+
+remark().use(plugin)
+remark().use(plugin, {example: true})
+remark().use({settings: {commonmark: true}})
+// $ExpectError
+remark().use({settings: {doesNotExist: true}})
+// $ExpectError
+remark().use(plugin, {doesNotExist: 'true'})
diff --git a/packages/remark/types/tsconfig.json b/packages/remark/types/tsconfig.json
new file mode 100644
index 000000000..c688cea16
--- /dev/null
+++ b/packages/remark/types/tsconfig.json
@@ -0,0 +1,14 @@
+{
+  "compilerOptions": {
+    "lib": ["es2015"],
+    "strict": true,
+    "noImplicitAny": true,
+    "noImplicitThis": true,
+    "strictNullChecks": true,
+    "strictFunctionTypes": true,
+    "baseUrl": ".",
+    "paths": {
+      "remark": ["index.d.ts"]
+    }
+  }
+}
diff --git a/packages/remark/types/tslint.json b/packages/remark/types/tslint.json
new file mode 100644
index 000000000..aa595811d
--- /dev/null
+++ b/packages/remark/types/tslint.json
@@ -0,0 +1,15 @@
+{
+  "extends": "dtslint/dtslint.json",
+  "rules": {
+    "callable-types": false,
+    "max-line-length": false,
+    "no-redundant-jsdoc": false,
+    "no-void-expression": false,
+    "only-arrow-functions": false,
+    "semicolon": false,
+    "unified-signatures": false,
+    "whitespace": false,
+    "interface-over-type-literal": false,
+    "no-unnecessary-generics": false
+  }
+}