diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..5330070
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,177 @@
+# Based on https://raw.githubusercontent.com/github/gitignore/main/Node.gitignore
+
+dist/
+
+# Logs
+
+logs
+_.log
+npm-debug.log_
+yarn-debug.log*
+yarn-error.log*
+lerna-debug.log*
+.pnpm-debug.log*
+
+# Caches
+
+.cache
+
+# Diagnostic reports (https://nodejs.org/api/report.html)
+
+report.[0-9]_.[0-9]_.[0-9]_.[0-9]_.json
+
+# Runtime data
+
+pids
+_.pid
+_.seed
+*.pid.lock
+
+# Directory for instrumented libs generated by jscoverage/JSCover
+
+lib-cov
+
+# Coverage directory used by tools like istanbul
+
+coverage
+*.lcov
+
+# nyc test coverage
+
+.nyc_output
+
+# Grunt intermediate storage (https://gruntjs.com/creating-plugins#storing-task-files)
+
+.grunt
+
+# Bower dependency directory (https://bower.io/)
+
+bower_components
+
+# node-waf configuration
+
+.lock-wscript
+
+# Compiled binary addons (https://nodejs.org/api/addons.html)
+
+build/Release
+
+# Dependency directories
+
+node_modules/
+jspm_packages/
+
+# Snowpack dependency directory (https://snowpack.dev/)
+
+web_modules/
+
+# TypeScript cache
+
+*.tsbuildinfo
+
+# Optional npm cache directory
+
+.npm
+
+# Optional eslint cache
+
+.eslintcache
+
+# Optional stylelint cache
+
+.stylelintcache
+
+# Microbundle cache
+
+.rpt2_cache/
+.rts2_cache_cjs/
+.rts2_cache_es/
+.rts2_cache_umd/
+
+# Optional REPL history
+
+.node_repl_history
+
+# Output of 'npm pack'
+
+*.tgz
+
+# Yarn Integrity file
+
+.yarn-integrity
+
+# dotenv environment variable files
+
+.env
+.env.development.local
+.env.test.local
+.env.production.local
+.env.local
+
+# parcel-bundler cache (https://parceljs.org/)
+
+.parcel-cache
+
+# Next.js build output
+
+.next
+out
+
+# Nuxt.js build / generate output
+
+.nuxt
+dist
+
+# Gatsby files
+
+# Comment in the public line in if your project uses Gatsby and not Next.js
+
+# https://nextjs.org/blog/next-9-1#public-directory-support
+
+# public
+
+# vuepress build output
+
+.vuepress/dist
+
+# vuepress v2.x temp and cache directory
+
+.temp
+
+# Docusaurus cache and generated files
+
+.docusaurus
+
+# Serverless directories
+
+.serverless/
+
+# FuseBox cache
+
+.fusebox/
+
+# DynamoDB Local files
+
+.dynamodb/
+
+# TernJS port file
+
+.tern-port
+
+# Stores VSCode versions used for testing VSCode extensions
+
+.vscode-test
+
+# yarn v2
+
+.yarn/cache
+.yarn/unplugged
+.yarn/build-state.yml
+.yarn/install-state.gz
+.pnp.*
+
+# IntelliJ based IDEs
+.idea
+
+# Finder (MacOS) folder config
+.DS_Store
diff --git a/.npmignore b/.npmignore
new file mode 100644
index 0000000..f679b49
--- /dev/null
+++ b/.npmignore
@@ -0,0 +1,25 @@
+.git
+.github
+.gitignore
+.prettierrc
+.cjs.swcrc
+.es.swcrc
+bun.lockb
+
+node_modules
+tsconfig.json
+pnpm-lock.yaml
+jest.config.js
+nodemon.json
+
+tests
+src
+test
+CHANGELOG.md
+.eslintrc.js
+tsconfig.cjs.json
+tsconfig.esm.json
+tsconfig.dts.json
+
+build.ts
+src
diff --git a/.vscode/settings.json b/.vscode/settings.json
new file mode 100644
index 0000000..9c2a3aa
--- /dev/null
+++ b/.vscode/settings.json
@@ -0,0 +1,12 @@
+{
+  "editor.formatOnSave": true,
+  "[javascript]": {
+    "editor.defaultFormatter": "biomejs.biome"
+  },
+  "[typescript]": {
+    "editor.defaultFormatter": "biomejs.biome"
+  },
+  "[json]": {
+    "editor.defaultFormatter": "biomejs.biome"
+  }
+}
diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..5df146a
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2024 Igor Morozov
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..49a9992
--- /dev/null
+++ b/README.md
@@ -0,0 +1,109 @@
+# elysia-accepts
+
+Plugin for [Elysia](https://github.com/elysiajs/elysia) for content negotiation based on Accept headers based on `@tinyhttp/accepts` which is based on old good `negotiator`.
+
+## Installation
+
+```sh
+bun a elysia-accepts
+```
+
+```ts
+import { accepts } from "elysia-accepts";
+
+const app = new Elysia()
+  .use(accepts());
+```
+
+No options currently available and plugin is always registered in global scope.
+
+## Context
+
+### Type
+
+```ts
+const app = new Elysia()
+  .use(accepts())
+  .get("/", (ctx) => ctx.type("text/html")); // Returns "html" if acceptable
+```
+
+```ts
+const app = new Elysia()
+  .use(accepts())
+  .get("/", (ctx) => ctx.type(["text/html", "application/json"]));
+  // Returns the first acceptable or false if none
+```
+
+```ts
+const app = new Elysia()
+  .use(accepts())
+  .get("/", (ctx) => ctx.type(["html", "json"]));
+  // Can pass file extension. In this case "html" returned if acceptable.
+```
+
+```ts
+const app = new Elysia()
+  .use(accepts())
+  .get("/", (ctx) => ctx.types); // Returns the list of all acceptable encodings
+```
+
+### Encoding
+
+```ts
+const app = new Elysia()
+  .use(accepts())
+  .get("/", (ctx) => ctx.encoding("gzip")); // Returns "gzip" if acceptable
+```
+
+```ts
+const app = new Elysia()
+  .use(accepts())
+  .get("/", (ctx) => ctx.encoding(["gzip", "deflate"])); // Returns the first acceptable or false if none
+```
+
+```ts
+const app = new Elysia()
+  .use(accepts())
+  .get("/", (ctx) => ctx.encodings); // Returns the list of all acceptable encodings
+```
+
+### Languages
+
+```ts
+const app = new Elysia()
+  .use(accepts())
+  .get("/", (ctx) => ctx.language("en")); // Returns "en" if acceptable
+```
+
+```ts
+const app = new Elysia()
+  .use(accepts())
+  .get("/", (ctx) => ctx.language(["en", "ru"])); // Returns the first acceptable or false if none
+```
+
+```ts
+const app = new Elysia()
+  .use(accepts())
+  .get("/", (ctx) => ctx.languages); // Returns the list of all acceptable languages
+```
+
+## Guard
+
+### Per Route
+
+```ts
+const app = new Elysia()
+  .use(accepts())
+  .get("/", (ctx) => 'hi', { types: ['text/plain'] });
+  // Returns 406 if plain text is not acceptable
+```
+
+### Global
+
+```ts
+const app = new Elysia()
+  .use(accepts())
+  .guard({ types: ['text/plain'] })
+  .get("/", (ctx) => 'hi');
+  // Returns 406 if plain text is not acceptable
+```
diff --git a/biome.json b/biome.json
new file mode 100644
index 0000000..57aab2b
--- /dev/null
+++ b/biome.json
@@ -0,0 +1,28 @@
+{
+  "$schema": "https://biomejs.dev/schemas/1.8.3/schema.json",
+  "vcs": {
+    "enabled": true,
+    "clientKind": "git",
+    "useIgnoreFile": true
+  },
+  "organizeImports": {
+    "enabled": true
+  },
+  "linter": {
+    "enabled": true,
+    "rules": {
+      "recommended": true
+    }
+  },
+  "formatter": {
+    "indentStyle": "space",
+    "indentWidth": 2
+  },
+  "json": {
+    "formatter": {
+      "trailingCommas": "none",
+      "indentStyle": "space",
+      "indentWidth": 4
+    }
+  }
+}
diff --git a/build.ts b/build.ts
new file mode 100644
index 0000000..ef8794e
--- /dev/null
+++ b/build.ts
@@ -0,0 +1,37 @@
+import { $ } from "bun";
+import { build, type Options } from "tsup";
+
+await $`rm -rf dist`;
+
+const tsupConfig: Options = {
+  entry: ["src/**/*.ts"],
+  splitting: false,
+  sourcemap: false,
+  clean: true,
+  bundle: true,
+} satisfies Options;
+
+await Promise.all([
+  // ? tsup esm
+  build({
+    outDir: "dist",
+    format: "esm",
+    target: "node20",
+    cjsInterop: false,
+    ...tsupConfig,
+  }),
+  // ? tsup cjs
+  build({
+    outDir: "dist/cjs",
+    format: "cjs",
+    target: "node20",
+    // dts: true,
+    ...tsupConfig,
+  }),
+]);
+
+await $`tsc --project tsconfig.dts.json`;
+
+await Promise.all([$`cp dist/*.d.ts dist/cjs`]);
+
+process.exit();
diff --git a/bun.lockb b/bun.lockb
new file mode 100755
index 0000000..b20b319
Binary files /dev/null and b/bun.lockb differ
diff --git a/package.json b/package.json
new file mode 100644
index 0000000..4432bfd
--- /dev/null
+++ b/package.json
@@ -0,0 +1,48 @@
+{
+    "name": "elysia-accepts",
+    "description": "Elysia plugin for accept headers parsing and content negotiation",
+    "version": "1.0.0",
+    "author": {
+        "name": "Igor Morozov",
+        "url": "https://github.com/morigs",
+        "email": "morozov.ig.s@gmail.com"
+    },
+    "repository": {
+        "type": "git",
+        "url": "https://github.com/morigs/elysia-accepts"
+    },
+    "main": "./dist/cjs/index.js",
+    "module": "./dist/index.mjs",
+    "types": "./dist/index.d.ts",
+    "exports": {
+        "./package.json": "./package.json",
+        ".": {
+            "types": "./dist/index.d.ts",
+            "import": "./dist/index.mjs",
+            "require": "./dist/cjs/index.js"
+        }
+    },
+    "bugs": "https://github.com/morigs/elysia-accepts/issues",
+    "homepage": "https://github.com/morigs/elysia-accepts",
+    "keywords": ["elysia", "accept", "negotiation"],
+    "license": "MIT",
+    "scripts": {
+        "test": "bun test",
+        "build": "bun build.ts",
+        "lint": "biome lint",
+        "release": "npm run build && npm run test && npm publish --access public"
+    },
+    "devDependencies": {
+        "@biomejs/biome": "^1.8.3",
+        "@types/bun": "latest",
+        "elysia": "^1.1.4",
+        "tsup": "^8.2.3"
+    },
+    "peerDependencies": {
+        "typescript": "^5.0.0",
+        "elysia": "^1.1.4"
+    },
+    "dependencies": {
+        "@tinyhttp/accepts": "^2.2.2"
+    }
+}
diff --git a/src/accept.spec.ts b/src/accept.spec.ts
new file mode 100644
index 0000000..03ea91e
--- /dev/null
+++ b/src/accept.spec.ts
@@ -0,0 +1,320 @@
+import { expect, test, describe } from "bun:test";
+import Elysia from "elysia";
+import { accepts } from ".";
+
+describe("accept context", () => {
+  describe("charset", () => {
+    test("should return the first accepted charset", async () => {
+      const app = new Elysia()
+        .use(accepts())
+        .get("/", (ctx) => ctx.charset("utf-8"));
+
+      const req = new Request("http://localhost/", {
+        headers: { "accept-charset": "*" },
+      });
+      const res = await app.handle(req).then((res) => res.text());
+
+      expect(res).toBe("utf-8");
+    });
+
+    test("should return false when nothing is accepted", async () => {
+      const app = new Elysia()
+        .use(accepts())
+        .get("/", (ctx) => ctx.charset("utf-8"));
+
+      const req = new Request("http://localhost/", {
+        headers: { "accept-charset": "unknown" },
+      });
+      const res = await app.handle(req).then((res) => res.text());
+
+      expect(res).toBe("false");
+    });
+
+    test("should return list when no params", async () => {
+      const app = new Elysia().use(accepts()).get("/", (ctx) => ctx.charset);
+
+      const req = new Request("http://localhost/", {
+        headers: { "accept-charset": "utf8, win1251" },
+      });
+      const res = await app.handle(req).then((res) => res.json());
+
+      expect(res).toEqual(["utf8", "win1251"]);
+    });
+
+    test("should return list", async () => {
+      const app = new Elysia().use(accepts()).get("/", (ctx) => ctx.charsets);
+
+      const req = new Request("http://localhost/", {
+        headers: { "accept-charset": "utf8, win1251" },
+      });
+      const res = await app.handle(req).then((res) => res.json());
+
+      expect(res).toEqual(["utf8", "win1251"]);
+    });
+  });
+
+  describe("language", () => {
+    test("should return the first accepted language", async () => {
+      const app = new Elysia()
+        .use(accepts())
+        .get("/", (ctx) => ctx.language("en"));
+
+      const req = new Request("http://localhost/", {
+        headers: { "accept-language": "ru, en" },
+      });
+      const res = await app.handle(req).then((res) => res.text());
+
+      expect(res).toBe("en");
+    });
+
+    test("should return false when nothing is accepted", async () => {
+      const app = new Elysia()
+        .use(accepts())
+        .get("/", (ctx) => ctx.language("en"));
+
+      const req = new Request("http://localhost/", {
+        headers: { "accept-language": "ru" },
+      });
+      const res = await app.handle(req).then((res) => res.text());
+
+      expect(res).toBe("false");
+    });
+
+    test("should return list when no params", async () => {
+      const app = new Elysia().use(accepts()).get("/", (ctx) => ctx.language);
+
+      const req = new Request("http://localhost/", {
+        headers: { "accept-language": "ru, en" },
+      });
+      const res = await app.handle(req).then((res) => res.json());
+
+      expect(res).toEqual(["ru", "en"]);
+    });
+
+    test("should return list", async () => {
+      const app = new Elysia().use(accepts()).get("/", (ctx) => ctx.languages);
+
+      const req = new Request("http://localhost/", {
+        headers: { "accept-language": "ru, en" },
+      });
+      const res = await app.handle(req).then((res) => res.json());
+
+      expect(res).toEqual(["ru", "en"]);
+    });
+  });
+
+  describe("encoding", () => {
+    test("should return the first accepted encoding", async () => {
+      const app = new Elysia()
+        .use(accepts())
+        .get("/", (ctx) => ctx.encoding("gzip"));
+
+      const req = new Request("http://localhost/", {
+        headers: { "accept-encoding": "deflate, gzip" },
+      });
+      const res = await app.handle(req).then((res) => res.text());
+
+      expect(res).toBe("gzip");
+    });
+
+    test("should return false when nothing is accepted", async () => {
+      const app = new Elysia()
+        .use(accepts())
+        .get("/", (ctx) => ctx.encoding("gzip"));
+
+      const req = new Request("http://localhost/", {
+        headers: { "accept-encoding": "deflate" },
+      });
+      const res = await app.handle(req).then((res) => res.text());
+
+      expect(res).toBe("false");
+    });
+
+    test("should return list with identity when no params", async () => {
+      const app = new Elysia().use(accepts()).get("/", (ctx) => ctx.encoding);
+
+      const req = new Request("http://localhost/", {
+        headers: { "accept-encoding": "deflate, gzip" },
+      });
+      const res = await app.handle(req).then((res) => res.json());
+
+      expect(res).toEqual(["deflate", "gzip", "identity"]);
+    });
+
+    test("should return list with identity", async () => {
+      const app = new Elysia().use(accepts()).get("/", (ctx) => ctx.encodings);
+
+      const req = new Request("http://localhost/", {
+        headers: { "accept-encoding": "deflate, gzip" },
+      });
+      const res = await app.handle(req).then((res) => res.json());
+
+      expect(res).toEqual(["deflate", "gzip", "identity"]);
+    });
+  });
+
+  describe("type", () => {
+    test("should return the first accepted type", async () => {
+      const app = new Elysia()
+        .use(accepts())
+        .get("/", (ctx) => ctx.type("text/html"));
+
+      const req = new Request("http://localhost/", {
+        headers: { accept: "text/html, application/json" },
+      });
+      const res = await app.handle(req).then((res) => res.text());
+
+      expect(res).toBe("text/html");
+    });
+
+    test("should return the first accepted type for star", async () => {
+      const app = new Elysia()
+        .use(accepts())
+        .get("/", (ctx) => ctx.type("text/html"));
+
+      const req = new Request("http://localhost/", {
+        headers: { accept: "*/*" },
+      });
+      const res = await app.handle(req).then((res) => res.text());
+
+      expect(res).toBe("text/html");
+    });
+
+    test("should return the first accepted type in short form", async () => {
+      const app = new Elysia()
+        .use(accepts())
+        .get("/", (ctx) => ctx.type("json"));
+
+      const req = new Request("http://localhost/", {
+        headers: { accept: "text/html, application/json" },
+      });
+      const res = await app.handle(req).then((res) => res.text());
+
+      expect(res).toBe("json");
+    });
+
+    test("should return false when nothing is accepted", async () => {
+      const app = new Elysia()
+        .use(accepts())
+        .get("/", (ctx) => ctx.type("xml"));
+
+      const req = new Request("http://localhost/", {
+        headers: { accept: "text/html, application/json" },
+      });
+      const res = await app.handle(req).then((res) => res.text());
+
+      expect(res).toBe("false");
+    });
+
+    test("should return list when no params", async () => {
+      const app = new Elysia().use(accepts()).get("/", (ctx) => ctx.type);
+
+      const req = new Request("http://localhost/", {
+        headers: { accept: "text/html, application/json" },
+      });
+      const res = await app.handle(req).then((res) => res.json());
+
+      expect(res).toEqual(["text/html", "application/json"]);
+    });
+
+    test("should return list", async () => {
+      const app = new Elysia().use(accepts()).get("/", (ctx) => ctx.types);
+
+      const req = new Request("http://localhost/", {
+        headers: { accept: "text/html, application/json" },
+      });
+      const res = await app.handle(req).then((res) => res.json());
+
+      expect(res).toEqual(["text/html", "application/json"]);
+    });
+  });
+});
+
+describe("guard", () => {
+  describe("per route", () => {
+    test("passes when type is accepted", async () => {
+      const app = new Elysia()
+        .use(accepts())
+        .get("/", () => "OK", { types: ["text/plain"] });
+
+      const req = new Request("http://localhost/", {
+        headers: { accept: "text/plain, application/json" },
+      });
+      const res = await app.handle(req).then((res) => res.text());
+
+      expect(res).toBe("OK");
+    });
+
+    test("passes for star", async () => {
+      const app = new Elysia()
+        .use(accepts())
+        .get("/", () => "OK", { types: ["text/plain"] });
+
+      const req = new Request("http://localhost/", {
+        headers: { accept: "*/*" },
+      });
+      const res = await app.handle(req).then((res) => res.text());
+
+      expect(res).toBe("OK");
+    });
+
+    test("406 when not accepted", async () => {
+      const app = new Elysia()
+        .use(accepts())
+        .get("/", () => "OK", { types: ["text/plain"] });
+
+      const req = new Request("http://localhost/", {
+        headers: { accept: "application/json" },
+      });
+      const res = await app.handle(req);
+
+      expect(res.status).toBe(406);
+      expect(res.text()).resolves.toBe("Not Acceptable");
+    });
+  });
+
+  describe("global", () => {
+    test("passes when type is accepted", async () => {
+      const app = new Elysia()
+        .use(accepts())
+        .guard({ types: ["text/plain"] })
+        .get("/", () => "OK");
+
+      const req = new Request("http://localhost/", {
+        headers: { accept: "text/plain, application/json" },
+      });
+      const res = await app.handle(req).then((res) => res.text());
+
+      expect(res).toBe("OK");
+    });
+
+    test("passes for star", async () => {
+      const app = new Elysia()
+        .use(accepts())
+        .guard({ types: ["text/plain"] })
+        .get("/", () => "OK");
+
+      const req = new Request("http://localhost/", {
+        headers: { accept: "*/*" },
+      });
+      const res = await app.handle(req).then((res) => res.text());
+
+      expect(res).toBe("OK");
+    });
+
+    test("406 when not accepted", async () => {
+      const app = new Elysia()
+        .use(accepts())
+        .guard({ types: ["text/plain"] })
+        .get("/", () => "OK");
+
+      const req = new Request("http://localhost/", {
+        headers: { accept: "application/json" },
+      });
+      const res = await app.handle(req);
+
+      expect(res.status).toBe(406);
+      expect(res.text()).resolves.toBe("Not Acceptable");
+    });
+  });
+});
diff --git a/src/index.ts b/src/index.ts
new file mode 100644
index 0000000..e38e8b2
--- /dev/null
+++ b/src/index.ts
@@ -0,0 +1,94 @@
+import Elysia from "elysia";
+import { Accepts } from "@tinyhttp/accepts";
+
+export function accepts() {
+  return new Elysia({ name: "accepts" })
+    .derive({ as: "global" }, ({ headers }) => {
+      const accept = new Accepts({ headers });
+
+      return {
+        /** Return the first accepted charset.
+         * When used as property acts the same as `charsets`.
+         *
+         * @param charsets {string[]} The charsets to accept.
+         * @returns {string[] | string | false} The first accepted charset or false if nothing is accepted.
+         * @deprecated Do not use this header. Browsers omit this header and servers should ignore it.
+         */
+        charset: accept.charset.bind(accept),
+
+        /** Return the charsets that the request accepts, in the order of the client's preference (most preferred first).
+         * Can be used as both property and method.
+         *
+         * @returns {string[]} The charsets that the request accepts, in the order of the client's preference (most preferred first).
+         * @deprecated Do not use this header. Browsers omit this header and servers should ignore it.
+         */
+        charsets: accept.charsets.bind(accept),
+
+        /** Return the first accepted encoding.
+         * If nothing in encodings is accepted, then false is returned.
+         * When used as property acts the same as `encodings`.
+         *
+         * @param encodings {string[]} The encodings to accept.
+         * @returns {string[] | string | false} The first accepted encoding or false if nothing is accepted.
+         */
+        encoding: accept.encoding.bind(accept),
+
+        /** Return the encodings that the request accepts,
+         * in the order of the client's preference (most preferred first).
+         * Can be used as both property and method.
+         *
+         * @returns {string[]} The encodings that the request accepts, in the order of the client's preference (most preferred first).
+         */
+        encodings: accept.encodings.bind(accept),
+
+        /** Return the first accepted language.
+         * If nothing in languages is accepted, then false is returned.
+         * When used as property acts the same as `languages`.
+         *
+         * @param languages {string[]} The languages to accept.
+         * @returns {string[] | string | false} Return the first accepted language. If nothing in languages is accepted, then false is returned.
+         */
+        language: accept.language.bind(accept),
+
+        /** Return the languages that the request accepts,
+         * in the order of the client's preference (most preferred first).
+         * Can be used as both property and method.
+         *
+         * @returns {string[]} Return the languages that the request accepts, in the order of the client's preference (most preferred first).
+         */
+        languages: accept.languages.bind(accept),
+
+        /** Return the first accepted type.
+         * If nothing in types is accepted, then false is returned.
+         * When used as property acts the same as `types`.
+         *
+         * @param types {string[]} The types to accept.
+         * @returns {string[]} The first accepted type.
+         *  It is returned as the same text as what appears in the types array.
+         *  If nothing in types is accepted, then false is returned.
+         */
+        type: accept.type.bind(accept),
+
+        /** Return the types that the request accepts, in the order of the client's preference (most preferred first).
+         * Can be used as both property and method.
+         *
+         * @returns {string[]} The types that the request accepts, in the order of the client's preference (most preferred first).
+         */
+        types: accept.types.bind(accept),
+      };
+    })
+    .macro(({ onBeforeHandle }) => ({
+      /** Check that the client accepts the specified types.
+       * If not, return 406.
+       *
+       * @param types {string[]} The types to accept
+       */
+      types(types: string[]) {
+        onBeforeHandle({ insert: "before" }, ({ type, error }) => {
+          if (type && !type(types)) {
+            return error(406, "Not Acceptable");
+          }
+        });
+      },
+    }));
+}
diff --git a/tsconfig.dts.json b/tsconfig.dts.json
new file mode 100644
index 0000000..f56e2ed
--- /dev/null
+++ b/tsconfig.dts.json
@@ -0,0 +1,24 @@
+{
+  "compilerOptions": {
+    "preserveSymlinks": true,
+    "target": "ES2021",
+    "lib": [
+      "ESNext"
+    ],
+    "resolveJsonModule": true,
+    "declaration": true,
+    "emitDeclarationOnly": true,
+    "outDir": "./dist",
+    "allowSyntheticDefaultImports": true,
+    "esModuleInterop": true,
+    "forceConsistentCasingInFileNames": true,
+    "strict": true,
+    "skipLibCheck": true
+  },
+  "exclude": [
+    "node_modules",
+    "test",
+    "dist",
+    "build.ts"
+  ]
+}
diff --git a/tsconfig.json b/tsconfig.json
new file mode 100644
index 0000000..238655f
--- /dev/null
+++ b/tsconfig.json
@@ -0,0 +1,27 @@
+{
+  "compilerOptions": {
+    // Enable latest features
+    "lib": ["ESNext", "DOM"],
+    "target": "ESNext",
+    "module": "ESNext",
+    "moduleDetection": "force",
+    "jsx": "react-jsx",
+    "allowJs": true,
+
+    // Bundler mode
+    "moduleResolution": "bundler",
+    "allowImportingTsExtensions": true,
+    "verbatimModuleSyntax": true,
+    "noEmit": true,
+
+    // Best practices
+    "strict": true,
+    "skipLibCheck": true,
+    "noFallthroughCasesInSwitch": true,
+
+    // Some stricter flags (disabled by default)
+    "noUnusedLocals": false,
+    "noUnusedParameters": false,
+    "noPropertyAccessFromIndexSignature": false
+  }
+}