Add bun-npm package to publish and install Bun via npm

25 files changed, 897 insertions, 0 deletions

diff --git a/packages/bun-npm/.gitignore b/packages/bun-npm/.gitignore
new file mode 100644
index 000000000..39931eeba
--- /dev/null
+++ b/packages/bun-npm/.gitignore
@@ -0,0 +1,5 @@
+.DS_Store
+.env
+node_modules
+/npm/**/bin
+/npm/**/*.js
diff --git a/packages/bun-npm/README.md b/packages/bun-npm/README.md
new file mode 100644
index 000000000..4556f0f4d
--- /dev/null
+++ b/packages/bun-npm/README.md
@@ -0,0 +1,15 @@
+# bun-npm
+
+Scripts that allow Bun to be installed with `npm install`.
+
+### Running
+
+```sh
+bun run npm # build assets for the latest release
+bun run npm -- <release> # build assets for the provided release
+bun run npm -- <release> [dry-run|publish] # build and publish assets to npm
+```
+
+### Credits
+
+- [esbuild](https://github.com/evanw/esbuild), for its npm scripts which this was largely based off of.
diff --git a/packages/bun-npm/bun.lockb b/packages/bun-npm/bun.lockb
new file mode 100755
index 000000000..c87d1c9cf
--- /dev/null
+++ b/packages/bun-npm/bun.lockb
diff --git a/packages/bun-npm/npm/@oven/bun-darwin-aarch64/README.md b/packages/bun-npm/npm/@oven/bun-darwin-aarch64/README.md
new file mode 100644
index 000000000..3b03fdd9f
--- /dev/null
+++ b/packages/bun-npm/npm/@oven/bun-darwin-aarch64/README.md
@@ -0,0 +1,3 @@
+# Bun
+
+This is the macOS arm64 binary for Bun, a fast all-in-one JavaScript runtime. https://bun.sh
diff --git a/packages/bun-npm/npm/@oven/bun-darwin-aarch64/package.json b/packages/bun-npm/npm/@oven/bun-darwin-aarch64/package.json
new file mode 100644
index 000000000..e4dd34f7c
--- /dev/null
+++ b/packages/bun-npm/npm/@oven/bun-darwin-aarch64/package.json
@@ -0,0 +1,16 @@
+{
+  "name": "@oven/bun-darwin-aarch64",
+  "version": "0.1.7",
+  "description": "This is the macOS arm64 binary for Bun, a fast all-in-one JavaScript runtime.",
+  "homepage": "https://bun.sh",
+  "bugs": "https://github.com/oven-sh/issues",
+  "license": "MIT",
+  "repository": "https://github.com/oven-sh/bun",
+  "preferUnplugged": true,
+  "os": [
+    "darwin"
+  ],
+  "cpu": [
+    "arm64"
+  ]
+}
\ No newline at end of file
diff --git a/packages/bun-npm/npm/@oven/bun-darwin-x64-baseline/README.md b/packages/bun-npm/npm/@oven/bun-darwin-x64-baseline/README.md
new file mode 100644
index 000000000..e451cccfe
--- /dev/null
+++ b/packages/bun-npm/npm/@oven/bun-darwin-x64-baseline/README.md
@@ -0,0 +1,5 @@
+# Bun
+
+This is the macOS x64 binary for Bun, a fast all-in-one JavaScript runtime. https://bun.sh
+
+_Note: "Baseline" builds are for machines that do not support [AVX2](https://en.wikipedia.org/wiki/Advanced_Vector_Extensions) instructions._
diff --git a/packages/bun-npm/npm/@oven/bun-darwin-x64-baseline/package.json b/packages/bun-npm/npm/@oven/bun-darwin-x64-baseline/package.json
new file mode 100644
index 000000000..16af70345
--- /dev/null
+++ b/packages/bun-npm/npm/@oven/bun-darwin-x64-baseline/package.json
@@ -0,0 +1,16 @@
+{
+  "name": "@oven/bun-darwin-x64-baseline",
+  "version": "0.1.7",
+  "description": "This is the macOS x64 binary for Bun, a fast all-in-one JavaScript runtime.",
+  "homepage": "https://bun.sh",
+  "bugs": "https://github.com/oven-sh/issues",
+  "license": "MIT",
+  "repository": "https://github.com/oven-sh/bun",
+  "preferUnplugged": true,
+  "os": [
+    "darwin"
+  ],
+  "cpu": [
+    "x64"
+  ]
+}
\ No newline at end of file
diff --git a/packages/bun-npm/npm/@oven/bun-darwin-x64/README.md b/packages/bun-npm/npm/@oven/bun-darwin-x64/README.md
new file mode 100644
index 000000000..be73fd7a2
--- /dev/null
+++ b/packages/bun-npm/npm/@oven/bun-darwin-x64/README.md
@@ -0,0 +1,3 @@
+# Bun
+
+This is the macOS x64 binary for Bun, a fast all-in-one JavaScript runtime. https://bun.sh
diff --git a/packages/bun-npm/npm/@oven/bun-darwin-x64/package.json b/packages/bun-npm/npm/@oven/bun-darwin-x64/package.json
new file mode 100644
index 000000000..3ae5c4c31
--- /dev/null
+++ b/packages/bun-npm/npm/@oven/bun-darwin-x64/package.json
@@ -0,0 +1,16 @@
+{
+  "name": "@oven/bun-darwin-x64",
+  "version": "0.1.7",
+  "description": "This is the macOS x64 binary for Bun, a fast all-in-one JavaScript runtime.",
+  "homepage": "https://bun.sh",
+  "bugs": "https://github.com/oven-sh/issues",
+  "license": "MIT",
+  "repository": "https://github.com/oven-sh/bun",
+  "preferUnplugged": true,
+  "os": [
+    "darwin"
+  ],
+  "cpu": [
+    "x64"
+  ]
+}
\ No newline at end of file
diff --git a/packages/bun-npm/npm/@oven/bun-linux-aarch64/README.md b/packages/bun-npm/npm/@oven/bun-linux-aarch64/README.md
new file mode 100644
index 000000000..e727d8008
--- /dev/null
+++ b/packages/bun-npm/npm/@oven/bun-linux-aarch64/README.md
@@ -0,0 +1,3 @@
+# Bun
+
+This is the Linux arm64 binary for Bun, a fast all-in-one JavaScript runtime. https://bun.sh
diff --git a/packages/bun-npm/npm/@oven/bun-linux-aarch64/package.json b/packages/bun-npm/npm/@oven/bun-linux-aarch64/package.json
new file mode 100644
index 000000000..138c870c6
--- /dev/null
+++ b/packages/bun-npm/npm/@oven/bun-linux-aarch64/package.json
@@ -0,0 +1,16 @@
+{
+  "name": "@oven/bun-linux-aarch64",
+  "version": "0.1.7",
+  "description": "This is the Linux arm64 binary for Bun, a fast all-in-one JavaScript runtime.",
+  "homepage": "https://bun.sh",
+  "bugs": "https://github.com/oven-sh/issues",
+  "license": "MIT",
+  "repository": "https://github.com/oven-sh/bun",
+  "preferUnplugged": true,
+  "os": [
+    "linux"
+  ],
+  "cpu": [
+    "arm64"
+  ]
+}
\ No newline at end of file
diff --git a/packages/bun-npm/npm/@oven/bun-linux-x64-baseline/README.md b/packages/bun-npm/npm/@oven/bun-linux-x64-baseline/README.md
new file mode 100644
index 000000000..6b2ce0fcf
--- /dev/null
+++ b/packages/bun-npm/npm/@oven/bun-linux-x64-baseline/README.md
@@ -0,0 +1,5 @@
+# Bun
+
+This is the Linux x64 binary for Bun, a fast all-in-one JavaScript runtime. https://bun.sh
+
+_Note: "Baseline" builds are for machines that do not support [AVX2](https://en.wikipedia.org/wiki/Advanced_Vector_Extensions) instructions._
diff --git a/packages/bun-npm/npm/@oven/bun-linux-x64-baseline/package.json b/packages/bun-npm/npm/@oven/bun-linux-x64-baseline/package.json
new file mode 100644
index 000000000..89500a8e5
--- /dev/null
+++ b/packages/bun-npm/npm/@oven/bun-linux-x64-baseline/package.json
@@ -0,0 +1,16 @@
+{
+  "name": "@oven/bun-linux-x64-baseline",
+  "version": "0.1.7",
+  "description": "This is the Linux x64 binary for Bun, a fast all-in-one JavaScript runtime.",
+  "homepage": "https://bun.sh",
+  "bugs": "https://github.com/oven-sh/issues",
+  "license": "MIT",
+  "repository": "https://github.com/oven-sh/bun",
+  "preferUnplugged": true,
+  "os": [
+    "linux"
+  ],
+  "cpu": [
+    "x64"
+  ]
+}
\ No newline at end of file
diff --git a/packages/bun-npm/npm/@oven/bun-linux-x64/README.md b/packages/bun-npm/npm/@oven/bun-linux-x64/README.md
new file mode 100644
index 000000000..e0fac1347
--- /dev/null
+++ b/packages/bun-npm/npm/@oven/bun-linux-x64/README.md
@@ -0,0 +1,3 @@
+# Bun
+
+This is the Linux x64 binary for Bun, a fast all-in-one JavaScript runtime. https://bun.sh
diff --git a/packages/bun-npm/npm/@oven/bun-linux-x64/package.json b/packages/bun-npm/npm/@oven/bun-linux-x64/package.json
new file mode 100644
index 000000000..c4332e3e0
--- /dev/null
+++ b/packages/bun-npm/npm/@oven/bun-linux-x64/package.json
@@ -0,0 +1,16 @@
+{
+  "name": "@oven/bun-linux-x64",
+  "version": "0.1.7",
+  "description": "This is the Linux x64 binary for Bun, a fast all-in-one JavaScript runtime.",
+  "homepage": "https://bun.sh",
+  "bugs": "https://github.com/oven-sh/issues",
+  "license": "MIT",
+  "repository": "https://github.com/oven-sh/bun",
+  "preferUnplugged": true,
+  "os": [
+    "linux"
+  ],
+  "cpu": [
+    "x64"
+  ]
+}
\ No newline at end of file
diff --git a/packages/bun-npm/npm/bun/README.md b/packages/bun-npm/npm/bun/README.md
new file mode 100644
index 000000000..cf4c3c759
--- /dev/null
+++ b/packages/bun-npm/npm/bun/README.md
@@ -0,0 +1,31 @@
+# Bun
+
+Bun is a fast all-in-one JavaScript runtime. https://bun.sh
+
+### Install
+
+```sh
+npm install -g bun
+```
+
+### Upgrade
+
+```sh
+bun upgrade
+```
+
+### Supported Platforms
+
+- [macOS, arm64 (Apple Silicon)](https://www.npmjs.com/package/@oven/bun-darwin-aarch64)
+- [macOS, x64](<(https://www.npmjs.com/package/@oven/bun-darwin-x64)>)
+- [macOS, x64 (without AVX2 instructions)](https://www.npmjs.com/package/@oven/bun-darwin-x64-baseline)
+- [Linux, arm64](https://www.npmjs.com/package/@oven/bun-linux-aarch64)
+- [Linux, x64](https://www.npmjs.com/package/@oven/bun-linux-x64)
+- [Linux, x64 (without AVX2 instructions)](https://www.npmjs.com/package/@oven/bun-linux-x64-baseline)
+- [Windows (using Windows Subsystem for Linux, aka. "WSL")](https://relatablecode.com/how-to-set-up-bun-on-a-windows-machine)
+
+### Future Platforms
+
+- [Windows](https://github.com/oven-sh/bun/issues/43)
+- Unix-like variants such as FreeBSD, OpenBSD, etc.
+- Android and iOS
diff --git a/packages/bun-npm/npm/bun/package.json b/packages/bun-npm/npm/bun/package.json
new file mode 100644
index 000000000..b88097d74
--- /dev/null
+++ b/packages/bun-npm/npm/bun/package.json
@@ -0,0 +1,41 @@
+{
+  "name": "bun",
+  "version": "0.1.7",
+  "description": "Bun is a fast all-in-one JavaScript runtime.",
+  "keywords": [
+    "bun",
+    "bun.js",
+    "node",
+    "node.js",
+    "runtime",
+    "bundler",
+    "transpiler",
+    "typescript"
+  ],
+  "homepage": "https://bun.sh",
+  "bugs": "https://github.com/oven-sh/issues",
+  "license": "MIT",
+  "bin": {
+    "bun": "bin/bun"
+  },
+  "repository": "https://github.com/oven-sh/bun",
+  "scripts": {
+    "postinstall": "node install.js"
+  },
+  "optionalDependencies": {
+    "@oven/bun-darwin-aarch64": "0.1.7",
+    "@oven/bun-darwin-x64": "0.1.7",
+    "@oven/bun-darwin-x64-baseline": "0.1.7",
+    "@oven/bun-linux-aarch64": "0.1.7",
+    "@oven/bun-linux-x64": "0.1.7",
+    "@oven/bun-linux-x64-baseline": "0.1.7"
+  },
+  "os": [
+    "darwin",
+    "linux"
+  ],
+  "cpu": [
+    "arm64",
+    "x64"
+  ]
+}
\ No newline at end of file
diff --git a/packages/bun-npm/package.json b/packages/bun-npm/package.json
new file mode 100644
index 000000000..33de39c3c
--- /dev/null
+++ b/packages/bun-npm/package.json
@@ -0,0 +1,15 @@
+{
+  "private": true,
+  "dependencies": {},
+  "devDependencies": {
+    "@octokit/types": "^8.1.1",
+    "bun-types": "^0.4.0",
+    "prettier": "^2.8.2",
+    "esbuild": "^0.17.3",
+    "jszip": "^3.10.1"
+  },
+  "scripts": {
+    "format": "prettier --write src scripts",
+    "npm": "bun scripts/npm-build.ts"
+  }
+}
diff --git a/packages/bun-npm/scripts/npm-build.ts b/packages/bun-npm/scripts/npm-build.ts
new file mode 100644
index 000000000..95178d77e
--- /dev/null
+++ b/packages/bun-npm/scripts/npm-build.ts
@@ -0,0 +1,190 @@
+import type { Endpoints } from "@octokit/types";
+import { fetch, spawn } from "../src/util";
+import type { JSZipObject } from "jszip";
+import { loadAsync } from "jszip";
+import { join } from "node:path";
+import { chmod, read, write } from "../src/util";
+import type { BuildOptions } from "esbuild";
+import { buildSync, formatMessagesSync } from "esbuild";
+import type { Platform } from "../src/platform";
+import { platforms } from "../src/platform";
+
+const tag = process.argv[2];
+const release = await getRelease(tag);
+const version = release.tag_name.replace("bun-v", "");
+const npmPackage = "bun";
+const npmOwner = "@oven";
+
+await buildBasePackage();
+for (const platform of platforms) {
+  await buildPackage(platform);
+}
+const publish = process.argv[3] === "publish";
+const dryRun = process.argv[3] === "dry-run";
+if (publish || dryRun) {
+  const npmPackages = platforms.map(({ bin }) => `${npmOwner}/${bin}`);
+  npmPackages.push(npmPackage);
+  for (const npmPackage of npmPackages) {
+    publishPackage(npmPackage, dryRun);
+  }
+}
+
+async function buildBasePackage() {
+  const done = log("Building:", `${npmPackage}@${version}`);
+  const cwd = join("npm", npmPackage);
+  const define = {
+    npmVersion: `"${version}"`,
+    npmPackage: `"${npmPackage}"`,
+    npmOwner: `"${npmOwner}"`,
+  };
+  buildJs(join("scripts", "npm-postinstall.ts"), join(cwd, "install.js"), {
+    define,
+  });
+  buildJs(join("scripts", "npm-exec.ts"), join(cwd, "bin", "bun"), {
+    define,
+    banner: {
+      js: "#!/usr/bin/env node",
+    },
+  });
+  const os = [...new Set(platforms.map(({ os }) => os))];
+  const cpu = [...new Set(platforms.map(({ arch }) => arch))];
+  patchJson(join(cwd, "package.json"), {
+    name: npmPackage,
+    version,
+    scripts: {
+      postinstall: "node install.js",
+    },
+    optionalDependencies: Object.fromEntries(
+      platforms.map(({ bin }) => [`${npmOwner}/${bin}`, version]),
+    ),
+    bin: {
+      bun: "bin/bun",
+    },
+    os,
+    cpu,
+  });
+  done();
+}
+
+async function buildPackage({ bin, exe, os, arch }: Platform): Promise<void> {
+  const npmPackage = `${npmOwner}/${bin}`;
+  const done = log("Building:", `${npmPackage}@${version}`);
+  const asset = release.assets.find(({ name }) => name === `${bin}.zip`);
+  if (!asset) {
+    throw new Error(`No asset found: ${bin}`);
+  }
+  const bun = await extractFromZip(asset.browser_download_url, `${bin}/bun`);
+  const cwd = join("npm", npmPackage);
+  write(join(cwd, exe), await bun.async("arraybuffer"));
+  chmod(join(cwd, exe), 0o755);
+  patchJson(
+    join(cwd, "package.json"),
+    {
+      name: npmPackage,
+      version,
+      preferUnplugged: true,
+      os: [os],
+      cpu: [arch],
+    }
+  );
+  done();
+}
+
+function publishPackage(name: string, dryRun?: boolean): void {
+  const done = log(dryRun ? "Dry-run Publishing:" : "Publishing:", name);
+  const { exitCode, stdout, stderr } = spawn(
+    "npm",
+    [
+      "publish",
+      "--access",
+      "public",
+      "--tag",
+      version === "canary" ? "canary" : "latest",
+      ...(dryRun ? ["--dry-run"] : []),
+    ],
+    {
+      cwd: join("npm", name),
+    },
+  );
+  if (exitCode === 0) {
+    done();
+    return;
+  }
+  throw new Error(stdout || stderr);
+}
+
+async function extractFromZip(
+  url: string,
+  filename: string,
+): Promise<JSZipObject> {
+  const response = await fetch(url);
+  const buffer = await response.arrayBuffer();
+  const zip = await loadAsync(buffer);
+  for (const [name, file] of Object.entries(zip.files)) {
+    if (!file.dir && name.startsWith(filename)) {
+      return file;
+    }
+  }
+  console.warn("Found files:", Object.keys(zip.files));
+  throw new Error(`File not found: ${filename}`);
+}
+
+async function getRelease(
+  version?: string | null,
+): Promise<
+  Endpoints["GET /repos/{owner}/{repo}/releases/latest"]["response"]["data"]
+> {
+  const tag = version
+    ? version === "canary" || version.startsWith("bun-v")
+      ? version
+      : `bun-v${version}`
+    : null;
+  const response = await fetch(
+    tag
+      ? `https://api.github.com/repos/oven-sh/bun/releases/tags/${tag}`
+      : `https://api.github.com/repos/oven-sh/bun/releases/latest`,
+  );
+  return response.json();
+}
+
+function patchJson(path: string, patch: object): void {
+  let value;
+  try {
+    const existing = JSON.parse(read(path));
+    value = {
+      ...existing,
+      ...patch,
+    };
+  } catch {
+    value = patch;
+  }
+  write(path, JSON.stringify(value, undefined, 2));
+}
+
+function buildJs(src: string, dst: string, options: BuildOptions = {}): void {
+  const { errors } = buildSync({
+    bundle: true,
+    treeShaking: true,
+    keepNames: true,
+    minifySyntax: true,
+    pure: ["console.debug"],
+    platform: "node",
+    target: "es6",
+    format: "cjs",
+    entryPoints: [src],
+    outfile: dst,
+    ...options,
+  });
+  if (errors?.length) {
+    const messages = formatMessagesSync(errors, { kind: "error" });
+    throw new Error(messages.join("\n"));
+  }
+}
+
+function log(...args: any[]): () => void {
+  console.write(Bun.inspect(...args));
+  const start = Date.now();
+  return () => {
+    console.write(` [${(Date.now() - start).toFixed()} ms]\n`);
+  };
+}
diff --git a/packages/bun-npm/scripts/npm-exec.ts b/packages/bun-npm/scripts/npm-exec.ts
new file mode 100644
index 000000000..3937247cb
--- /dev/null
+++ b/packages/bun-npm/scripts/npm-exec.ts
@@ -0,0 +1,13 @@
+import { importBun } from "../src/install";
+import { execFileSync } from "child_process";
+
+importBun()
+  .then((bun) => {
+    return execFileSync(bun, process.argv.slice(2), {
+      stdio: "inherit",
+    });
+  })
+  .catch((error) => {
+    console.error(error);
+    process.exit(1);
+  });
diff --git a/packages/bun-npm/scripts/npm-postinstall.ts b/packages/bun-npm/scripts/npm-postinstall.ts
new file mode 100644
index 000000000..c22f2c669
--- /dev/null
+++ b/packages/bun-npm/scripts/npm-postinstall.ts
@@ -0,0 +1,10 @@
+import { importBun, optimizeBun } from "../src/install";
+
+importBun()
+  .then((path) => {
+    optimizeBun(path);
+  })
+  .catch((error) => {
+    console.error(error);
+    process.exit(1);
+  });
diff --git a/packages/bun-npm/src/install.ts b/packages/bun-npm/src/install.ts
new file mode 100644
index 000000000..fbf7a76bf
--- /dev/null
+++ b/packages/bun-npm/src/install.ts
@@ -0,0 +1,151 @@
+import { fetch, chmod, join, rename, rm, tmp, write, spawn } from "./util";
+import { unzipSync } from "zlib";
+import type { Platform } from "./platform";
+import { os, arch, supportedPlatforms } from "./platform";
+
+declare const npmVersion: string;
+declare const npmPackage: string;
+declare const npmOwner: string;
+
+export async function importBun(): Promise<string> {
+  if (!supportedPlatforms.length) {
+    throw new Error(`Unsupported platform: ${os} ${arch}`);
+  }
+  for (const platform of supportedPlatforms) {
+    try {
+      return await requireBun(platform);
+    } catch (error) {
+      console.debug("requireBun failed", error);
+    }
+  }
+  throw new Error(`Failed to install package "${npmPackage}"`);
+}
+
+async function requireBun(platform: Platform): Promise<string> {
+  const npmPackage = `${npmOwner}/${platform.bin}`;
+  function resolveBun() {
+    const exe = require.resolve(join(npmPackage, platform.exe));
+    const { exitCode, stderr, stdout } = spawn(exe, ["--version"]);
+    if (exitCode === 0) {
+      return exe;
+    }
+    throw new Error(stderr || stdout);
+  }
+  try {
+    return resolveBun();
+  } catch (error) {
+    console.debug("resolveBun failed", error);
+    console.error(
+      `Failed to find package "${npmPackage}".`,
+      `You may have used the "--no-optional" flag when running "npm install".`,
+    );
+  }
+  const cwd = join("node_modules", npmPackage);
+  try {
+    installBun(platform, cwd);
+  } catch (error) {
+    console.debug("installBun failed", error);
+    console.error(
+      `Failed to install package "${npmPackage}" using "npm install".`,
+      error,
+    );
+    try {
+      await downloadBun(platform, cwd);
+    } catch (error) {
+      console.debug("downloadBun failed", error);
+      console.error(
+        `Failed to download package "${npmPackage}" from "registry.npmjs.org".`,
+        error,
+      );
+    }
+  }
+  return resolveBun();
+}
+
+function installBun(platform: Platform, dst: string): void {
+  const npmPackage = `${npmOwner}/${platform.bin}`;
+  const cwd = tmp();
+  try {
+    write(join(cwd, "package.json"), "{}");
+    const { exitCode } = spawn(
+      "npm",
+      [
+        "install",
+        "--loglevel=error",
+        "--prefer-offline",
+        "--no-audit",
+        "--progress=false",
+        `${npmPackage}@${npmVersion}`,
+      ],
+      {
+        cwd,
+        stdio: "pipe",
+        env: {
+          ...process.env,
+          npm_config_global: undefined,
+        },
+      },
+    );
+    if (exitCode === 0) {
+      rename(join(cwd, "node_modules", npmPackage), dst);
+    }
+  } finally {
+    try {
+      rm(cwd);
+    } catch (error) {
+      console.debug("rm failed", error);
+      // There is nothing to do if the directory cannot be cleaned up.
+    }
+  }
+}
+
+async function downloadBun(platform: Platform, dst: string): Promise<void> {
+  const response = await fetch(
+    `https://registry.npmjs.org/${npmOwner}/${platform.bin}/-/${platform.bin}-${npmVersion}.tgz`,
+  );
+  const tgz = await response.arrayBuffer();
+  let buffer: Buffer;
+  try {
+    buffer = unzipSync(tgz);
+  } catch (cause) {
+    throw new Error("Invalid gzip data", { cause });
+  }
+  function str(i: number, n: number): string {
+    return String.fromCharCode(...buffer.subarray(i, i + n)).replace(
+      /\0.*$/,
+      "",
+    );
+  }
+  let offset = 0;
+  while (offset < buffer.length) {
+    const name = str(offset, 100).replace("package/", "");
+    const size = parseInt(str(offset + 124, 12), 8);
+    offset += 512;
+    if (!isNaN(size)) {
+      write(join(dst, name), buffer.subarray(offset, offset + size));
+      if (name === platform.exe) {
+        try {
+          chmod(join(dst, name), 0o755);
+        } catch (error) {
+          console.debug("chmod failed", error);
+        }
+      }
+      offset += (size + 511) & ~511;
+    }
+  }
+}
+
+export function optimizeBun(path: string): void {
+  if (os === "win32") {
+    return;
+  }
+  const { npm_config_user_agent } = process.env;
+  if (npm_config_user_agent && /\byarn\//.test(npm_config_user_agent)) {
+    return;
+  }
+  try {
+    rename(path, join(__dirname, "bin", "bun"));
+  } catch (error) {
+    console.debug("optimizeBun failed", error);
+  }
+}
diff --git a/packages/bun-npm/src/platform.ts b/packages/bun-npm/src/platform.ts
new file mode 100644
index 000000000..a01cc3ddc
--- /dev/null
+++ b/packages/bun-npm/src/platform.ts
@@ -0,0 +1,100 @@
+import { read, spawn } from "./util";
+
+export const os = process.platform;
+
+export const arch =
+  os === "darwin" && process.arch === "x64" && isRosetta2()
+    ? "arm64"
+    : process.arch;
+
+export const avx2 =
+  (arch === "x64" && os === "linux" && isLinuxAVX2()) ||
+  (os === "darwin" && isDarwinAVX2());
+
+export type Platform = {
+  os: string;
+  arch: string;
+  avx2?: boolean;
+  bin: string;
+  exe: string;
+};
+
+export const platforms: Platform[] = [
+  {
+    os: "darwin",
+    arch: "arm64",
+    bin: "bun-darwin-aarch64",
+    exe: "bin/bun",
+  },
+  {
+    os: "darwin",
+    arch: "x64",
+    avx2: true,
+    bin: "bun-darwin-x64",
+    exe: "bin/bun",
+  },
+  {
+    os: "darwin",
+    arch: "x64",
+    bin: "bun-darwin-x64-baseline",
+    exe: "bin/bun",
+  },
+  {
+    os: "linux",
+    arch: "arm64",
+    bin: "bun-linux-aarch64",
+    exe: "bin/bun",
+  },
+  {
+    os: "linux",
+    arch: "x64",
+    avx2: true,
+    bin: "bun-linux-x64",
+    exe: "bin/bun",
+  },
+  {
+    os: "linux",
+    arch: "x64",
+    bin: "bun-linux-x64-baseline",
+    exe: "bin/bun",
+  },
+];
+
+export const supportedPlatforms: Platform[] = platforms
+  .filter(
+    (platform) =>
+      platform.os === os && platform.arch === arch && (!platform.avx2 || avx2),
+  )
+  .sort((a, b) => (a.avx2 === b.avx2 ? 0 : a.avx2 ? -1 : 1));
+
+function isLinuxAVX2(): boolean {
+  try {
+    return read("/proc/cpuinfo").includes("avx2");
+  } catch (error) {
+    console.debug("isLinuxAVX2 failed", error);
+    return false;
+  }
+}
+
+function isDarwinAVX2(): boolean {
+  try {
+    const { exitCode, stdout } = spawn("sysctl", ["-n", "machdep.cpu"]);
+    return exitCode === 0 && stdout.includes("AVX2");
+  } catch (error) {
+    console.debug("isDarwinAVX2 failed", error);
+    return false;
+  }
+}
+
+function isRosetta2(): boolean {
+  try {
+    const { exitCode, stdout } = spawn("sysctl", [
+      "-n",
+      "sysctl.proc_translated",
+    ]);
+    return exitCode === 0 && stdout.includes("1");
+  } catch (error) {
+    console.debug("isRosetta2 failed", error);
+    return false;
+  }
+}
diff --git a/packages/bun-npm/src/util.ts b/packages/bun-npm/src/util.ts
new file mode 100644
index 000000000..c36bda2b7
--- /dev/null
+++ b/packages/bun-npm/src/util.ts
@@ -0,0 +1,191 @@
+import fs from "fs";
+import path, { dirname } from "path";
+import { tmpdir } from "os";
+import child_process from "child_process";
+
+if (process.env["DEBUG"] !== "1") {
+  console.debug = () => {};
+}
+
+export function join(...paths: (string | string[])[]): string {
+  return path.join(...paths.flat(2));
+}
+
+export function tmp(): string {
+  const path = fs.mkdtempSync(join(tmpdir(), "bun-"));
+  console.debug("tmp", path);
+  return path;
+}
+
+export function rm(path: string): void {
+  console.debug("rm", path);
+  try {
+    fs.rmSync(path, { recursive: true });
+    return;
+  } catch (error) {
+    console.debug("rmSync failed", error);
+    // Did not exist before Node.js v14.
+    // Attempt again with older, slower implementation.
+  }
+  let stats: fs.Stats;
+  try {
+    stats = fs.lstatSync(path);
+  } catch (error) {
+    console.debug("lstatSync failed", error);
+    // The file was likely deleted, so return early.
+    return;
+  }
+  if (!stats.isDirectory()) {
+    fs.unlinkSync(path);
+    return;
+  }
+  try {
+    fs.rmdirSync(path, { recursive: true });
+    return;
+  } catch (error) {
+    console.debug("rmdirSync failed", error);
+    // Recursive flag did not exist before Node.js X.
+    // Attempt again with older, slower implementation.
+  }
+  for (const filename of fs.readdirSync(path)) {
+    rm(join(path, filename));
+  }
+  fs.rmdirSync(path);
+}
+
+export function rename(path: string, newPath: string): void {
+  console.debug("rename", path, newPath);
+  try {
+    fs.renameSync(path, newPath);
+    return;
+  } catch (error) {
+    console.debug("renameSync failed", error);
+    // If there is an error, delete the new path and try again.
+  }
+  try {
+    rm(newPath);
+  } catch (error) {
+    console.debug("rm failed", error);
+    // The path could have been deleted already.
+  }
+  fs.renameSync(path, newPath);
+}
+
+export function write(
+  path: string,
+  content: string | ArrayBuffer | ArrayBufferView,
+): void {
+  console.debug("write", path);
+  try {
+    fs.writeFileSync(path, content);
+    return;
+  } catch (error) {
+    console.debug("writeFileSync failed", error);
+    // If there is an error, ensure the parent directory
+    // exists and try again.
+    try {
+      fs.mkdirSync(dirname(path), { recursive: true });
+    } catch (error) {
+      console.debug("mkdirSync failed", error);
+      // The directory could have been created already.
+    }
+    fs.writeFileSync(path, content);
+  }
+}
+
+export function read(path: string): string {
+  console.debug("read", path);
+  return fs.readFileSync(path, "utf-8");
+}
+
+export function chmod(path: string, mode: fs.Mode): void {
+  console.debug("chmod", path, mode);
+  fs.chmodSync(path, mode);
+}
+
+export function spawn(
+  cmd: string,
+  args: string[],
+  options: child_process.SpawnOptions = {},
+): {
+  exitCode: number;
+  stdout: string;
+  stderr: string;
+} {
+  console.debug("spawn", [cmd, ...args].join(" "));
+  const { status, stdout, stderr } = child_process.spawnSync(cmd, args, {
+    stdio: "pipe",
+    encoding: "utf-8",
+    ...options,
+  });
+  return {
+    exitCode: status ?? 1,
+    stdout,
+    stderr,
+  };
+}
+
+export type Response = {
+  readonly status: number;
+  arrayBuffer(): Promise<ArrayBuffer>;
+  json<T>(): Promise<T>;
+};
+
+export const fetch = "fetch" in globalThis ? webFetch : nodeFetch;
+
+async function webFetch(url: string, assert?: boolean): Promise<Response> {
+  const response = await globalThis.fetch(url);
+  console.debug("fetch", url, response.status);
+  if (assert !== false && !isOk(response.status)) {
+    throw new Error(`${response.status}: ${url}`);
+  }
+  return response;
+}
+
+async function nodeFetch(url: string, assert?: boolean): Promise<Response> {
+  const { get } = await import("node:http");
+  return new Promise((resolve, reject) => {
+    get(url, (response) => {
+      console.debug("get", url, response.statusCode);
+      const status = response.statusCode ?? 501;
+      if (response.headers.location && isRedirect(status)) {
+        return nodeFetch(url).then(resolve, reject);
+      }
+      if (assert !== false && !isOk(status)) {
+        return reject(new Error(`${status}: ${url}`));
+      }
+      const body: Buffer[] = [];
+      response.on("data", (chunk) => {
+        body.push(chunk);
+      });
+      response.on("end", () => {
+        resolve({
+          status,
+          async arrayBuffer() {
+            return Buffer.concat(body).buffer as ArrayBuffer;
+          },
+          async json() {
+            const text = Buffer.concat(body).toString("utf-8");
+            return JSON.parse(text);
+          },
+        });
+      });
+    }).on("error", reject);
+  });
+}
+
+function isOk(status: number): boolean {
+  return status === 200;
+}
+
+function isRedirect(status: number): boolean {
+  switch (status) {
+    case 301: // Moved Permanently
+    case 308: // Permanent Redirect
+    case 302: // Found
+    case 307: // Temporary Redirect
+    case 303: // See Other
+      return true;
+  }
+  return false;
+}
diff --git a/packages/bun-npm/tsconfig.json b/packages/bun-npm/tsconfig.json
new file mode 100644
index 000000000..9272b9920
--- /dev/null
+++ b/packages/bun-npm/tsconfig.json
@@ -0,0 +1,17 @@
+{
+  "compilerOptions": {
+    "lib": ["esnext"],
+    "module": "esnext",
+    "target": "esnext",
+    "moduleResolution": "node",
+    "types": ["bun-types"],
+    "esModuleInterop": true,
+    "allowJs": true,
+    "strict": true,
+    "resolveJsonModule": true
+  },
+  "include": [
+    "src",
+    "scripts"
+  ]
+}