Node.js Can Now Be Packaged as an EXE—Evan You Shows It Starts Faster Than Bun

What Is Node.js SEA?

SEA stands for Single Executable Applications . Traditionally, a Node.js program requires the runtime to be installed, then npm install and node app.js to run. SEA bundles your script together with the V8 engine into a single binary that runs by double‑clicking, without any environment dependencies.

Distribute CLI tools : team members can run a scaffold without installing Node.

Deliver client applications : ship a single clean file to customers.

CI/CD pipelines : reduce build‑environment dependency management.

Edge/embedded : deploy Node apps on resource‑constrained devices.

Unlike Go or Rust, Node.js must bundle the entire V8 engine and your scripts, which makes the implementation technically distinct.

From "Usable" to "Polished": Three Years of Development

2023‑early (v19.7.0): SEA landed but required a cumbersome manual process using an external tool postject to inject a blob into a Node binary, with many low‑level steps and poor documentation.

2023‑2025 (v20 → v24): Iterations added JSON config, asset bundling, V8 code cache, etc., but still relied on postject and only supported CommonJS, leaving ESM projects unable to use SEA.

2026‑01‑26 (v25.5.0): Joyee Cheung moved the injection logic into the Node core, integrating the LIEF library to handle ELF, PE, and Mach‑O formats. SEA can now be built with a single command: node --build-sea sea-config.json Later on 2026‑02‑18, PR #61813 added ESM entry‑point support, completing the feature set.

Why ESM Support Matters

By 2026 most new projects use ESM ( import/export) instead of CommonJS ( require). Previously SEA only accepted CJS entry points, forcing developers to downgrade or abandon SEA. PR #61813 introduced a "mainFormat": "module" field in the SEA config, enabling ESM parsing and features such as import, dynamic import(), top‑level await, and meta‑information ( import.meta.url, import.meta.filename, import.meta.dirname).

Current limitations: ESM mode does not yet support V8 code cache ( useCodeCache) or startup snapshots ( useSnapshot), and import.meta.resolve awaits VFS support.

tsdown --exe: One Command Does It All

With the --build-sea flag, the workflow is simplified, but TypeScript developers still need to compile to JavaScript before building the executable. The upcoming tsdown version (based on Rolldown) will embed a --exe flag to perform "TS compile + bundle + SEA generation" in a single step.

Evan You benchmarked the result: a Node.js SEA built with Rolldown starts faster than bun --compile. However, Bun 1.3.9 later introduced bytecode optimizations that made its startup about 25 % faster than Node.js SEA with code cache.

Hands‑On: Build a Node.js SEA in Five Minutes

Step 1 – Create hello.js:

// hello.js
console.log(`Hello, ${process.argv[2] || 'World'}!`);

Step 2 – Create sea-config.json:

{
  "main": "hello.js",
  "output": "hello"
}

Step 3 – Generate the executable: node --build-sea sea-config.json Step 4 – Run it:

./hello Node.js
# Output: Hello, Node.js!

On macOS you may need to sign the binary: codesign --sign - hello For ESM projects, adjust the config to include:

{
  "main": "app.mjs",
  "output": "my-app",
  "mainFormat": "module"
}

With TypeScript + tsdown, the command simplifies to:

tsdown --exe

The Contributor Behind SEA: Joyee Cheung

Joyee Cheung, a core Node.js contributor, drove the migration of the SEA build process into the core, integrated the LIEF library for cross‑platform binaries, and implemented ESM entry support (PR #61813). She recounts that after early contributors left, development stalled until she revived the project during a vacation, read LIEF documentation, and submitted the pivotal PR.

This story illustrates how critical features in large open‑source projects often rely on the persistence of a few dedicated engineers.