Native Binaries · Neon Functions · neondatabase/agent-skills · Skills Docs

Native Binaries · Neon Functions · neondatabase/agent-skills · Skills Docs

The binary is	Use
An npm package backed by a Node-API addon (`sharp`, most `@napi-rs/*` packages)	`externalPackages`
A file your own build step produces: a `.node` addon, a `.so`, a `.wasm`, model weights	`bundler: "none"` or a custom `bundler`
A standalone executable you spawn (`ffmpeg`, a Go or Rust CLI)	A custom `bundler` or `"none"`, plus a copy to `/run` at startup

// neon.ts
import { defineConfig } from "@neon/config/v1";

export default defineConfig({
  functions: {
    resize: {
      name: "Resize",
      source: "./src/resize.ts",
      externalPackages: ["sharp"],
    },
  },
});

// neon.ts
import { readFile } from "node:fs/promises";
import { build } from "esbuild";
import { defineConfig } from "@neon/config/v1";

export default defineConfig({
  functions: {
    transcode: {
      name: "Transcode",
      source: "./src/transcode.ts",
      bundler: async (fn) => {
        const out = await build({
          entryPoints: [fn.source],
          bundle: true,
          platform: "node",
          format: "esm",
          write: false,
          outfile: "index.mjs",
          // CommonJS dependencies call require(); ESM output has none in scope.
          banner: {
            js: "import{createRequire}from'module';const require=createRequire(import.meta.url);",
          },
        });
        return {
          "index.mjs": out.outputFiles[0].contents,
          "bin/ffmpeg": new Uint8Array(
            await readFile(new URL("./vendor/linux-arm64/ffmpeg", import.meta.url)),
          ),
        };
      },
    },
  },
});

// src/transcode.ts
import { execFile } from "node:child_process";
import { chmod, copyFile, mkdir } from "node:fs/promises";
import { promisify } from "node:util";

const run = promisify(execFile);

let ffmpeg: Promise<string> | undefined;
function ffmpegPath(): Promise<string> {
  if (process.env.FFMPEG_PATH) return Promise.resolve(process.env.FFMPEG_PATH);
  ffmpeg ??= (async () => {
    await mkdir("/run/bin", { recursive: true });
    await copyFile(new URL("./bin/ffmpeg", import.meta.url), "/run/bin/ffmpeg");
    await chmod("/run/bin/ffmpeg", 0o755);
    return "/run/bin/ffmpeg";
  })();
  return ffmpeg;
}

export default {
  async fetch() {
    const { stdout } = await run(await ffmpegPath(), ["-version"]);
    return new Response(stdout);
  },
};