Related issues
While there are discussions in the community regarding Bun compatibility (such as oven-sh/bun#8549), there does not appear to be an official tracking issue in firebase-functions for native Bun runtime support for Gen 1/2 Cloud Functions and the local emulator suite.
[REQUIRED] Test case
A package.json for a project attempting to declare Bun as the primary engine:
{
"scripts": {
"build": "bun run build:ts",
"build:ts": "tsc",
"serve": "firebase emulators:start --only functions",
"deploy": "firebase deploy --only functions"
},
"engines": {
"bun": "1.x"
},
"main": "lib/index.js",
"dependencies": {
"firebase-admin": "...",
"firebase-functions": "..."
},
"devDependencies": {
"typescript": "..."
}
}[REQUIRED] Expected behavior
Local Emulator: The emulator suite should respect the declared package manager and runtime environment, executing the function code natively via Bun. This would allow for native TypeScript execution without strictly requiring a tsc build step, alongside significantly faster startup times. Currently, the emulator defaults to spinning up a Node.js process.
Deployment: The Firebase CLI should recognize bun as a valid runtime engine for functions. Because Gen 2 functions are built on top of Cloud Run, the CLI should seamlessly package the function into a container equipped with Bun.
Related issues
While there are discussions in the community regarding Bun compatibility (such as oven-sh/bun#8549), there does not appear to be an official tracking issue in
firebase-functionsfor native Bun runtime support for Gen 1/2 Cloud Functions and the local emulator suite.[REQUIRED] Test case
A
package.jsonfor a project attempting to declare Bun as the primary engine:{ "scripts": { "build": "bun run build:ts", "build:ts": "tsc", "serve": "firebase emulators:start --only functions", "deploy": "firebase deploy --only functions" }, "engines": { "bun": "1.x" }, "main": "lib/index.js", "dependencies": { "firebase-admin": "...", "firebase-functions": "..." }, "devDependencies": { "typescript": "..." } }[REQUIRED] Expected behavior
Local Emulator: The emulator suite should respect the declared package manager and runtime environment, executing the function code natively via Bun. This would allow for native TypeScript execution without strictly requiring a
tscbuild step, alongside significantly faster startup times. Currently, the emulator defaults to spinning up a Node.js process.Deployment: The Firebase CLI should recognize
bunas a valid runtime engine for functions. Because Gen 2 functions are built on top of Cloud Run, the CLI should seamlessly package the function into a container equipped with Bun.