vercel/fun

Health v2 · maintenance only

Adoption not part of the score

1013 stars · 44 forks observed · 2026-09-03

What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-30, confidence not recorded

A local runtime for developing and invoking AWS Lambda-style serverless functions on your own machine, exposing a programmatic API (@vercel/fun) that emulates the Lambda execution environment. It supports Node.js and Python runtimes, spawning and freezing function processes locally without sandboxing.

Use cases

• run aws lambda functions locally
• test serverless functions without deploying
• emulate lambda runtime in local development
• invoke lambda handlers programmatically from node.js
• develop serverless functions with hot reloading

When to choose

• you want to invoke AWS Lambda-style functions locally during development
• you need a programmatic API to spawn and manage lambda-like function processes
• you're building tooling that emulates the Lambda execution environment

When to avoid

• you need full sandboxing or security isolation identical to real Lambda
• you rely on hard-coded Lambda paths like /var/task or /opt
• you need runtimes beyond Node.js and Python, such as Go or .NET
• you want a full production serverless platform rather than a dev tool

Facets

library · maturity maintenance

serverless http-server developer-tools testing developer-tools cloud-computing backend apis cross-platform aws-lambda local-development serverless-runtime lambda-emulation typescript nodejs macos linux

Member repositories

For agents

markdown · JSON · MCP: product_card(name="vercel/fun")