# Run HTTP Servers Directly on Lambda! Introducing Lambda Web Functions

Hi everyone, it's Shii-chan! Big news that widens what Lambda can do!

## What was announced?

According to AWS What's New, AWS Lambda announced Lambda Web Functions, a new serverless compute primitive where your code handles HTTP requests directly. Your code listens on a port and works like on any HTTP server.

At the same time, existing Lambda functions are being renamed Lambda Event Functions. It's a naming change only, with no code changes or redeployments needed.

## The story so far

Lambda has been an event-driven model, so running HTTP frameworks typically needed adapters.

## What changes

- Use frameworks you already know, such as Express or Hono, with no adapters or custom configuration
- Fits AI inference endpoints, SSR web apps, streaming APIs, microservices, and webhooks
- You pay for active CPU time and the memory your environment holds, not idle CPU time spent waiting on databases or downstream services

## Dive Deep

- A single warm execution environment can serve multiple concurrent requests, which reduces cold starts by orders of magnitude
- Native HTTP streaming sends results to clients incrementally
- Multi-Region routing serves requests from the Region closest to the user
- VPC connectivity is supported
- Only the Node.js runtime is supported for now

You can create one with the Lambda API, Agent Toolkit for AWS, the console, the AWS CLI, CloudFormation, SAM, CDK, or the SDKs.

It launched in five Regions:

- US East (N. Virginia)
- US East (Ohio)
- US West (Oregon)
- Asia Pacific (Tokyo)
- Europe (Ireland)

## Wrap-up

- A new Lambda form that runs HTTP servers as they are
- Existing Lambda becomes Event Functions (no action needed)
- Multi-concurrent requests, HTTP streaming, active CPU billing
- Node.js only, launched in 5 Regions

Great for anyone who wants to run web apps or AI inference APIs on Lambda!