AWS Lambda Runtime for Deno

A lightweight, zero-dependency Deno library for AWS Lambda that implements the AWS Lambda Runtime API.

Designed for use with deno compile to create binaries deployable to AWS Lambda using the provided.al2023 runtime.

While aws-lambda-web-adapter is officially recommended by Deno for web applications, it requires an HTTP server. This project enables you to create general-purpose Lambda functions in Deno for services like EventBridge, SQS, and other non-HTTP event sources without the overhead of an HTTP server.

Installation

import { start } from "jsr:@atty303/aws-lambda-runtime";

Quick Start

Create a simple Lambda function:

import { Context, Handler, start } from "jsr:@atty303/aws-lambda-runtime";

interface Event {
  name: string;
}

const handler: Handler<Event> = async (event, context) => {
  return {
    statusCode: 200,
    body: JSON.stringify({
      message: `Hello, ${event.name}!`,
      requestId: context.awsRequestId,
    }),
  };
};

start(handler);

API Reference

Types

Handler<A>

type Handler<A> = (
  event: A,
  context: Context,
) => unknown | Promise<unknown>;

The main handler function type that processes Lambda events.

Context

type Context = {
  awsRequestId: string;
  invokedFunctionArn?: string;
  deadlineMs: number;
  functionName?: string;
  functionVersion?: string;
  memoryLimitInMB?: string;
  logGroupName?: string;
  logStreamName?: string;
  clientContext?: unknown;
  identity?: unknown;
  getRemainingTimeInMillis(): number;
};

The Lambda context object containing runtime information.

Functions

start<A>(handler: Handler<A>): Promise<never>

Starts the Lambda runtime with the provided handler function. This function runs indefinitely, processing incoming Lambda invocations.

Parameters:

• handler: The function to handle Lambda events

Example:

import { start } from "jsr:@atty303/aws-lambda-runtime";

const myHandler = async (event, context) => {
  // Your handler logic here
  return { success: true };
};

start(myHandler);

Deployment

Using AWS SAM

Create a template.yaml:

AWSTemplateFormatVersion: "2010-09-09"
Transform: AWS::Serverless-2016-10-31

Resources:
  MyFunction:
    Type: AWS::Serverless::Function
    Metadata:
      BuildMethod: makefile
    Properties:
      CodeUri: .
      Handler: bootstrap
      Runtime: provided.al2023
      Architectures:
        - arm64
      Environment:
        Variables:
          DENO_DIR: /tmp

Create a Makefile:

.PHONY: build-MyFunction

build-MyFunction:
	deno compile -A --target aarch64-unknown-linux-gnu -o $(ARTIFACTS_DIR)/bootstrap src/main.ts

Build and deploy with SAM:

sam deploy

Using Terraform

You can use terraform-aws-modules/lambda/aws to build and deploy your function:

module "my_lambda" {
  source  = "terraform-aws-modules/lambda/aws"
  version = "~> 8"

  function_name         = "my-function"
  handler               = "bootstrap"
  runtime               = "provided.al2023"
  architectures         = ["arm64"]
  environment_variables = {
    DENO_DIR = "/tmp"
  }

  source_path = [{
    path = "function_dir"
    commands = [
      "set -e",
      "deno compile -A --target aarch64-unknown-linux-gnu --output dist/bootstrap src/main.ts",
      ":zip dist",
    ]
  }]
}

Development

Prerequisites

• mise installed

mise install
hk install --mise