Getting Started

Welcome to Tarn! This guide will help you get up and running in minutes.

Active Development

Tarn is under active development. Expect breaking changes as we finalize the MVP.

Known limitations:

• EventBridge: Scheduled rules only; event patterns are not supported yet
• S3: Path-style only; virtual-hosted style is not supported
• SNS and SQS cross-account resources are not supported

Learn more about what we want to build with Tarn in the project roadmap.

Quick Start

Prerequisites

• Go 1.26+ (for building from source)
• Docker (required for Lambda execution)

Installation

# Build from source
make build && make start

The server will start on http://127.0.0.1:4566

Point Your Tools

Configure the AWS CLI, SDK, or Terraform to use Tarn:

export AWS_ENDPOINT_URL=http://127.0.0.1:4566
export AWS_ACCESS_KEY_ID=test
export AWS_SECRET_ACCESS_KEY=test
export AWS_DEFAULT_REGION=us-east-1

Deploy a Function

Use Tarn commands directly by default. If you prefer AWS-compatible workflows, the AWS CLI tab uses awslocal.

Tarn

tarn lambda create \
  --name hello-tarn \
  --runtime nodejs20.x \
  --handler index.handler \
  --zip ./function.zip

tarn lambda invoke \
  --name hello-tarn \
  --payload '{"hello":"tarn"}'

AWS CLI

awslocal lambda create-function \
  --function-name hello-tarn \
  --runtime nodejs20.x \
  --handler index.handler \
  --role arn:aws:iam::000000000000:role/lambda-role \
  --zip-file fileb://function.zip

awslocal lambda invoke \
  --function-name hello-tarn \
  response.json

First Commands

Tarn

# List Lambda functions
tarn lambda list

AWS CLI

awslocal lambda list-functions

What's Next?

• Services Overview — See what AWS services are supported
• Lambda Guide — Deploy and invoke functions
• Configuration — Customize ports, regions, storage
• Contributing — Help build Tarn