LocalStack Has a Free API: Run AWS Services Locally Without an AWS Account

#localstack #aws #testing #docker

LocalStack emulates 80+ AWS services on your laptop. Test Lambda, S3, DynamoDB, SQS, SNS, and more — completely offline, completely free. Your existing AWS SDK code works without changes.

Why LocalStack?

80+ AWS services — S3, Lambda, DynamoDB, SQS, SNS, API Gateway...
No AWS account needed — fully local, no cloud costs
Same API — use standard AWS SDKs and CLI
Fast feedback — test in seconds, not minutes
CI-friendly — Docker container, works in any CI

Quick Start

# Docker
docker run -d --name localstack \
  -p 4566:4566 -p 4510-4559:4510-4559 \
  localstack/localstack

# Or via pip
pip install localstack
localstack start

# Or Docker Compose

AWS CLI Against LocalStack

# Configure endpoint
export AWS_ENDPOINT_URL=http://localhost:4566
export AWS_DEFAULT_REGION=us-east-1
export AWS_ACCESS_KEY_ID=test
export AWS_SECRET_ACCESS_KEY=test

# S3
aws --endpoint-url=$AWS_ENDPOINT_URL s3 mb s3://my-bucket
aws --endpoint-url=$AWS_ENDPOINT_URL s3 cp file.txt s3://my-bucket/
aws --endpoint-url=$AWS_ENDPOINT_URL s3 ls s3://my-bucket/

# DynamoDB
aws --endpoint-url=$AWS_ENDPOINT_URL dynamodb create-table \
  --table-name users \
  --key-schema AttributeName=id,KeyType=HASH \
  --attribute-definitions AttributeName=id,AttributeType=S \
  --billing-mode PAY_PER_REQUEST

aws --endpoint-url=$AWS_ENDPOINT_URL dynamodb put-item \
  --table-name users \
  --item '{"id": {"S": "1"}, "name": {"S": "Alice"}}'

# SQS
aws --endpoint-url=$AWS_ENDPOINT_URL sqs create-queue --queue-name my-queue
aws --endpoint-url=$AWS_ENDPOINT_URL sqs send-message \
  --queue-url http://localhost:4566/000000000000/my-queue \
  --message-body '{"event": "user_signup"}'

# Lambda
aws --endpoint-url=$AWS_ENDPOINT_URL lambda create-function \
  --function-name hello \
  --runtime python3.12 \
  --handler handler.lambda_handler \
  --zip-file fileb://function.zip \
  --role arn:aws:iam::000000000000:role/lambda-role

aws --endpoint-url=$AWS_ENDPOINT_URL lambda invoke \
  --function-name hello \
  --payload '{"name": "World"}' output.json

Python (boto3 — No Code Changes!)

import boto3

# Just change the endpoint
s3 = boto3.client('s3', endpoint_url='http://localhost:4566')
dynamodb = boto3.resource('dynamodb', endpoint_url='http://localhost:4566')
sqs = boto3.client('sqs', endpoint_url='http://localhost:4566')

# Use exactly like real AWS
s3.create_bucket(Bucket='my-bucket')
s3.put_object(Bucket='my-bucket', Key='data.json', Body='{"hello": "world"}')

# DynamoDB
table = dynamodb.Table('users')
table.put_item(Item={'id': '1', 'name': 'Alice', 'email': 'alice@example.com'})
result = table.get_item(Key={'id': '1'})
print(result['Item'])  # {'id': '1', 'name': 'Alice', 'email': 'alice@example.com'}

Docker Compose

version: '3'
services:
  localstack:
    image: localstack/localstack
    ports:
      - "4566:4566"
    environment:
      - SERVICES=s3,sqs,dynamodb,lambda
      - DEBUG=1
    volumes:
      - "./init-aws.sh:/etc/localstack/init/ready.d/init-aws.sh"

  app:
    build: .
    environment:
      - AWS_ENDPOINT_URL=http://localstack:4566
      - AWS_DEFAULT_REGION=us-east-1
      - AWS_ACCESS_KEY_ID=test
      - AWS_SECRET_ACCESS_KEY=test
    depends_on:
      - localstack

Free vs Pro

Feature	Free	Pro
Core services	S3, SQS, DynamoDB, Lambda, SNS, etc.	All 80+
API Gateway	REST API	REST + HTTP + WebSocket
IAM	Basic	Full policy enforcement
Persistence	No	Yes
Cloud Pods	No	Yes

Resources

Need AWS testing or data automation? Check my Apify actors or email spinov001@gmail.com.

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