We built a free, open-source alternative to LocalStack — and it supports EMR for free

LocalStack is great software. But over time, more and more services moved behind a paid Pro tier — including EMR, EC2, Cognito, and others. For teams running CI/CD pipelines or local dev environments, the cost adds up fast.

So we built MiniStack. The best alternative to LocalStack. .

MiniStack is a pure-Python AWS emulator that runs on a single port (4566), starts in under 2 seconds, and requires zero configuration. No Docker daemon required for core services. MIT licensed, no account needed.

What's supported today:

| Category | Services |

|---|---|

| Storage | S3 (path + virtual-hosted style), DynamoDB |

| Messaging | SQS, SNS, Kinesis, Firehose, EventBridge |

| Compute | Lambda (real Docker containers), ECS, EC2 |

| Data | EMR, Glue, Athena (DuckDB-backed) |

| Database | RDS, ElastiCache |

| Auth | IAM, STS, Cognito (User Pools + Identity Pools) |

| API | API Gateway v1 + v2 |

| Ops | CloudWatch, CloudWatch Logs, Secrets Manager, SSM, SES, Step Functions, Route53 |https://ministack.orghttps://github.com/nahuel990/ministack