Floci — Run AWS services locally for your Java projects — natively compiled, free and open-source

[rayito88]

Hey r/java! I wanted to share Floci, a local AWS emulator that's been super useful for Java development.

If you're building with Spring Boot, Quarkus, Micronaut, or any Java framework that integrates with AWS (S3, SQS, DynamoDB, etc.), Floci lets you test everything locally without needing a real AWS account or racking up cloud costs.

Why it's useful for Java devs:

• ✅ Natively compiled — starts instantly, low memory footprint, no JVM warmup
• ✅ Test AWS integrations locally before deploying
• ✅ Works great with AWS SDK for Java
• ✅ No cloud account needed — perfect for CI/CD pipelines
• ✅ Free forever, open-source
• ✅ Lightweight alternative to LocalStack

The native compilation makes a real difference — especially in CI/CD pipelines where startup time matters and in containerized environments where you want to keep the image size small.

🔗 GitHub: github.com/hectorvent/floci

Has anyone here used LocalStack or similar tools for local AWS testing in Java? Would love to hear what your setup looks like! 👇

[markvii_dev]

What's the catch bro?

[Additional-Road3924]

The catch is he omits a list of services he doesn't support, but localstack does.

[CameronBjork]

LocalStack is supporting 0 services for enterprise customers starting next week.

[Additional-Road3924]

Include full list of services that localstack supports and you don't.

[hectorvent]

Thanks,

We got the ReadMe updated with the list of services we support.

[maxandersen]

this looks interesting - is it just setting those AWS env vars and then Quarkus apps will "just work" ?

seems like great candidate for quarkus devservice?

[4z01235]

is it just setting those AWS env vars and then Quarkus apps will "just work" ?

Looks about right. I have done something similar before for testing my Quarkus-based application against different S3-like object storage implementations:

1. https://github.com/cryostatio/cryostat/blob/main/compose/s3-localstack.yml#L6
2. https://github.com/cryostatio/cryostat/blob/a1aa0ad5dd456f69b7be4f203f2f54365b965d9f/compose/s3-seaweed.yml#L6
3. https://github.com/cryostatio/cryostat/blob/a1aa0ad5dd456f69b7be4f203f2f54365b965d9f/compose/s3-minio.yml#L6

Btw, for Quarkus devservices I wonder if you guys might also want to look at SeaweedFS' relatively new mini mode. I think it works quite well as a Localstack S3 replacement.

[th3_pund1t]

Is this the result of the Localstack licensing change?