MinIO

MinIO is a high-performance, S3-compatible object storage server you run on your own hardware. If your application already talks to Amazon S3, it can talk to MinIO with no code changes; you point the endpoint at your own server instead of AWS.

The core use case is giving applications a scalable file store without vendor lock-in or per-GB cloud costs. Backups, application uploads, ML training datasets, media archives: anything that would normally land in an S3 bucket can live on MinIO instead. Encryption at rest, versioning, lifecycle policies, and bucket replication all behave exactly as they do on AWS S3.

MinIO also performs well. It regularly benchmarks faster than AWS S3 for high-throughput workloads, which matters when moving large datasets between services on the same network.

The Community Edition is free and open-source under AGPL. For production deployments, running it as a distributed cluster across multiple nodes gives you erasure coding and high availability. Single-node setups work fine for development and lower-traffic production use.

One licensing point worth knowing: if you use MinIO inside a proprietary SaaS product without releasing your source code, you need a commercial license. For most self-hosters and internal use cases this does not apply, but it is worth reading before building a product on top of it.