Dynoxide MCP server

Dynoxide

A DynamoDB emulator in Rust, backed by SQLite. Runs as an HTTP server or an MCP server for coding agents, embeds into Rust and iOS applications as a library, and compiles to WebAssembly for the browser.

The crates.io badge above shows the crate version, which covers the Rust library alone. Everything you install rather than depend on carries a separate product version: the binary, the npm packages, the container images, the browser engine and the Action. That is the number dynoxide --version prints and the one to quote in a bug report. Why there are two.

Why Dynoxide?

I built Dynoxide because DynamoDB Local is slow, heavy, and can't embed. It needs a JVM, and the typical Docker-based setups adds <!-- prose:ddblocalcoldstart -->2–3 seconds<!-- /bench --> of cold-start, <!-- prose:ddblocalidlememory -->~205 MB<!-- /bench --> of memory at idle, and a <!-- prose:ddblocalimagesize -->~225MB<!-- /bench --> Docker image (<!-- prose:ddblocalimagesize_disk -->~473 MB<!-- /bench --> on disk) before you've done anything useful. If you're running integration tests, that's Docker starting, the JVM warming up, and your pipeline waiting.

Dynoxide is a native binary. It starts in milliseconds, idles at <!-- prose:dynoxideidlememory -->~5.3 MB<!-- /bench -->, and ships as a <!-- prose:dynoxidebinarysize -->~3 MB<!-- /bench --> download. Point any DynamoDB SDK at it and your tests just work.

For Rust projects, there's also an embedded mode - direct API calls via Database::memory() with no HTTP layer at all. Each test gets an isolated in-memory database with zero startup cost. And because it compiles to a native library with no runtime dependencies, it runs on platforms where DynamoDB Local can't, including iOS.

Performance

Local Development (Apple Silicon)

CI (GitHub Actions)

Numbers from ubuntu-latest (<!-- prose:cirunnerhardware -->4-core Intel(R) Xeon(R) 6973P-C, 16GB RAM<!-- /bench -->). Commit <!-- bench:cicommitlink_root -->49c6338<!-- /bench -->.

Shortened. The full README is on GitHub.