roto

An AWS simulator written in Rust: a from-scratch rewrite of moto's server mode. One static binary, AWS wire-protocol compatible, persistent by default (SQLite + real-filesystem S3).

Status: under active development. See STATUS.md for current coverage and PLAN.md for the roadmap.

Documentation: The roto book (sources).

uv tool install roto-aws
roto-server --port 5070                      # persistent: ./roto-data ; add --ephemeral for in-memory
aws --endpoint-url http://localhost:5070 sts get-caller-identity
scripts/run-moto-tests.sh test_sts              # moto's own tests, run against roto

Lambda functions can execute local commands or POST events to an HTTP API. Configure bindings with --lambda-executors; see the runnable example and contracts. S3 bucket notifications invoke those same executors.

Documentation

python3 -m venv .venv-docs
.venv-docs/bin/python -m pip install -r requirements-docs.txt
.venv-docs/bin/zensical serve

GitHub Actions builds the book on pull requests and deploys main to GitHub Pages. Set the repository's Pages source to GitHub Actions. See the documentation guide for details.

Python package releases

Install with uv tool install roto-aws; the package provides the roto-server command. Upgrade with uv tool upgrade roto-aws. For development from source, run cargo run -p roto-server -- --port 5070.

Push a Cargo-compatible version tag such as v0.0.1 to trigger .github/workflows/release.yml. The shared workflow sets the workspace version from the tag, builds Linux x64/ARM64, Windows x64, macOS Intel/ARM64 wheels and a source distribution, then the local publishing job uploads them to PyPI. The shared components are pinned to a commit in vivainio/actions.

Before the first release, create the GitHub environment pypi and configure a PyPI Trusted Publisher (or pending publisher for a new project) with:

• Project: roto-aws
• Owner: vivainio
• Repository: roto
• Workflow filename: release.yml
• Environment: pypi

Release tags should point to commits that pass the existing CI checks.

Build locally with uvx maturin build --release --locked --out dist or uvx maturin sdist --out dist.

To retry uploading already-built distributions, run the release workflow manually and provide the original release run ID in artifact-run-id. This skips rebuilding and publishes that run's artifacts. Verify the chosen run belongs to the release you intend to publish.

License

MIT. See LICENSE.