pytest-rxdist

rxdist is a planned drop-in replacement for pytest-xdist, aiming to make large pytest suites run significantly faster via a Rust-powered execution core, smarter scheduling, and faster inter-process communication (IPC).

The Python package name is pytest-rxdist (import as pytest_rxdist).

Status

This repository currently contains planning and roadmap docs. Implementation work has not started yet.

What it aims to improve (vs pytest-xdist)

• Scheduling efficiency: predictive scheduling using historical runtimes to reduce idle workers
• Lower overhead: a Rust core to orchestrate workers efficiently
• Faster IPC: move beyond Python pickle toward binary / zero-copy options
• Worker reuse: “warm” workers with cached imports (and carefully controlled caching)
• Scales up: from laptop parallelism to multi-machine distributed execution

Planned CLI

pytest -p pytest_rxdist -n auto
pytest --rxdist-scheduler=smart
pytest --rxdist-profile=on

Docs

• Roadmap: ROADMAP.md
• Planning docs
  • planning/pytest_rust_runner_plan.md
  • planning/rxdist_full_idea_doc.md

Repository notes

• planning/ is intentionally ignored (see .gitignore) so you can iterate on internal notes without committing them.