rustest 0.16.0

Rust powered pytest-compatible runner

Rustest is a Rust-powered pytest-compatible test runner delivering 8.5× average speedup with familiar pytest syntax and zero setup.

📚 Full Documentation | Getting Started | Migration Guide

🚀 Try It Now

Run your existing pytest tests with rustest — no code changes required:

pip install rustest
rustest --pytest-compat tests/

See the speedup immediately, then migrate to native rustest for full features.

Why Rustest?

• 🚀 8.5× average speedup over pytest (up to 19× on large suites)
• 🧪 pytest-compatible — Run existing tests with --pytest-compat
• ✅ Familiar API — Same @fixture, @parametrize, @mark decorators
• 🔄 Built-in async & mocking — No pytest-asyncio or pytest-mock plugins needed
• 🐛 Clear error messages — Vitest-style output with Expected/Received diffs
• 📝 Markdown testing — Test code blocks in documentation
• 🛠️ Rich fixtures — tmp_path, monkeypatch, mocker, capsys, caplog, cache, and more

Performance

Rustest delivers consistent speedups across test suites of all sizes:

Test Count	pytest	rustest	Speedup
20	0.45s	0.12s	3.8×
500	1.21s	0.15s	8.3×
5,000	7.81s	0.40s	19.4×

Expected speedups: 3-4× for small suites, 5-8× for medium suites, 11-19× for large suites.

📊 Full Performance Analysis →

Installation

pip install rustest
# or
uv add rustest

Python 3.10-3.14 supported. 📖 Installation Guide →

Quick Start

Write a test in test_example.py:

from rustest import fixture, parametrize, mark, raises

@fixture
def numbers():
    return [1, 2, 3, 4, 5]

def test_sum(numbers):
    assert sum(numbers) == 15

@parametrize("value,expected", [(2, 4), (3, 9)])
def test_square(value, expected):
    assert value ** 2 == expected

@mark.asyncio
async def test_async():
    result = 42
    assert result == 42

def test_exception():
    with raises(ZeroDivisionError):
        1 / 0

Run your tests:

rustest                      # Run all tests
rustest tests/               # Run specific directory
rustest -k "test_sum"        # Filter by name
rustest -m "slow"            # Filter by mark
rustest --lf                 # Rerun last failed
rustest -x                   # Exit on first failure

📖 Full Documentation →

Learn More

• Getting Started — Complete quickstart guide
• Migration from pytest — 5-minute migration guide
• User Guide — Fixtures, parametrization, marks, assertions
• API Reference — Complete API documentation

Contributing

Contributions welcome! See the Development Guide for setup instructions.

License

MIT License. See LICENSE for details.