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On the recordRead 8 Oct 202620 facts
mutmut
On the record
- Applying mutants
- Users can write a mutant to disk from the browse interface or with the mutmut apply command.mutmut.readthedocs.io · read 7 Oct 2026
- CI output
- It can export CI statistics and create mutation score badge data for a Shields endpoint.mutmut.readthedocs.io · read 8 Oct 2026
- Configuration
- Configuration is supported in setup.cfg or pyproject.toml, including source paths and pytest test selection arguments.mutmut.readthedocs.io · read 8 Oct 2026
- Coverage and type checking
- Optional filters can use coverage.py to select covered lines and mypy or pyrefly to filter invalid mutants.mutmut.readthedocs.io · read 8 Oct 2026
- Coverage integration
- mutmut can use coverage.py to filter mutations to covered lines when configured.mutmut.readthedocs.io · read 7 Oct 2026
- Distribution
- The PyPI listing shows mutmut version 3.8.0, released September 12, 2026.pypi.org · read 7 Oct 2026
- Incremental runs
- It remembers completed work so mutation testing can continue incrementally.mutmut.readthedocs.io · read 8 Oct 2026
- Interface
- It provides an interactive terminal based interface for browsing mutants.mutmut.readthedocs.io · read 8 Oct 2026
- License
- The package is distributed under the BSD-3-Clause license.pypi.org · read 8 Oct 2026
- Mutation scope
- The documentation says mutmut 3 and later mutate code inside functions, while mutmut 2 has a different execution model for code outside functions.mutmut.readthedocs.io · read 7 Oct 2026
- Operating system requirement
- mutmut requires a system with fork support; Windows users must run it inside WSL.mutmut.readthedocs.io · read 7 Oct 2026
- Parallel execution
- The project lists parallel and fast execution as features.mutmut.readthedocs.io · read 8 Oct 2026
- Purpose
- mutmut is a mutation testing system for Python focused on ease of use.mutmut.readthedocs.io · read 8 Oct 2026
- Pytest
- A basic run invokes pytest on tests in a tests or test folder.mutmut.readthedocs.io · read 8 Oct 2026
- Python requirement
- The package requires Python 3.10 or later.pypi.org · read 8 Oct 2026
- Security and compliance
- The project repository identifies its license as BSD-3-Clause.github.com · read 7 Oct 2026
- Test selection
- It determines which tests to execute for a mutant to speed up mutation testing.mutmut.readthedocs.io · read 8 Oct 2026
- Type checker integration
- The documentation supports filtering mutants with mypy or pyrefly and says pyright and ty are not currently supported for this purpose.mutmut.readthedocs.io · read 7 Oct 2026
