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infection/mutator
=================

Mutator interface to implement custom mutators (mutation operators) for Infection

0.4.1(1y ago)86.7M—4%21BSD-3-ClausePHPCI failing

Since May 14Pushed 1y ago2 watchersCompare

[ Source](https://github.com/infection/mutator)[ Packagist](https://packagist.org/packages/infection/mutator)[ GitHub Sponsors](https://github.com/infection)[ Fund](https://opencollective.com/infection)[ RSS](/packages/infection-mutator/feed)WikiDiscussions master Synced 1mo ago

READMEChangelog (4)Dependencies (2)Versions (5)Used By (1)

Mutator interface for Infection
===============================

[](#mutator-interface-for-infection)

This is a repository for `Mutator` interface to implement custom mutators (mutation operators).

[![infection-mutator](./docs/infection-mutator.png)](./docs/infection-mutator.png)

### Installation

[](#installation)

```
composer require --dev infection/mutator
```

### Infection - Mutation Testing Framework

[](#infection---mutation-testing-framework)

Please read documentation here: [infection.github.io](http://infection.github.io)

- Twitter: [@infection\_php](http://twitter.com/infection_php)
- Mastodon: [@infection\_php](https://mastodon.social/@infection_php)
- Discord:
- [Playground](https://infection-php.dev/) - try it right in your browser!

###  Health Score

40

—

FairBetter than 88% of packages

Maintenance48

Moderate activity, may be stable

Popularity52

Moderate usage in the ecosystem

Community15

Small or concentrated contributor base

Maturity34

Early-stage or recently created project

 Bus Factor1

Top contributor holds 92.9% of commits — single point of failure

How is this calculated?**Maintenance (25%)** — Last commit recency, latest release date, and issue-to-star ratio. Uses a 2-year decay window.

**Popularity (30%)** — Total and monthly downloads, GitHub stars, and forks. Logarithmic scaling prevents top-heavy scores.

**Community (15%)** — Contributors, dependents, forks, watchers, and maintainers. Measures real ecosystem engagement.

**Maturity (30%)** — Project age, version count, PHP version support, and release stability.

###  Release Activity

Cadence

Every ~116 days

Total

4

Last Release

385d ago

### Community

Maintainers

![](https://www.gravatar.com/avatar/a0196ce472ed16a55b72aa7f9f9956bc6e68fa519abf975caffc9fcb5fa320df?d=identicon)[borN\_free](/maintainers/borN_free)

---

Top Contributors

[![maks-rafalko](https://avatars.githubusercontent.com/u/3725595?v=4)](https://github.com/maks-rafalko "maks-rafalko (13 commits)")[![savinmikhail](https://avatars.githubusercontent.com/u/99592925?v=4)](https://github.com/savinmikhail "savinmikhail (1 commits)")

###  Code Quality

TestsPHPUnit

### Embed Badge

![Health badge](/badges/infection-mutator/health.svg)

```
[![Health](https://phpackages.com/badges/infection-mutator/health.svg)](https://phpackages.com/packages/infection-mutator)
```

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