FEATURESMZPixel-arcade workflow, real engineering

Level up your test suite.

MutantZero is built around one idea: mutation testing should feel like a product — fast, smart, and focused.

L1AI Intelligence

MutantZero treats your code like a world with rules — not a pile of syntax. It classifies function intent and predicts mutant survival to cut wasted compute.

Cloud pricing →

Archetype Classification

6 types

Every function gets classified. High-value archetypes get more mutations, DTOs get skipped.

Algorithm
Math-heavy, loop-intensive logic
Sorting, searching, calculations
High
IO Bound
Async operations, network/DB calls
API clients, data fetching
High
Transformer
Data mapping, string manipulation
Formatters, parsers, serializers
Medium
State Mutator
Side effects, state updates
Event handlers, cache writers
High
Guard
Validation, permission checks
Input validators, auth guards
Critical
DTO
Pure data carriers
Plain objects, data containers
Skip

Predictive Mutation Testing

PMT

A second AI layer predicts which mutants will survive — and skips them entirely.

22
Feature dimensions
Analyzed per mutation point
50%
Time reduction
No loss in effectiveness
Real-time survival prediction before execution
Configurable thresholds (speed vs coverage)
Self-learning system improves with usage
Works across all supported languages
L2Performance

Choose speed, isolation, and repeatability — without changing how you think about runs.

Install →
Sequential
Baseline
Isolation: None
Best for: Small projects, debugging
Parallel (Local)
Fast
Isolation: File-copy
Best for: Most projects
Parallel (Docker)
Moderate
Isolation: Complete
Best for: CI/CD, untrusted code
Intelligent caching
Content-hash incremental caching
Automatic invalidation when code changes
Cross-run persistence for faster reruns
Smart cache management UI
Worker pool optimization
Configurable parallelism (1–N workers)
Memory-aware scheduling
Automatic load balancing
Graceful failure handling
L3Mutation Operators

150+ mutation rules across 14 categories — language-aware operators for JS/TS.

Arithmetic & Math

42
Arithmetic+ → −, × → ÷
Unary++ → −−, sign flip
Assignment+= → −=, compound
Bitwise& → |, shifts

Logic & Control

40
Relational> → >=, === → !==
Logical&& → ||, !x → x
Conditionaltrue → false, flip
Blockstatement removal

Data & Types

52
String.trim() → .trimStart()
Array.push() → .pop()
Objectproperty, spread
Nullish?? → ||, ?. chains

Advanced

18
Regexquantifiers, patterns
Methodcall replacement
152
Total operators
Across all categories
JS / TS SpecificEnhanced

JSX mutations, async/await handling, optional chaining (?.), nullish coalescing (??), and TypeScript-aware type guards.

L4Languages

Multi-language support powered by tree-sitter for fast, resilient AST parsing.

JavaScript
Stable
tree-sitter-javascript
TypeScript
Stable
tree-sitter-typescript
Why tree-sitter?
Incremental parsing for speed
Error recovery for partial code analysis
Syntax highlighting accuracy in results
Consistent cross-language API
Roadmap

Python, Go, Rust, Kotlin — coming after the core lanes are fully mastered.

Want a language sooner?
Open an issue and tell us your stack.
L5Analysis & Reporting

Don't just get a score — get a map: hotspots, coverage context, and git-aware focus.

Hotspot analysis
Complexity metrics (cyclomatic, cognitive)
Change frequency (git churn)
Risk scoring from multiple factors
Historical trends across runs
Coverage integration
LCOV format support
Covered-lines-only mutation mode
Coverage-weighted risk assessment
Visual coverage overlay in results
Git-aware testing
Diff-based filtering for PR validation
Branch comparison support
Commit range targeting
File path filtering via gitignore patterns
L6Desktop App

A modern React desktop experience that makes surviving mutants easy to understand, not just easy to generate.

Get started →
Lab
Run mutation tests with real-time progress
Quarantine
Review survived mutants in detail
Archaeologist
Explore code with mutation overlays
Oracle
AI-powered insights and recommendations
Crew
Team collaboration (coming soon)
Settings
Configure everything in one place
Real-time feedback
Live progress during mutation runs
Socket-based updates for instant feedback
Expandable logs and diagnostics
Actionable error suggestions
Visualization
Mutation score trends over time
Archetype distribution charts
Operator effectiveness heatmaps
Function-level drill-down
TIPStart with local runs, then offload to Cloud when you need speed.