characterization-tests

refactoring tool that aims at making it easy to create characterization tests

A harness for writing Golden Master tests in Java, painlessly.

TWIST is an open framework for Li-ion cell characterization based on Python and Raspberry Pi

An extension of JUnit5 that enables approval testing for Java-based software.

An example java project created for my blog post "Golden master testing aka Characterization test: a powerful tool to win your fight against legacy code"

Gated maintainer for your Python repos: tools find problems, an LLM patches them, merged only if tests cover the change

Regression testing system for Apertium language data and translators

Claude Code skills for repository audits and documentation: verify README and docs claims against the code, run audits where every finding cites a resolvable path:line, write AGENTS.md and CLAUDE.md with only what code cannot say, check a README's first screen, rank test gaps. Tested standard-library scripts, no network.

FastApproval is an open source assertion/verification library to aid testing

legadox — a camada de seguranca do metodo Expx: skill que endurece o trabalho de IA em projetos legados para Claude Code e OpenCode. Calcula raio de impacto por evidencia, congela o comportamento atual com testes de caracterizacao, limita o diff e exige aprovacao humana onde o estrago seria real.

Simple High school management backend example showcasing 4-tier architecture pattern. Handles class enrollment, student assignments, and grading with clear seperation between layers.

Baseline test and approve your serializable outputs

Executable Java strangler migration: legacy characterization tests, shadow comparison, deterministic canary routing and rollback.

Companion TypeScript demo for tracing, characterizing, refactoring, and changing an unfamiliar booking system.

Executable specification of the LaserGRBL core (Python): white-box, protocol and golden tests for the FreeKerf Rust rewrite

Behavior-preserving refactoring case study with characterization tests and a clearer domain model.

Excel/Access modernisation lab: source-controlled VBA, object inventories, characterisation tests, generated SDLC docs and .NET migration spikes.

Run your program once. Get real, proof-carrying tests.

AI-powered characterization test generator for Python — MCP server + CLI. Pin legacy code behavior in pytest before you refactor.