Open-source testing software
1069 open-source libraries, tools and applications tagged testing, ranked by how closely testing is their primary purpose, then by adoption and maintenance health. Each entry links to a page with sources, use cases and when to choose or avoid it.
1069 products, primary matches first, then adoption-weighted; health v2 shown.
| Product | Health v2 | Stars | Maturity |
|---|---|---|---|
| sivchari/kumo Kumo is a lightweight AWS service emulator written in Go that mimics 82 AWS services such as S3, DynamoDB, SQS, and Lambda. It runs as a si… | 82 | 1497 | active |
| openclaw/crabbox Crabbox is a Go CLI and execution control plane that leases remote runners (cloud VMs, SSH hosts, containers, or sandbox providers), syncs … | 78 | 1495 | active |
| osprey-oss/deptry deptry is a command line tool that detects unused, missing, and transitive dependency issues in Python projects by scanning imported module… | 88 | 1494 | active |
| Steep Steep is a static type checker for Ruby based on gradual typing, using RBS signature files and inline annotations. It is distributed as a R… | 97 | 1492 | active |
| Random User Generator The Node.js source code powering randomuser.me, a free API that generates random user data (names, emails, addresses, IDs) for application … | 23 | 1492 | active |
| imanghafoori1/laravel-microscope Laravel Microscope is a PHP/Laravel package that performs smart static checks to find bugs and errors in Laravel codebases, supporting fear… | 67 | 1490 | active |
| Jwuthri/Tracely-ai Tracely is a self-hosted, trace-native CI/CD and observability platform for AI agents. It ingests agent traces over OpenTelemetry, grades t… | 58 | 1490 | active |
| orlangure/gnomock Gnomock is a Go integration and end-to-end testing toolkit that spins up ephemeral Docker containers for application dependencies with prec… | 53 | 1488 | active |
| shuttle-hq/synth Synth is a declarative data generator written in Rust that produces realistic synthetic test data from a version-controllable data model. I… | 23 | 1486 | active |
| callstack/reassure Reassure is a performance testing library for React and React Native that automates performance regression testing. It measures render dura… | 84 | 1484 | active |
| kalessil/phpinspectionsea Php Inspections (EA Extended) is an open-source static code analysis tool distributed as a PhpStorm/IntelliJ IDEA plugin. It detects archit… | 73 | 1483 | active |
| cpputest/cpputest CppUTest is a C/C++ xUnit-style unit testing and mocking framework, written in C++ but usable from both C and C++ projects. It is designed … | 62 | 1483 | stable |
| slevomat/coding-standard A collection of PHP_CodeSniffer sniffs for PHP covering functional safety, dead code detection, and code formatting rules. Many sniffs supp… | 94 | 1480 | active |
| fsouza/fake-gcs-server fake-gcs-server is a Google Cloud Storage emulator that can run as a standalone binary/Docker image or be embedded as a Go library in test … | 96 | 1479 | active |
| robotframework/SeleniumLibrary SeleniumLibrary is a web testing library for Robot Framework that wraps Selenium to enable browser-based test automation with keyword-drive… | 76 | 1474 | active |
| boxed/mutmut mutmut is a mutation testing tool for Python that mutates source code to verify test suite quality. It offers an interactive terminal UI, i… | 84 | 1471 | active |
| taiki-e/cargo-llvm-cov cargo-llvm-cov is a Cargo subcommand that wraps rustc's -C instrument-coverage to generate precise LLVM source-based code coverage reports … | 94 | 1469 | stable |
| pytest-dev/pytest-bdd pytest-bdd is a pytest plugin that implements a subset of the Gherkin language for behavior-driven development (BDD). It lets you write fea… | 75 | 1466 | active |
| pdbpp/pdbpp pdb++ (pdbpp) is a drop-in replacement for Python's built-in pdb debugger that adds features like colorful TAB completion, syntax highlight… | 23 | 1466 | active |
| terraform-compliance/cli terraform-compliance is a lightweight, security-focused BDD test framework for Terraform that enables negative testing of infrastructure-as… | 84 | 1463 | active |
| PyCQA/pyflakes Pyflakes is a fast, passive checker for Python source files that detects errors like undefined names and unused imports by parsing the AST … | 75 | 1461 | active |
| alexmojaki/snoop snoop is a Python debugging library that traces function execution via a decorator, logging which lines ran and how local variables changed… | 70 | 1461 | active |
| ionelmc/pytest-benchmark A pytest plugin that provides a benchmark fixture for measuring code performance within tests. It automatically calibrates test rounds to t… | 82 | 1457 | stable |
| testing-library/react-hooks-testing-library A Testing Library utility for testing React custom hooks by rendering them inside a test harness function component, with utilities like re… | 23 | 5258 | maintenance |
| zipmark/rspec_api_documentation A Ruby gem that generates API documentation automatically from RSpec acceptance specs, primarily for Rails APIs. It produces HTML or JSON o… | 34 | 1451 | active |
| leancodepl/patrol Patrol is a Flutter-first, multiplatform E2E UI testing framework that extends Flutter's integration_test with native platform interactions… | 94 | 1448 | active |
| lycorp-jp/sim-use sim-use is a cross-platform Swift CLI that gives AI agents the ability to observe and act on iOS Simulator and Android emulator/device scre… | 81 | 1448 | active |
| boost-ext/ut UT (μt) is a C++20 micro unit testing framework distributed as a single header or C++20 module. It provides a macro-free, DSL-style API for… | 73 | 1445 | active |
| atoum/atoum atoum is a modern, standalone unit testing framework for PHP, distributed as a single PHAR archive. It offers fluent, natural-language-styl… | 10 | 1441 | active |
| bovigo/vfsStream vfsStream is a PHP stream wrapper that provides a virtual file system in memory, primarily for mocking the real file system in unit tests. … | 23 | 1440 | stable |
| stevepryde/thirtyfour Thirtyfour is a Selenium/WebDriver client library for Rust for automated browser and website UI testing. It supports the W3C WebDriver prot… | 100 | 1439 | active |
| microsoft/waza Waza is a Go CLI from Microsoft for evaluating AI agent skills through structured benchmarks. Users define test cases and validation rules … | 83 | 1424 | active |
| chaijs/chai-as-promised Chai as Promised is a Chai plugin that adds fluent assertions about promises, such as `.should.eventually.equal(...)` and `.should.be.rejec… | 67 | 1417 | stable |
| Dropnation/contract-fuzzer A Python-based fuzzer for Ethereum smart contracts that compiles Solidity sources and executes random sequences of public/external calls to… | 75 | 1413 | active |
| AliSoftware/OHHTTPStubs OHHTTPStubs is an Objective-C/Swift library for stubbing network requests in iOS and macOS apps. It intercepts requests made through Cocoa'… | 23 | 5066 | maintenance |
| helm-unittest/helm-unittest A BDD-style unit test framework for Kubernetes Helm charts, distributed as a Helm plugin that adds a `helm unittest` command to the Helm CL… | 95 | 1403 | active |
| dashbitco/mox Mox is an Elixir library for defining concurrent mocks based on explicit behaviours (contracts). It enforces strict mocking principles so t… | 75 | 1400 | stable |
| kolodny/safetest Safetest is a TypeScript UI testing library that combines Playwright with Jest/Vitest for end-to-end and component testing of web applicati… | 21 | 1400 | active |
| rubycdp/cuprite Cuprite is a pure Ruby headless Chrome/Chromium driver for Capybara that communicates directly via the Chrome DevTools Protocol through Fer… | 83 | 1397 | active |
| dnaeon/go-vcr A Go library inspired by Ruby's VCR that records HTTP interactions to YAML cassettes and replays them in future test runs. It enables fast,… | 83 | 1397 | active |
| shellspec/shellspec ShellSpec is a full-featured BDD unit testing framework for shell scripts, supporting bash, ksh, zsh, dash, and all POSIX shells. It provid… | 43 | 1396 | stable |
| ashishb/adb-enhanced ADB-Enhanced is a Python-based command-line wrapper around the Android Debug Bridge (adb) that simplifies common Android testing and develo… | 76 | 1392 | active |
| se2p/pynguin Pynguin is a command-line tool that automatically generates unit tests for Python programs using search-based and random testing techniques… | 92 | 1389 | active |
| mariotoffia/FluentDocker A .NET library providing a fluent API for managing Docker and Podman containers, images, and compose stacks locally and remotely. It includ… | 86 | 1387 | active |
| Jackalope Jackalope is a customizable, coverage-guided fuzzer for black-box binaries built on the TinyInst instrumentation library by Google Project … | 73 | 1386 | active |
| airtap/airtap Airtap is a command-line tool for running TAP-producing JavaScript unit tests (e.g. with tape) across many browsers, locally or in the clou… | 26 | 1381 | active |
| puppeteer/replay A TypeScript library providing an API to replay and stringify user flow recordings created with Chrome DevTools Recorder. It includes a CLI… | 90 | 1378 | active |
| Endava/cats CATS (Contract API Testing and Security) is a REST API fuzzer and negative testing tool for OpenAPI endpoints. It automatically generates, … | 92 | 1374 | active |
| TNG/ArchUnitNET ArchUnitNET is a C# library for specifying and asserting architecture rules in automated tests, forked from Java's ArchUnit. It analyzes as… | 91 | 1374 | active |
| eranpeer/FakeIt FakeIt is a header-only C++ mocking framework with an expressive C++11-based API for creating mock objects and verifying method invocations… | 62 | 1371 | stable |
| DiUS/java-faker A Java library that ports Ruby's faker gem to generate realistic fake data such as names, addresses, phone numbers, and many themed categor… | 32 | 4901 | maintenance |
| mozilla/grcov grcov is a fast Rust-based CLI tool that collects and aggregates code coverage data from multiple source files. It processes .profraw and .… | 98 | 1370 | active |
| GoogleChrome/chrome-launcher A Node.js library from GoogleChrome that launches Google Chrome with the DevTools remote-debugging port open, automatically locating the Ch… | 87 | 1367 | active |
| cglib/cglib cglib is a high-level Java bytecode generation and transformation library used to create dynamic proxies, extend classes, and intercept met… | 23 | 4886 | maintenance |
| chipsalliance/riscv-dv RISCV-DV is a SystemVerilog/UVM-based random instruction sequence generator for verifying RISC-V processor designs. It produces randomized … | 75 | 1363 | active |
| rust-pretty-assertions/rust-pretty-assertions A Rust crate that provides drop-in replacements for assert_eq! and assert_ne! macros with colorful, human-readable diffs on failure. It is … | 39 | 1358 | active |
| go-fuzz go-fuzz is a coverage-guided fuzzing tool for testing Go packages with randomized inputs. It is mainly useful for hardening code that parse… | 32 | 4848 | maintenance |
| plantain-00/type-coverage A CLI tool that measures type coverage in TypeScript codebases by calculating the percentage of identifiers whose type is not `any`. It can… | 71 | 1352 | active |
| dotnet/sourcelink Source Link is a set of .NET build tools and NuGet packages that embed source control metadata into binaries, symbols (PDBs), and packages … | 82 | 1350 | stable |
| jetmore/swaks Swaks is a scriptable, transaction-oriented SMTP test tool written in Perl, often called the Swiss Army Knife for SMTP. It supports SMTP, E… | 23 | 1347 | active |
| qdhenry/Claude-Command-Suite A collection of 216+ slash commands, 12 Claude Code Skills, and 54 specialized AI agents that add structured development workflows to Claud… | 57 | 1336 | active |
| mingrammer/flog Flog is a Go CLI tool that generates fake log data in common formats such as Apache common/combined/error, RFC3164/RFC5424 syslog, and JSON… | 30 | 1334 | active |
| pschanely/CrossHair CrossHair is a Python analysis tool that verifies functions against type annotations and contracts using symbolic execution backed by an SM… | 95 | 1333 | active |
| tonybaloney/wily Wily is a command-line application that tracks and reports code complexity and other metrics across the git history of a Python project. It… | 83 | 1329 | active |
| kubeshop/tracetest Tracetest is an open-source trace-based testing tool that builds integration and end-to-end tests on top of OpenTelemetry distributed trace… | 30 | 1329 | active |
| thoughtbot/appraisal Appraisal is a Ruby library that integrates with Bundler and Rake to test your library against different versions of its dependencies in re… | 37 | 1325 | active |
| phpqa A Docker image bundling popular PHP static analysis and quality tools such as PHPStan, PHP-CS-Fixer, PHPMD, PHPCS, PHPCPD, PHPMetrics, and … | 95 | 1321 | active |
| sourcefrog/cargo-mutants cargo-mutants is a mutation testing tool for Rust that automatically injects bugs (mutants) into your code and runs your test suite to see … | 91 | 1315 | active |
| DongTai IAST DongTai IAST is an open-source Interactive Application Security Testing platform that detects vulnerabilities in Java (and some Python) app… | 29 | 1314 | active |
| simplepeng/SpiderMan An Android library that displays crash/exception information directly on the device in a dialog, with options to share the stack trace. It … | 43 | 1313 | stable |
| fetch-mock fetch-mock is a JavaScript library for mocking HTTP requests made with the fetch API, with an intuitive API for routing mocks based on requ… | 80 | 1309 | active |
| giltene/wrk2 wrk2 is a constant-throughput HTTP benchmarking tool based on wrk, modified to produce accurate latency recordings using HdrHistograms. It … | 32 | 4635 | maintenance |
| metacraft-labs/codetracer CodeTracer is a time-traveling debugger that records program execution into a self-contained, shareable trace file. It provides a GUI for s… | 84 | 1306 | active |
| bUnit-dev/bUnit bUnit is a C# testing library for Blazor components that lets tests run like regular unit tests on top of xUnit, NUnit, MSTest, and TUnit. … | 96 | 1304 | active |
| SonarJS SonarSource's static code analyzer for JavaScript, TypeScript, and CSS, providing hundreds of rules for code quality and security. It now a… | 100 | 1302 | active |
| rsmbl/Resemble.js Resemble.js is a JavaScript library for analyzing and comparing images using HTML5 canvas, producing pixel-level diff images and analysis d… | 32 | 4608 | maintenance |
| r-lib/lintr lintr is an R package providing static code analysis for R, checking style adherence, syntax errors, and possible semantic issues. It is hi… | 83 | 1299 | stable |
| reg-viz/reg-suit reg-suit is a command-line tool for visual regression testing that compares current screenshots against previous snapshots and generates HT… | 75 | 1297 | active |
| GoogleChromeLabs/chrome-for-testing Chrome for Testing is a Google-maintained distribution of versioned Chrome, ChromeDriver, and chrome-headless-shell binaries for automated … | 75 | 1297 | active |
| ReactiveCircus/android-emulator-runner A GitHub Action that installs, configures, and runs hardware-accelerated Android Emulators on GitHub Actions Linux and macOS virtual machin… | 82 | 1295 | active |
| spatie/laravel-mail-preview A Laravel package that adds a 'preview' mail transport which stores sent emails locally and shows an overlay link to preview them. It is de… | 70 | 1295 | active |
| treosh/lighthouse-ci-action A GitHub Action that runs Lighthouse audits on URLs and enforces Lighthouse CI assertions or performance budgets within CI workflows. It su… | 60 | 1292 | active |
| smocker-dev/smocker Smocker is a simple and efficient HTTP mock server and proxy designed to help mock the HTTP dependencies of an application, especially for … | 66 | 1285 | active |
| freerange/mocha Mocha is a Ruby library for mocking and stubbing in unit tests, providing a unified syntax for full and partial mocking of test doubles. It… | 75 | 1284 | stable |
| carlosas/phpat PHP Architecture Tester (PHPat) is a PHPStan extension that verifies architectural requirements in PHP codebases, such as which namespaces … | 96 | 1283 | active |
| Appium The official Java language binding for writing Appium automated tests, conforming to the W3C WebDriver Protocol. It integrates with Maven o… | 81 | 1282 | active |
| bug0inc/passmark Passmark is an open-source TypeScript library that extends Playwright to run end-to-end browser regression tests written in plain English. … | 58 | 1280 | active |
| kiwitcms/Kiwi Kiwi TCMS is an open source test case management system for organizing manual and automated testing, featuring test plans, test runs, bug t… | 95 | 1278 | active |
| JustinBeckwith/linkinator Linkinator is a broken link checker that crawls websites, local HTML files, and markdown documentation to find dead links and invalid URLs.… | 97 | 1277 | active |
| open-source-labs/Spearmint Spearmint is an open-source Electron desktop application that generates Jest test code through an accessibility-first graphical interface. … | 61 | 1277 | active |
| ktr0731/evans Evans is an expressive universal gRPC client written in Go, offering both an interactive REPL mode with powerful completion and a stateless… | 23 | 4491 | maintenance |
| iOS Simulator Skill for Claude Code A Claude Code skill (also installable as a plugin) providing 27 Python scripts for building, testing, and automating iOS apps via xcodebuil… | 82 | 1271 | active |
| tokio-rs/turmoil Turmoil is a family of Rust crates for deterministic simulation testing of distributed systems, running multiple concurrent hosts on a sing… | 80 | 1267 | active |
| smart-test-ti/SoloX SoloX is a real-time performance data collection tool for Android and iOS applications, gathering metrics like CPU, memory, FPS, network, a… | 23 | 1266 | active |
| Kspider Kspider is a self-hosted visual web scraping platform written in Java where users define crawler workflows as flowcharts without writing ba… | 15 | 1265 | active |
| GdUnit4 GdUnit4 is an embedded unit testing framework for the Godot 4 game engine, supporting tests written in both GDScript and C#. It integrates … | 99 | 1264 | active |
| benchmark-action/github-action-benchmark A GitHub Action that collects benchmark results from many benchmarking tools and tracks them across CI runs. It stores results on a GitHub … | 91 | 1264 | active |
| CodeIntelligenceTesting/jazzer Jazzer is a coverage-guided, in-process fuzz testing engine for the JVM, based on libFuzzer. It integrates with JUnit 5 and build tools lik… | 82 | 1260 | active |
| mfridman/tparse tparse is a command-line tool that parses and summarizes `go test -` output, showing failures, panics, and package-level summaries with col… | 46 | 1260 | stable |
| plurai-ai/intellagent IntellAgent is a Python framework for diagnosing and optimizing conversational LLM agents through simulated, realistic synthetic user inter… | 55 | 1258 | active |