Code Quality GitHub Repositories (2026) · Open Source Tools

An opinionated, curated list of tools for enforcing software development standards: one recommended tool per job, with limits.

A powerful C# Roslyn analyzer that uses static analysis to detect bugs, surface security issues, and enforce best practices—helping developers and AI write more reliable code.

Discover the best developers — and become one. Drop a GitHub handle for a 0–100 value & trust score in 30s: see your gaps, discover top devs, get found. Exposes PR farmers, AI bots & fork-hoarders. Deterministic scoring, self-hostable.

Regal is a linter and language server for Rego, bringing your policy development experience to the next level!

Static code analysis for Kotlin

The missing linter and lsp for AI coding assistants. Validate CLAUDE.md, AGENTS.md, SKILL.md, hooks, MCP. Plugin for all major IDEs included, with autofixes.

⚙️ The static code analysis tool you need for your HTML

The open source taint analysis engine for the AI era. A formal dataflow analysis tool you can customize and self-host, built so AI agents drive your application security analysis without burning tokens on every scan. AI-ready open source alternative to Semgrep Pro and CodeQL.

⚙️ Scan your Go, Java, Kotlin, PHP, Python, JavaScript, TypeScript, .NET projects at GitHub with Qodana. This repository contains Qodana for Azure, GitHub, CircleCI and Gradle

Architecture quality gate for polyglot codebases: declare components and allowed dependencies, fail the build on drift

Checkstyle is a development tool to help programmers write Java code that adheres to a coding standard. By default it supports the Google Java Style Guide and Sun Code Conventions, but is highly configurable. It can be invoked with an ANT task and a command line program.

Source code spell checker

Open-source CI/CD security tool: finds the security checks your pipeline is missing, and the ones that can never fail the build. GitHub Actions, GitLab CI and more.

A plugin for Flake8 finding likely bugs and design problems in your program. Contains warnings that don't belong in pyflakes and pycodestyle.

Open source AI code review for coding agents. A separate reviewer checks every change your agent writes before you push, in Claude Code, Codex, Cursor and Cline. No account or key of its own.

A CLI tool to check whether a specific composer package uses imported symbols that aren't part of its direct composer dependencies

PHP_Depend is an adaptation of the established Java development tool JDepend. This tool shows you the quality of your design in terms of extensibility, reusability and maintainability.

A tool to verify that your files are in harmony with your .editorconfig

A SkunkScore Calculator for Ruby Code -- Find the most complicated code without test coverage!

Local codebase intelligence CLI + MCP server for AI coding agents: SQLite code graph, 28 languages, 287 commands, 246 MCP tools, change-safety gates, audit evidence, zero API keys.