Autoflake removes unused imports and unused variables from Python code.

A tool to find common security issues in Python code.

A linting engine supporting custom project-specific rules.

Safe code refactoring for modern Python. Bowler is a refactoring tool for manipulating Python at the syntax tree level. It enables safe, large scale code modifications while guaranteeing that the resulting code compiles and runs. It provides both a simple command line interface and a fluent API in Python for generating complex code modifications in code.

Design by contract for Python. Write bug-free code. By adding a few decorators to your code, you get for free tests, static analysis, formal verification, and much more.

A tool for ensuring Python code is secure.

Dodgy is a very basic tool to run against your codebase to search for "dodgy" looking values. It is a series of simple regular expressions designed to detect things such as accidental SCM diff checkins, or passwords or secret keys hard coded into files.

ENRE (ENtity Relationship Extractor) is a tool for extraction of code entity dependencies or relationships from source code. ENRE-py is a ENtity Relationship Extractor for Python based on Python Language Services of The Standard Library.

A framework for creating lint rules and corresponding auto-fixes for source code.

Signatures for entire Python programs. Extract the structure, the frame, the skeleton of your project, to generate API documentation or find breaking changes in your API.

IT, Inspector Tiger, is a modern python code review tool / framework. It comes with bunch of pre-defined handlers which warns you about improvements and possible bugs. Beside these handlers, you can write your own or use community ones.

Autocompletion/static analysis library for Python.

Parse lint errors and report them to Github as comments on a pull request.

mbake is a Makefile formatter and linter. It only took 50 years!

Check McCabe complexity.

A static type checker that aims to combine the benefits of duck typing and static typing, frequently used with MonkeyType.

Tool for scanning Python packages for known vulnerabilities. Developed by the Python Packaging Authority (PyPA) and supported by Trail of Bits and Google. Scans Python environments and requirements files to identify vulnerable packages and suggests remediation. Supports GitHub Actions, pre-commit hooks, and multiple vulnerability service integrations.

Find SQL injection vulnerabilities in Python code.

A tool for programmatically detecting common mistakes in Python code, such as references to undefined variables and type errors. It can be extended to add additional rules and perform checks specific to particular functions.

(Formerly pep8) Check Python code against some of the style conventions in PEP 8.

Check compliance with Python docstring conventions.

Check Python source files for errors.

Looks for programming errors, helps enforcing a coding standard and sniffs for some code smells. It additionally includes pyreverse (an UML diagram generator) and symilar (a similarities checker).

A static code analyzer / language server for Python, written in Rust, focused on type checking and readable output.

Pyra is a high-level linter static analyzer for data science applications written in Python, that helps developers identify potential issues in their data science code written in Python, as an extension of Lyra.

A fast, scalable type checker for large Python codebases. Pyre-check has been superseded by Pyrefly, its next iteration.

A fast, incremental type checker and language server for Python, providing IDE features like code navigation, semantic highlighting, and code completion.

Static type checker for Python, created to address gaps in existing tools like mypy.

Rate how well a Python project complies with the best practices of the Python packaging ecosystem, and list issues that could be improved.

A tool based on Facebook's pyre-check to identify potential security issues in Python code identified with taint analysis.

Intelligent Python code quality analyzer with CFG-based cyclomatic complexity analysis, dead code detection, clone detection (Type 1-4), and coupling metrics. Uses tree-sitter for parsing. Written in Go.

A static analysis tool for detecting security vulnerabilities in Python web applications.

A static type analyzer for Python code.

A tool (and pre-commit hook) to automatically upgrade syntax for newer versions of the language.

A Python tool that computes various metrics from the source code.

A tool for refurbishing and modernizing Python codebases. Refurb is heavily inspired by clippy, the built-in linter for Rust.

Fast Python linter, written in Rust. 10-100x faster than existing linters. Compatible with Python 3.10. Supports file watcher.

Python dependency vulnerability scanner designed to enhance software supply chain security by detecting packages with known vulnerabilities. Checks Python dependencies against a database of known security vulnerabilities and provides detailed reports. Supports CI/CD integration and multiple output formats.

An extremely fast Python type checker written in Rust.

A linter, formatter for finding and removing unused import statements.

Find unused classes, functions and variables in Python code.

The strictest and most opinionated python linter ever.

A command-line tool for archiving, exploring and graphing the complexity of Python source code.

Monitor code complexity using radon.

Symbolic execution engine for testing Python contracts.

DynaPyt is a framework for writing dynamic analyses for Python. The analyses can also modify runtime values to alter the execution.

Design-by-contract library supporting behavioral subtyping There is also a wider tooling around the icontract library such as a linter (pyicontract-lint) and a plug-in for Sphinx (sphinx-icontract).

Runtime Type Checking for Python 3.

Creates reports of over 400 rule patterns for feature detection (e.g. the use of cryptography or version control in apps).

ast-grep is a powerful tool designed for managing code at scale using Abstract Syntax Trees (AST). Think of it as a hybrid of grep, eslint, and codemod, with the ability to search, lint, and rewrite code based on its structure rather than plain text. It supports multiple languages and is designed to be extensible, allowing you to register custom languages.

Multi-language maintainability analyzer. Computes cyclomatic and cognitive complexity, Halstead volume, afferent/efferent coupling and maintainability index, detects communities in the dependency graph, and generates an explorable HTML report plus JSON, Markdown, SARIF and OpenMetrics output. Single fast binary with no runtime dependency, and a built-in MCP server so AI agents can query codebase structure before refactoring.

A linter and formatter to help you to improve copywriting, correct spaces, words, punctuations between CJK (Chinese, Japanese, Korean).

Checks your code and infra (various Git repositories supported, cloud stacks, CLI, Web Interface platform, integrationss available) for security and quality issues. Code Scanning/SAST/Linting using many tools/Scanners deduplicated with One Report (AI optional).

A language-agnostic linter that keeps code, documentation, and configuration in sync and enforces strict formatting and validation rules.

Statically generates a call graph image and displays it on screen.

Commercial Static Code Analysis which runs locally, but uploads the results to its cloud for presentation.

Commercial Static Code Analysis which doesn't require pre-compilation.

Structural source code analyzer by NASA's Jet Propulsion Laboratory.

Opensource Static Code Analysis for security teams with Inter file dataflow taint analysis. Built for finding vulnerabilities, advanced structural search, derive insights and supports MCP server.

Codemodder is a pluggable framework for building expressive codemods. Use Codemodder when you need more than a linter or code formatting tool. Use it to fix non-trivial security issues and other code quality problems.

Ecosystem for structural matching JavaScript and TypeScript code. Offers search tool that understands code structure. Available as CLI tool and Visual Studio Code extension. It helps to search code faster and more accurately making you workflow more effective. Soon it will offer ESLint plugin to create your own rules in minutes to help with assuring codebase quality.

Corgea is an AI-powered SAST scanner that helps developers find and fix insecure code. It finds business logic flaws, broken authentication, API vulnerabilities, and more with little false positives. Additionally, it automatically writes security fixes for them to approve. Corgea integrates with GitHub, GitLab, Azure DevOps, IDEs and CLI. It is free to try it.

Synopsys Coverity supports 20 languages and over 70 frameworks including Ruby on rails, Scala, PHP, Python, JavaScript, TypeScript, Java, Fortran, C, C++, C#, VB.NET.

A Github Action for linting C/C++ code integrating clang-tidy and clang-format to collect feedback provided in the form of thread comments and/or annotations.

Free, anonymous SCA + SAST scanner. SCA: scans npm, PyPI, Maven, Go, Cargo, Ruby, NuGet dependencies for CVEs (OSV/KEV/EPSS), typosquats and supply-chain risk. SAST: pattern + taint analysis for 15 languages, 300+ rules. No account, no source upload. Available as a web tool, zero-install CLI and GitHub Action.

Multi-language Static Application Security Testing (SAST) platform that detects critical vulnerabilities, including hardcoded secrets, weak cryptography, backdoors, SQL injections, insecure configurations, etc.

Emerge is a source code and dependency visualizer that can be used to gather insights about source code structure, metrics, dependencies and complexity of software projects. After scanning the source code of a project it provides you an interactive web interface to explore and analyze your project by using graph structures.

Security scanner that pairs taint analysis with separation-logic checks in Z3, plus an optional LLM layer. Symbolic frontends cover Python, Java, JavaScript/TypeScript, C/C++ and C#. LLM findings are reported in a separate tier from symbolic ones, and the LLM layer runs on any OpenAI-compatible endpoint, including a local one.

Grep rough audit - source code auditing tool.

AI agent security scanner. Detects behavioral vulnerabilities (prompt injection, infinite loops, token bombing, SQL injection via LLM) across 11 framework adapters including LangChain, CrewAI, and pydantic-ai. Audits MCP servers. Maps findings to EU AI Act, OWASP LLM Top 10, and NIST AI RMF.

Joern is a platform for analyzing source code, bytecode, and binary executables. It generates code property graphs (CPGs), a graph representation of code for cross-language code analysis. Code property graphs are stored in a custom graph database. This allows code to be mined using search queries formulated in a Scala-based domain-specific query language. Joern is developed with the goal of providing a useful tool for vulnerability discovery and research in static program analysis.

Copy/paste detector for programming source code. Finds duplicated blocks in 200+ file formats — JavaScript, TypeScript, Python, Java, C#, C/C++, Go, Rust, PHP, Ruby and more — using token-based detection. Supports configurable thresholds and ignore patterns, git blame integration, and reporters for console, HTML, JSON, Markdown, SARIF and badges. Runs via CLI, in CI pipelines, or as a library; bundled by MegaLinter and Codacy.

Keploy is an open-source testing platform that helps developers automate and streamline their testing process. It provides API, and integration testing agents, generating tests, mocks/stubs for APIs that actually work. Additionally, Keploy offers an AI-powered Unit Testing Agent that generates stable, useful unit tests directly in your GitHub PRs and in VSCode, helping catch errors and improve code quality.

Code health metrics from the terminal. Grades a project from A++ to F-- on cognitive complexity, duplication, indentation, Halstead effort and file size, and lists the files to look at first. Separate commands report cyclomatic and cognitive complexity per function, duplicates, code smells and the Maintainability Index. From git history it finds hotspots, code ownership and temporal coupling, and measures which files a diff reaches. A CI gate fails when a changed file gets worse.

Automated translation platform for code comments and docstrings across 20+ file types. Eliminates language barriers in international software collaboration. Supports 100+ language pairs with syntax protection. Integrates into CI/CD pipelines like Ruff. 10-20x faster with concurrent processing.

Lizard is an extensible Cyclomatic Complexity Analyzer for many programming languages including C/C++ (doesn't require all the header files or Java imports). It also does copy-paste detection (code clone detection/code duplicate detection) and many other forms of static code analysis. Counts lines of code without comments, CCN (cyclomatic complexity number), token count of functions, parameter count of functions.

Mega-Linter can handle any type of project thanks to its 70+ embedded Linters, its advanced reporting, runnable on any CI system or locally, with assisted installation and configuration, able to apply formatting and fixes

A static analyzer designed to easily reuse abstract domains across widely different languages (such as C and Python).

OpenRewrite fixes common static analysis issues reported through Sonar and other tools using a Maven and Gradle plugin or the Moderne CLI.

OpenStaticAnalyzer is a source code analyzer tool, which can perform deep static analysis of the source code of complex systems.

Precaution is a static analysis security tool (SAST) designed to find potentially critical vulnerabilities in source code prior to production. It is available as a CLI, GitHub Action, and GitHub App.

Code audit tool for Python and JavaScript. Wraps pycodestyle, pydocstyle, PyFlakes, Mccabe, Pylint, and more

A static file linter that allows you to write custom rules using regular expressions (RegEx).

Deterministic, zero-LLM code-health analysis. Scores every file 1-10 for defect risk, maintainability, and performance from 25 markers: McCabe complexity, LCOM4 cohesion, god classes, Rabin-Karp clone detection, change entropy, and untested hotspots. Adds a dependency graph, dead-code detection, git-history signals (churn, ownership, co-change), and concrete graph-aware refactoring plans. Ships as a CLI, an MCP server, and a VS Code extension across 15 languages.

Semantic version control CLI that provides entity-level diffs, blame, and impact analysis on top of git. Uses tree-sitter to parse 26 languages and builds a cross-file dependency graph with structural hashing. Commands include sem diff, sem blame, sem graph, and sem impact for blast-radius analysis of code changes.

A fast, open-source, static analysis tool for finding bugs and enforcing code standards at editor, commit, and CI time. Its rules look like the code you already write; no abstract syntax trees or regex wrestling. Supports 17+ languages.

Scan is a free open-source DevSecOps platform for detecting security issues in source code and dependencies. It supports a broad range of languages and CI/CD pipelines. Note: ShiftLeft rebranded to Qwiet AI in 2023, which was subsequently acquired by Harness in September 2025. This open-source project is no longer maintained.

Sigrid helps you to improve your software by measuring your system's code quality, and then compares the results against a benchmark of thousands of industry systems to give you concrete advice on areas where you can improve.

Dead code detection, security scanning, secrets detection, and code quality analysis for Python, TypeScript, and Go. Framework-aware analysis with 98% recall. Includes CI/CD GitHub Action, VS Code extension, and MCP server for AI agent integration.

SonarQube for IDE (formerly SonarLint) is a free IDE extension available for IntelliJ, VS Code, Visual Studio, and Eclipse, to find and fix coding issues in real-time, flagging issues as you code, just like a spell-checker. More than a linter, it also delivers rich contextual guidance to help developers understand why there is an issue, assess the risk, and educate them on how to fix it.

Static Code Analysis for C/C++, Java, C#, Python, and RPG III and RPG IV versions (including free-form).

Static Reviewer executes code checks according to the most relevant Secure Coding Standards, OWASP, CWE, CVE, CVSS, MISRA, CERT, for 40+ programming languages, using 1000+ built-in validation rules for Security, Deadcode & Best Practices Available a module for Software Composition Analysis (SCA) to find vulnerabilities in open source and third party libraries.

Combination of multiple linters to install as a GitHub Action.

A commercial static analysis platform that allows for scanning of multiple languages (C/C++, Android, C#, Java, JS, PHP, Python, Node.JS, Ruby, Fortran, and Swift).

Tencent Cloud Code Analysis (TCA for short, code-named CodeDog inside the company early) is a comprehensive platform for code analysis and issue tracking. TCA consist of three components, server, web and client. It integrates of a number of self-developed tools, and also supports dynamic integration of code analysis tools in various programming languages.

Multi-language linter targeting anti-patterns that appear disproportionately in AI-generated code: duplicated blocks across files, excessive nesting, magic numbers, Single Responsibility violations, and linter suppressions added without justification. Covers Python, TypeScript, JavaScript and Rust from one configuration, ships a pre-commit hook per rule, and emits text, JSON or SARIF for CI.

Linter for integrating annotated TODOs with your issue trackers

Modern repositories include many technologies, each with its own set of linters. With 30+ linters and counting, Trunk makes it dead-simple to identify, install, configure, and run the right linters, static analyzers, and formatters for all your repos.

Code visualization tool that provides code analysis, standards testing, metrics, graphing, dependency analysis and more for Ada, VHDL, and others.

Entity-level semantic merge driver for git. Resolves false conflicts that line-based merge produces when independent changes touch the same file. Parses functions and classes via tree-sitter, matches by name, and merges at the entity level. Benchmarked at 100% clean merges vs git's 48% on a 31-scenario suite.