Open-source alternatives to Rewrite

jscodeshift is a JavaScript AST transformation toolkit and codemod engine designed for large-scale code refactoring and structural migrations. It provides a set of utilities to parse source code into abstract syntax trees, programmatically modify those trees, and convert them back into source text. The tool distinguishes itself by preserving original source formatting and stylistic properties during the transformation process. It utilizes a builder for generating structurally valid AST nodes and integrates interchangeable parsing engines to support different language standards and experimenta

Comby is a command-line utility designed for structural code search and transformation across diverse programming languages. It functions as a code transformation engine that identifies and modifies source code patterns by utilizing syntax-aware templates, ensuring that operations respect language boundaries such as nested blocks, strings, and comments. The tool distinguishes itself by mapping various programming languages to a unified structural representation, allowing for consistent pattern matching that ignores irrelevant whitespace and formatting. It performs these operations by executin

Tinymist is a comprehensive suite of tools for Typst document authoring, serving as a language server, document compiler, and project manager. It provides a standardized language service via the Language Server Protocol to enable editor features such as autocompletion, navigation, and semantic highlighting. The project distinguishes itself by integrating a TCP-based live preview server for real-time visual rendering and an advanced static analysis tool that utilizes abstract syntax trees and bidirectional type checking. It also includes a project management system capable of handling multi-fi

GoGoCode is an AST-based code transformation toolkit that enables developers to query, match, and rewrite JavaScript source code using jQuery-style selectors and wildcard patterns. At its core, it provides a programmatic code refactoring library that manipulates parsed AST nodes, allowing precise structural modifications without worrying about formatting differences. The toolkit also functions as a JavaScript AST query engine, finding code patterns through snippet-based matching with wildcards that capture unknown or variable-length fragments. What distinguishes GoGoCode is its callback-drive

Django-upgrade is a command-line tool that automatically modernizes legacy Python and Django codebases by rewriting outdated syntax patterns into current idioms. It operates as a static analysis linter and source code transformation engine, parsing files to identify deprecated constructs and replacing them in place while preserving project integrity. The software uses a rule-based transformation architecture driven by abstract syntax tree parsing to execute modular refactoring tasks. Developers can configure target version settings to ensure the tooling only applies updates appropriate for th

swift-syntax is a library for parsing, manipulating, and generating Swift source code. It provides a source-accurate abstract syntax tree representation of Swift code, acting as a parser, transformer, and code generator. The project serves as the infrastructure for Swift macro development, enabling the expansion and transformation of source code during compilation. It is used to build compiler tooling for static analysis, formatting, and automated refactoring. The system covers a broad range of source analysis capabilities, including the ability to convert source code into structured trees f

lsp-mode is a Language Server Protocol client and IDE feature set for Emacs. It functions as a semantic code analysis tool and JSON-RPC communication layer that connects the editor to external language servers to provide intelligent code completion and real-time diagnostics. The project also serves as a Debug Adapter Protocol client, enabling interactive debugging sessions and breakpoint management. This allows for stepping through code and inspecting variables via a standardized protocol, including support for debugging within Docker containers. The system covers a broad range of developmen

This project is a static analysis linter, code quality tool, and language auditor for Rust. It functions as an automated refactoring system designed to identify common mistakes and suggest idiomatic improvements for Rust source code. The tool identifies non-idiomatic patterns, performance bottlenecks, and code smells to improve the overall correctness and quality of the code. It specifically audits memory safety by flagging suspicious use of unsafe blocks and pointer manipulations and detects inefficient operations to optimize execution speed. The analysis surface covers coding style enforce

Rubberduck is a development environment extension designed for legacy Visual Basic and Visual Basic for Applications projects. It functions as a comprehensive suite that integrates directly into the host editor to provide static code analysis, automated refactoring, and project management capabilities. The tool distinguishes itself by implementing a formal grammar-based parsing engine that transforms source code into a structured abstract syntax tree. This allows for deep static analysis, enabling the identification of defects and style inconsistencies. It further supports development workflo

ZLS is a language server for the Zig language that implements the Language Server Protocol to provide IDE-like intelligence. It functions as a code intelligence provider, static code analysis tool, and automated refactoring engine for Zig projects. The server integrates directly with the Zig compiler toolchain to derive precise type information and perform semantic analysis. It uses this integration to surface real-time compilation errors as editor diagnostics and to provide semantic syntax highlighting based on resolved types rather than regex patterns. The project covers a wide range of de

Codemod is a set of software tools for performing structural source code transformations. It functions as an automated codebase migration tool that utilizes abstract syntax tree manipulations rather than simple regular expressions to execute large-scale refactors across multiple files. The project distinguishes itself through an interactive transformation interface that provides colored diffs, allowing users to manually review, accept, or modify each match. It also supports a distributed refactoring workflow, which enables the segmentation of a codebase into assigned work blocks to divide mig

ts-migrate is an automated migration tool designed to transform JavaScript source code into compiling TypeScript files. It functions as a code migration framework that uses abstract syntax trees to perform large-scale refactoring and structural changes across a project. The tool provides a customizable framework for defining plugin-based transformation rules, allowing for the automation of specific code changes. It includes specialized engines for converting JSDoc type definitions into native TypeScript annotations and a utility for suppressing compiler errors by inserting type assertions or

c2rust is a source-to-source translation suite and C-to-Rust transpiler designed to convert C source code and libraries into functionally equivalent unsafe Rust code. It operates as a pipeline that preserves original behavior and data structures, producing translated code that compiles as compatible shared libraries or Rust crates. The system includes an automated Rust refactoring framework that uses pattern-based AST rewriting to transform unsafe Rust into safe, idiomatic constructs. It utilizes an ownership inference engine to determine when raw pointers can be converted into safe reference

This tool is a command-line utility designed to automatically detect and correct coding standard violations in PHP source files. It functions as a static analysis and refactoring engine that ensures consistent project-wide formatting by applying predefined community conventions or custom organizational rules. The project distinguishes itself through a modular rule-based engine that supports both automated style correction and codebase modernization. It allows developers to update legacy syntax to align with newer language versions and testing framework requirements, facilitating the adoption

Tern is an editor-independent code analyzer and static analysis engine for JavaScript. It functions as a language server that provides semantic intelligence by parsing source code into abstract syntax trees to infer types and resolve symbols without requiring manual type annotations. The engine distinguishes itself through the use of JSON-based type definitions, which allow it to describe library signatures and external dependencies without needing the original source code. It also features a plugin system that enables the extension of server functionality to support custom loaders or framewo

This project is a suite of abstract syntax tree transformation tools designed to automate the migration of source code to newer versions of React. It provides a set of scripts that programmatically modify code structures to replace deprecated APIs and component patterns with modern equivalents. The toolkit specializes in converting class components into functional components using arrow functions and prop destructuring. It also includes utilities for modernizing JSX syntax, updating deprecated lifecycle methods to stable versions, and migrating legacy string-based references to callback refs.

lua-language-server is a static analysis tool and type checker for the Lua language that implements the Language Server Protocol. It provides a system for detecting type mismatches, unused code, and logic errors in source files. The project features an inference-based type system that deduces variable types and supports optional annotations and meta files to enforce type safety. It allows for the definition of custom types and function signatures, including support for overloads and member visibility controls. The server provides a broad set of IDE capabilities, including real-time code auto

Roo-Code is an integrated development environment extension that functions as an autonomous software engineering agent. It connects large language models directly to your local file system and terminal, enabling the agent to interpret natural language requirements and execute complex development workflows. The project distinguishes itself through a model-agnostic orchestration layer that allows developers to connect various large language model backends to their local workspace. By utilizing an iterative tool-use loop, the agent decomposes high-level tasks into sequential steps, interacting w

YouCompleteMe is a completion engine and semantic code analyzer for the Vim editor. It provides an integrated suite of development tools, including a Language Server Protocol client and a semantic analyzer that utilizes Clang to offer context-aware symbols and type-based highlighting. The project distinguishes itself through specialized semantic completion for C-family languages and JavaScript, offering identifiers, snippets, and automatic imports. It provides advanced visual feedback such as inlay hints for type information and parameter names, as well as semantic highlighting based on the a

This project is a language extension for VS Code that provides comprehensive Go language support. It functions as a language server client, a debugger interface, and a toolchain manager to facilitate Go application development. The extension distinguishes itself by integrating a full suite of toolchain management capabilities, allowing for the installation and configuration of required binaries, linters, and compiler versions directly within the editor. It also provides deep integration for interactive debugging via Delve, supporting remote target debugging, process attachment, and program st

vimplus is a Vim configuration framework and IDE distribution that provides a set of pre-configured settings and a plugin management system. It functions as a curated collection of tools designed to standardize the development environment. The project distinguishes itself through multiple deployment methods, including a bash-based editor provisioner for multi-user configuration and a pre-configured Ubuntu-based container image for immediate environment provisioning without manual installation. The framework covers a broad range of editor capabilities, including symbol navigation, project-wid

RLS is a language server that provides language intelligence for the Rust programming language. It implements the Language Server Protocol to enable a standardized communication layer between the Rust compiler and various editor clients. The project focuses on providing real-time code completions, symbol navigation, and type information. It also supports automated structural changes, such as workspace-wide symbol renaming, to maintain semantic correctness during refactoring. The system incorporates static code analysis for linting and formatting, alongside a mechanism for incremental compila

google-java-format is a Java code formatter and style enforcement tool. It reformats Java source code to adhere to a standardized style guide, ensuring consistent layout and indentation across entire projects or individual files. The project functions as a build pipeline linting tool for continuous integration workflows and as an IDE formatting plugin to replace native editor formatting. It can be embedded as a formatting library within code generation software to ensure machine-written output remains human-readable. The tool provides capabilities for reorganizing source code indentation and

autopep8 is a Python static code styler and formatter designed to automatically rewrite source code to comply with the PEP 8 style guide. It functions as a recursive code cleaner that identifies and fixes indentation, whitespace, and syntax irregularities across entire projects. The tool performs structural refactoring using abstract syntax tree transformations to execute non-whitespace changes, such as shortening long lines and improving identity tests. It includes an aggressive refactoring mode for complex style violations and supports selective formatting via inline markers to disable chan

GPT-Engineer is an autonomous agent and framework designed for AI-assisted software development. It functions as a generative codebase architect that translates natural language requirements into complete, functional software projects by reading and writing files directly to the local file system. The platform distinguishes itself through an agentic workflow orchestrator that sequences complex programming tasks into manageable, iterative steps. It supports multi-modal input processing, allowing users to incorporate visual data like screenshots or diagrams to guide UI generation. Furthermore,

This project is a comprehensive, curated directory of static analysis, linting, and security scanning utilities. It serves as a central resource for developers to discover, compare, and select tools based on specific programming languages, licensing models, and integration requirements. The directory distinguishes itself by providing deep metadata for each listed utility, including community-driven popularity rankings, maintenance status, and deployment methods. By aggregating these tools into a single searchable index, it enables teams to identify solutions for enforcing coding standards, ma

This project is a build orchestration engine and development toolkit designed for managing large-scale monorepos. It provides a unified workspace environment that maps project relationships and dependencies, enabling the system to perform intelligent impact analysis and execute only the tasks affected by specific code changes. The system distinguishes itself through a persistent daemon that monitors file changes for near-instant feedback and a content-addressable caching mechanism that stores task outputs to prevent redundant computation across local and remote environments. It further suppor