Open-source alternatives to Comby

Rector is an automated PHP refactoring and modernization tool designed to upgrade language versions and modernize syntax using predefined rules. It functions as a static analysis engine that inspects code structures and types to identify refactoring targets without executing the code. The project provides a framework for defining custom transformation logic to automate project-specific changes. It distinguishes itself by offering specialized capabilities for migrating legacy or custom frameworks to modern alternatives and converting docblock annotations into native language attributes. The s

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

Recast is a JavaScript AST parser and printer designed for automated code refactoring. It converts source code into abstract syntax trees that can be modified and then printed back into source code. The project focuses on formatting-preserving transformations, storing original whitespace and indentation metadata within syntax tree nodes to reconstruct code without losing its original layout. It also generates character-level source maps to maintain precise correspondences between original input and transformed output. The toolkit includes utilities for syntax tree manipulation using a visito

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

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

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

Typos is a source code spell checker and automated typo fixer designed to detect and correct spelling errors across programming languages and project files. It functions as a CI spelling validator and SARIF compatible linter, allowing projects to prevent misspelled text from reaching production. The tool features a customizable dictionary engine that utilizes TOML configuration and locale-specific dictionaries to manage project-specific terminology. It differentiates itself by splitting programming language identifiers into individual words for validation and verifying the spelling of filenam

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

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

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

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

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

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,

Symbols-outline.nvim is a Neovim plugin that renders a dedicated sidebar panel displaying a hierarchical tree view of code symbols. It communicates with language servers to extract structural code information, functions, classes, and variables, allowing users to browse and navigate document structures directly from an interactive interface. The plugin tracks active cursor movements in code buffers to automatically highlight corresponding items in the outline panel. Users can interactively collapse or expand nested tree branches, jump directly to selected symbol locations in source files, prev

Babel is a pluggable JavaScript compiler and transpiler that converts modern ECMAScript syntax into backwards-compatible versions of the language. It functions as an abstract syntax tree manipulator, parsing source code into a hierarchical structure to traverse and modify nodes for custom code transformations. The system utilizes a plugin-driven architecture to apply specific transformation rules and supports presets that bundle multiple plugins into named configuration groups. This enables the transformation of experimental syntax and the injection of non-global polyfills to ensure consisten

AST Explorer is a web-based tool for parsing source code into abstract syntax trees and visualizing the resulting tree structure. It serves as a code inspector and transformation playground, allowing users to explore the structural representation of various programming languages through an interactive browser interface. The tool provides a transformation environment where users can apply modification rules to parsed trees to test code modification logic. It features bidirectional mapping that highlights matching tree nodes and source text simultaneously as the cursor moves across the editor.

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

Reason is a strongly typed functional language and multi-target compiler designed to produce either JavaScript for web environments or native machine code for operating systems. It serves as an OCaml-compatible language that shares an abstract syntax tree with OCaml, providing a practical syntax for the OCaml ecosystem. The project functions as a type-safe frontend language, incorporating JSX support to build user interfaces through structural elements that translate into type-safe function calls. It enables deep integration with the JavaScript ecosystem, allowing the use of existing librarie

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

This project is an agentic development framework and autonomous software engineering system. It utilizes a coordinated network of specialized LLM agents to automate the full software development lifecycle, from codebase exploration and architectural planning to implementation and automated refactoring. The system is distinguished by an agentic memory system and a test-driven development orchestrator. It maintains project continuity across sessions by capturing architectural learnings and state in a persistent semantic database and enforces code quality through an automated cycle of generating

This is a TC39 proposal to add declarative pattern matching syntax to the ECMAScript language. It introduces a match expression that allows developers to inspect and branch on data structures using patterns with destructuring, guards, and logical combinators. The proposal defines a custom matcher protocol via a well-known symbol, enabling objects to implement user-defined matching logic with arbitrary extraction and decomposition. The proposal supports matching against literal primitives using SameValue equality with special handling for signed zero and NaN, as well as relational comparison

Memgraph is an in-memory, distributed graph database designed for high-performance labeled property graph management. It utilizes a Cypher query engine for declarative data retrieval and manipulation, providing a scalable knowledge graph backend that integrates vector search and graph traversals. The system distinguishes itself as a real-time graph analytics platform, employing native C++ and CUDA implementations to execute complex network analysis and dynamic community detection on streaming data. It provides specialized support for AI integration, including GraphRAG capabilities, the constr

This project is an AI assistant for Visual Studio Code that utilizes a large language model to generate code and answer programming queries. It functions as a code generator and assistant, enabling the insertion of AI-generated snippets directly into active source files and providing a conversational interface via a side panel chat. The extension facilitates structural refactoring, optimization, and debugging of selected code blocks through natural language prompts. It also generates natural language explanations and technical documentation for complex code segments without requiring the user

ts-morph is a TypeScript AST manipulation library and a high-level wrapper for the TypeScript compiler API. It provides a programmatic interface for analyzing, modifying, and generating TypeScript source code, serving as a tool for automated code refactoring and source code generation. The library simplifies the process of navigating and inspecting project structures by offering an object-oriented abstraction over the underlying compiler API. It allows for the programmatic transformation of existing codebases to automate structural updates and bulk code migrations. Its capabilities cover sta

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

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

Vis is a terminal-based modal text editor that utilizes vi keybindings and a system of structural regular expressions. It functions as a scriptable environment where Lua is used for configuration, custom key mappings, and plugin development. The editor distinguishes itself through a syntax highlighting system based on Parsing Expression Grammars and a pattern matching engine that treats text as a structure for complex search and replace operations. It also integrates directly with the system shell, allowing users to pipe text ranges to external commands and capture the resulting output. The