Open-source alternatives to HTMLHint

TSLint is an extensible static analysis tool that checks TypeScript source files against a configurable set of lint rules. It scans code by walking the parsed TypeScript abstract syntax tree, applying rule objects to detect readability, maintainability, and functionality errors. The tool supports rule severity configuration, inline suppression through comment directives, and automatic attachment of fix objects for correcting violations. The project provides a framework for developing custom lint rules and formatters, allowing teams to enforce project-specific coding conventions beyond the bui

Semgrep is a static analysis security testing tool designed to identify vulnerabilities and logic errors by matching source code against declarative patterns. It functions as an automated scanner that integrates into development workflows to detect insecure code patterns and enforce coding standards before deployment. The engine utilizes a language-agnostic intermediate representation and a modular parser architecture to normalize diverse programming languages into a unified format. This allows for consistent rule execution across different codebases, enabling users to perform custom structur

This project is a software engineering style guide and a curated collection of architectural patterns and coding standards. It provides a multi-language coding standard to ensure maintainable software across Ruby, Python, JavaScript, and Swift. The project establishes a development workflow specification for version control, continuous integration, and peer review to maintain a linear project history. It also includes a web accessibility framework based on ARIA and WCAG standards, using design tokens and semantic HTML patterns to build inclusive interfaces. The guides cover a broad range of

JSHint is a JavaScript static analysis tool and linter designed to detect errors and enforce coding standards. It functions as a syntax validator that scans source code to identify potential logic problems and programming mistakes before the code is executed. The tool provides a command line interface for analyzing files and directories. It supports the export of analysis results into standardized formats such as Checkstyle for integration with external build tools. Analysis is managed through a system of linting rule management and environment global configuration. This includes the ability

This project is a comprehensive reference guide for writing clean, semantic, and maintainable HTML markup based on modern web standards. It provides a set of rules for implementing semantic HTML standards, using meaningful structural elements instead of generic containers to improve document hierarchy and machine readability. The guide establishes specific conventions for HTML formatting, covering indentation, tag casing, and source code organization to improve codebase maintainability. It also serves as a web accessibility reference, detailing the implementation of ARIA roles, alternative te

Taiko is a browser automation framework and web end-to-end testing library used to perform programmatic user actions and verify application behavior. It functions as a headless browser testing tool capable of simulating real interactions and asserting page states in Chromium and Firefox. The project includes a browser interaction recorder that captures live actions and exports them as executable JavaScript automation scripts. It also serves as a web accessibility auditor, analyzing pages to detect accessibility violations and ensure compliance with inclusive design standards. The framework c

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 a CSS linter and static analysis tool designed to identify syntax errors, logic flaws, and problematic patterns in Cascading Stylesheets. It functions as a command line validator that verifies code quality and enforces consistent styling and coding standards without requiring a web browser. The analyzer distinguishes itself by incorporating web accessibility auditing to detect patterns that hinder users with disabilities. It also performs browser compatibility checking to identify non-standard hacks and missing vendor prefixes, and provides performance optimization analysis to

Proselint is a prose linter and rule-based text analyzer designed to identify stylistic errors, clichés, and jargon in written text. It scans documents against a curated registry of linguistic and typographic rules to maintain professional editorial standards and improve writing quality. The project functions as a command line text processor, a programmable analysis library, and a git pre-commit hook. Its modular architecture allows the core engine to be embedded into other applications, exposed via a REST API, or integrated into text editors. The tool supports recursive directory traversal

Overcommit is a Git hook manager and pre-commit validation framework designed to automate the execution of scripts and checks during various Git events. It serves as a workflow automation tool that ensures code quality and project standards are met before changes are committed or pushed to a remote repository. The system distinguishes itself through a comprehensive YAML-based configuration that allows for detailed hook behavior control, including file execution filtering, conditional skipping, and the management of hook dependencies. It provides specialized roles such as a commit message vali

This project provides a framework for managing multi-agent systems, designed to automate complex software development, infrastructure, and business workflows. It functions as a multi-agent workflow orchestrator that routes tasks to domain-specific workers while maintaining state persistence and infrastructure automation. By leveraging large language models, the system decomposes high-level objectives into actionable plans, ensuring that complex operations are executed with consistency and reliability. The framework distinguishes itself through its hierarchical agent registry and policy-driven

Amplication is a low-code API platform and backend service generator designed to accelerate the development of business domain services. It automates the creation of APIs and data models through schema-driven code generation, transforming structured definitions into executable backend source code. The platform functions as a developer portal orchestrator that establishes standardized workflows and golden paths for software delivery. It enforces organizational coding standards and best practices by applying live templates and predefined blueprints across all generated services. The system inc

Cytoscape.js is a JavaScript library designed for rendering interactive node-link diagrams and analyzing complex network structures directly within a web browser. It functions as a comprehensive framework for building responsive graph interfaces, providing the tools necessary to visualize relational datasets and manage hierarchical data models. The library distinguishes itself through a modular architecture that supports custom layout algorithms and rendering styles, allowing for the integration of physics-based engines to organize complex network structures automatically. It utilizes an even

This project is a collection of educational resources and structured curricula designed for learning JavaScript. It provides a programming course, a coding bootcamp, and a web development tutorial to guide learners from basic syntax to advanced programming patterns. The materials cover frontend development, including the creation of dynamic user interfaces and the management of remote data via HTTP requests. The curriculum includes instructional guides on using JavaScript to interact with web services and manipulate browser elements. The scope of the project extends to asynchronous API integ

This project is a web accessibility checklist and inclusive design framework. It serves as a digital inclusion guide and audit tool for verifying that web content is perceivable, operable, and welcoming to a diverse global audience. The project provides a structured review process for WCAG compliance, focusing on auditing HTML structure, ARIA roles, keyboard navigation, and visual accessibility. It includes specific standards for reviewing language, typography, and color contrast to ensure inclusive content design. The framework covers broader capability areas including device compatibility

Vetur is a Visual Studio Code extension that provides comprehensive language support for Vue single-file components. It parses .vue files into separate template, script, and style regions, then delegates each region to its own language service for independent processing. This architecture enables IntelliSense, type-checking, formatting, and linting across all embedded languages within a Vue file. The extension distinguishes itself through deep integration with Vue's component model. It infers TypeScript types for template expressions by analyzing component props, data, and computed properti

Error Prone is a static code analyzer and Java compiler extension that identifies common programming mistakes during the build process. It functions as a compiler wrapper that flags potential errors as compile-time failures to prevent bugs from reaching execution. The tool integrates directly into the Java compilation workflow to provide compile-time validation. It allows for the definition of custom linting rules and analysis checks to enforce specific coding standards and detect prohibited API usage. The system utilizes abstract syntax tree analysis and type-aware pattern matching to inspe

tota11y is an in-browser accessibility testing tool that runs as a bookmarklet, scanning any live web page and overlaying visual indicators directly on elements that violate common accessibility guidelines. All analysis happens client-side without any server communication, making it a self-contained auditing and education tool. The tool uses a plugin-driven rule engine where each accessibility check is encapsulated as a separate module, and results are displayed through a toggleable toolbar interface that uses CSS-based colored labels and icons positioned over the page elements. Users can ena

This repository is a collection of React educational materials and reference implementations. It provides a series of source code examples, solved exercises, and sample projects designed to support a structured learning path for the React library and its ecosystem. The project serves as a frontend development reference, offering versioned code snapshots that allow for the comparison of custom implementations against working solutions. These samples demonstrate the creation of single-page applications, focusing on component-based user interface design and state-driven rendering. The repositor

PMD is a multi-language static code analyzer used to identify programming flaws, unused variables, and dead code without executing the program. It functions as a code smell detector and coding standard enforcer, ensuring source code adheres to specific naming conventions, structural requirements, and project style guides. The project features an XPath-based rule engine that allows users to define custom analysis patterns using queries against an abstract syntax tree. It also includes a copy-paste detector to identify duplicated code blocks across multiple files and a visual rule designer for

Standard is a zero-configuration static analyzer, linter, and formatter for JavaScript. It functions as a style guide that enforces consistent coding rules and identifies programming errors without requiring manual configuration files. The tool distinguishes itself by providing an automatic code fixer that scans source files to correct style violations and ensure a uniform codebase. It implements a predefined rule set to eliminate the need for project-specific configuration. The project covers a broad range of static analysis capabilities, including support for experimental language syntax a

AngleSharp is an HTML5 DOM parser and web scraping framework designed to parse HTML5, SVG, and MathML documents into a W3C compliant document object model. It functions as a programmatic HTML generator and a CSS selector engine for querying and locating specific elements within a DOM. The project provides tools for simulating browser environments to automate web interactions, navigate URLs, and submit forms. It includes a dedicated HTML and CSS minifier to reduce the file size of web assets by removing unnecessary characters. The library supports HTML DOM manipulation and the extraction of s

This project is a comprehensive front-end development guide and roadmap designed to help engineers master the skills and professional standards required for modern web development. It serves as a technical reference for mastering HTML, CSS, and JavaScript, providing structured learning paths and a map of the professional competencies needed to transition from a beginner to a professional web engineer. The resource functions as a categorized directory and ecosystem overview of the JavaScript landscape. It catalogs industry-standard frameworks, libraries, and utilities, offering specific recomm

parse5 is a WHATWG HTML parser and serializer for Node.js. It transforms HTML strings into a document object model and converts those trees back into valid HTML strings, following the logic defined by the HTML Living Standard. The project functions as a streaming HTML processor, using incremental parsing to handle large documents in chunks. It includes an HTML5 compliant tokenizer that uses a state-machine approach to break input into tokens according to official web specifications. The toolset covers HTML document parsing, serialization, and real-time rewriting via streams. These capabiliti

This project is a comprehensive JavaScript programming tutorial and language reference. It serves as a web development education resource providing instruction on modern language fundamentals, object-oriented design, and advanced asynchronous programming patterns. The resource functions as both a frontend development guide and a technical reference. It covers core language features such as closures, prototypes, promises, and typed arrays, while providing practical lessons on managing browser data and handling network requests. The content spans several key capability areas, including browser

htmlparser2 is a collection of tools for high-performance markup parsing, DOM manipulation, and incremental stream processing. It functions as an HTML and XML parser that converts markup strings into structured object trees, alongside a streaming markup parser designed for memory-efficient processing of large documents. The project includes a DOM manipulation library for querying, modifying, and serializing document object model trees. It also provides a web feed parser to extract structured metadata and entries from RSS, RDF, and Atom feeds. The library covers broad capabilities in data par