This repository is the official home of the CSS Working Group's editor drafts, serving as the authoritative source for the development of CSS specifications. It is a hybrid standards development platform, functioning primarily as a specification authoring and build system. Its core function is to store, build, and publish CSS specification documents (in Bikeshed .bs format) along with their associated examples, test data, and issue tracking. The architecture is a monorepo of loosely coupled specification modules (e.g., css-color-4, css-grid-3), each containing its own source file, build instructions (Makefile), and assets. Shared infrastructure includes build scripts (bin/), CI/CD workflows (.github/), and bundled third-party libraries (MathJax, ReSpec, jQuery) for rendering and authoring. The primary data flow involves editing source files, running the Bikeshed preprocessor, and publishing the resulting HTML. The repository contains several hidden gems of high craftsmanship. The color conversion algorithms in css-color-4/conversions.js and deltaE2000.js are production-grade, self-contained implementations of complex color science. The resizeTestHelper.js provides a robust pattern for testing asynchronous browser APIs. The custom diagram elements in css-view-transitions-1 (slides.js, scaler.js) demonstrate a novel approach to embedding interactive documentation. While the specification content is actively maintained with thousands of open issues and recent commits, the repository suffers from significant technical drift. Bundled dependencies like MathJax v2.0, jQuery 1.7.2, and the legacy ReSpec.js are severely outdated, posing security and compatibility risks. The presence of eval usage, plaintext credential references in Makefiles, and mixed tooling (Bikeshed vs. ReSpec) further contributes to a high technical debt profile. Despite this, the core mission of developing CSS specifications is executed effectively, and the reusable components are genuinely valuable.

EPUBCheck is the official W3C conformance checker for EPUB publications. It validates EPUB 2 and EPUB 3 files against the respective specifications, including OCF packaging, OPF metadata, XHTML/SVG content, CSS, media overlays, navigation documents, and accessibility metadata. The tool operates as a Java command-line application and library, using a modular checker architecture where dedicated handlers validate specific resource types (e.g., OCFChecker, OPFChecker, OPSChecker, CSSChecker). Validation is driven by a combination of RelaxNG schemas for structural rules and Schematron for cross-cutting constraints. The project includes an extensive test suite using Cucumber/BDD features and thousands of test EPUB packages covering error and valid scenarios across all profile extensions (ePub 3, EDUPUB, dictionaries, indexes, multiple renditions, previews, and region-based navigation).

This is the working repository of the W3C CSS Houdini Task Force: a collection of editor's drafts (specifications) for browser APIs that expose CSS internals to JavaScript. The content is written in Bikeshed (.bs) format and processed by a Python build pipeline (bin/build-markdown.py, bin/build-index.py, Makefiles, GitHub Actions) into the HTML specs served via GitHub Pages. The repository contains formal, normative algorithm definitions for the CSS Paint API (registerPaint), CSS Layout API (registerLayout), CSS Animation Worklet (registerAnimator), CSS Properties & Values API, CSS Typed OM, Font Metrics API, Box Tree API, and Worklets. It is not a runtime application or a data pipeline — it is documentation-as-code with build automation and small runnable examples — but it is classified as "application" because its dominant content is executable artifacts (worklet demo code, CI scripts, build tooling) rather than data assets. The highest-craft content is in the spec sources: the CSS Typed OM draft defines a complete, self-contained algebra for CSS numeric values (base types, percent hints, sum values, unit conversion, canonical units) plus a reify/serialize pair that converts between internal CSS representations and typed JavaScript objects. The CSS Layout API draft specifies a work-queue processing model, global scope selection, and structured serialization for worklet data — all reusable algorithmic patterns for browser-engine implementers and polyfill authors. The included paint-worklet demos (circle, arc, chat) are isolated, copy-pasteable examples of the registerPaint contract. Maintenance is active: the last commit is recent, the Typed OM changes section references live GitHub issues/PRs, and the CI installs pinned dependencies. However, there is notable internal drift: css-parser-api has been moved to WICG (its Overview.bs is blank), worklets/Overview.bs now redirects to the HTML Standard, scroll-customization-api remains an explainer without a formal spec, and several Typed OM reification entries are explicitly empty stubs or marked with open issue markers. The 2018 issue-list artifacts and README_old.md files add historical clutter. For engineers, the practical value is threefold: (1) reference implementations of the Houdini API surface for anyone building polyfills, browser features, or CSS tooling; (2) a clean, reusable Bikeshed-spec build/deploy pipeline (Python scripts + GitHub Action) that can be extracted to any W3C-style spec repo; and (3) minimal worklet starter examples. It is not code you deploy — it is a standards workshop, and the quality bar is standards-writing rigor rather than software architecture.

This is the official W3C WebTransport specification repository. It defines a JavaScript API for bidirectional, multiplexed network communication over QUIC and HTTP/3, providing reliable streams and unreliable datagrams. The repository contains the spec source in Bikeshed format (index.bs), supporting documents (explainer, use-cases, security questionnaire), and functional sample implementations (echo client/server and a WebCodecs-based video streaming demo). The core deliverable is the specification, while the samples serve as proof-of-concept implementations. The codebase is a hybrid: primarily a standards document, but includes runnable demo applications that illustrate the API usage patterns. The spec is still in early draft stage and references evolving IETF protocols.

This repository is the official W3C WebSub specification (formerly PubSubHubbub), a decentralized publish/subscribe protocol over HTTP. It is not a software application or data pipeline; it contains the normative ReSpec specification documents, implementation reports, and W3C governance metadata. The core deliverable is source.html, with staged snapshots for FPWD, Working Draft, and the 2018 Recommendation. The spec defines three roles — publisher, subscriber, and hub — and specifies discovery via link rel=hub/self, hub subscription/unsubscription with lease management, content distribution via POST, and optional authenticated distribution using HMAC signatures. It also includes conformance classes and implementation report templates that multiple independent projects (Google, Mastodon, Twitch, Superfeedr, etc.) have used to self-certify interoperability.

The W3C Editing repository hosts specifications and examples for web editing APIs, including EditContext, Clipboard API, and Input Events. It provides static HTML documentation and runnable demos that illustrate how to use these specifications. The repository is actively maintained by the Web Editing Working Group and includes a reusable polyfill for the 'intentions' feature that demonstrates non-obvious skill in handling keyboard events.

The w3c/html-aria repository maintains the ARIA in HTML W3C specification — a normative document defining which ARIA roles, states, and properties are permitted on each HTML element, plus the implicit ARIA semantics of native HTML. It is not a conventional application; it is a standards artifact with engineered supporting infrastructure: a ReSpec-based spec source (`index.html`) auto-published to gh-pages via GitHub Actions, a corpus of standalone HTML conformance test pages in `tests/`, and a cross-tool implementation report in `results/implementation-results.html`. The repo functions as the authoritative rulebook that accessibility conformance checkers (Nu HTML Validator, axe-core, IBM Equal Access, ARC Toolkit) implement against, so its 'production output' is normative rules consumed by validator software. The test corpus encodes each normative rule as a discrete, self-contained HTML page with explicit pass/fail expectations — for example, pages verifying that `aria-hidden="true"` is forbidden on focusable elements, that `aria-rowspan` must not coexist with a native `rowspan`, and which roles are allowed on `button`, `summary`, `img`, and `li`. The implementation report tracks, per rule and per vendor tool, whether the rule is implemented (yes/partial/missing), linking to tool-specific GitHub issues. The contribution workflow enforces cross-repo coordination: normative changes require a corresponding web-platform-tests PR and coordination with checker maintainers before merging, which is an unusually well-governed process for a spec repository. Maintenance is steady: commits continue through late 2026, the implementation report was updated in March 2026, Dependabot monitors GitHub Actions, and the W3C auto-publish pipeline runs on every push. Technical drift is low — the spec deliberately tracks the WHATWG HTML Living Standard, deprecates (rather than abandons) outdated ARIA features, and is built on the actively maintained ReSpec toolchain. The main fragility is external: implementation gaps in vendor checkers are documented openly in the report, and cross-repo synchronization with WPT and checker projects creates coordination risk, but the repo itself is current and professionally curated.

This repository serves as the central hub for the W3C Positive Work Environment Community Group, which maintains and evolves the W3C Code of Ethics and Professional Conduct (now referred to as the Code of Conduct). The system consists of static HTML documents (some using ReSpec for technical report formatting), Markdown files, presentation templates, and educational resources. Key functions include: maintaining the Code of Conduct document and its update procedures; documenting dispute resolution processes including mediation, investigations, and disciplinary actions; describing the Ombudsperson program; providing meeting facilitation training materials (Running Better Meetings guides); managing inclusion fund proposals and communications; and offering multilingual versions of core documents. The architecture is a static document repository with presentation layers powered by Shower.js and custom CSS frameworks. External dependencies include ReSpec for document formatting and Shower.js for slide presentations, both loaded from W3C domains.