webkit.org

webkit.org
Name	WebKit
Developer	Apple Inc., KDE, Google, Igalia
Initial release	2003
Repository	multiple
Programming language	C++, Objective-C
License	LGPL, BSD

webkit.org

WebKit is an open-source web browser engine project with roots in KDE, Apple Inc., KDE Software Compilation, KHTML, and KJS that provides rendering, layout, and JavaScript execution for major browsers and platforms including Safari (web browser), Google Chrome, Microsoft Edge (Chromium), Opera (web browser), and embedded systems used by Nintendo and Samsung Electronics. The project integrates technologies from projects such as WebKitGTK, QtWebKit, Epiphany (web browser), Safari Technology Preview, and components used by Cocoa applications and Web Inspector tooling. Development of WebKit has intersected with organizations and projects including Apple Public Source License, FreeBSD, Chromium (web browser project), Google Summer of Code, and companies like Adobe Systems, Intel, and ARM Holdings.

History

WebKit originated when Apple Inc. forked the KHTML and KJS engines from the KDE project to implement a browser engine for Safari (web browser) with contributions from engineers associated with Dave Hyatt, Brendan Eich, Don Melton, and later contributors connected to Jaguar (operating system) releases. Over time, the codebase interacted with projects and events such as Open Source, BSD licenses, the Apple Public Source License, and corporate initiatives by Google, leading to the creation of forks and related projects including Chromium (web browser project) and the Blink (browser engine). Key milestones involved collaborations with organizations like Igalia, participation in Google Summer of Code, and integration into platforms including iOS, macOS, Windows, and Linux distributions such as Ubuntu and Debian. The engine’s evolution reflected influences from standards bodies like the World Wide Web Consortium, the Web Hypertext Application Technology Working Group, and features driven by interoperability testing from Mozilla Foundation and WHATWG.

Architecture and Components

WebKit’s architecture comprises a multi-process model and components such as the WebCore layout engine, the JavaScriptCore engine, networking stacks, and developer tools like Web Inspector. The WebCore module handles parsing, rendering, and CSS cascade interactions informed by specifications from the World Wide Web Consortium and WHATWG, while JavaScriptCore implements ECMAScript features aligning with ECMAScript editions and test suites like Test262. WebKit integrates with platform-specific APIs including Cocoa, GTK+, Qt, and WPE for embedded devices used by vendors such as Samsung Electronics and Raspberry Pi Foundation. The architecture interacts with multimedia codecs and frameworks like FFmpeg, OpenGL, Metal (API), Vulkan, and Core Animation, and supports web standards implemented by projects and initiatives including WebRTC, Service Worker, IndexedDB, WebAssembly, and Shadow DOM.

Development and Contribution Model

The WebKit project employs a distributed version control and code review workflow coordinated through repositories and tools used by GitHub, GitLab, and specialized review systems inspired by practices at Apple Inc. and Google. Contributors range from corporate engineers at Apple Inc., Google, Igalia, Nokia, Samsung Electronics, and Microsoft to independent developers associated with communities like KDE, GNOME, and academic participants from institutions such as MIT, Stanford University, and University of Cambridge. The project participates in outreach programs including Google Summer of Code, follows coding standards influenced by LLVM Project and Clang style guides, and coordinates security disclosures with vendors and entities like CERT Coordination Center and standards organizations such as the IETF.

Security and Privacy Features

WebKit incorporates security mechanisms including process isolation, sandboxing, and mitigations against vulnerabilities cataloged by initiatives like the Common Vulnerabilities and Exposures program; it aligns with disclosure practices advocated by organizations such as Open Web Application Security Project and coordinates patches with platforms like iOS and macOS. Privacy features include tracking prevention approaches similar to proposals from Mozilla Foundation and Google Chrome, support for Content Security Policy, SameSite cookie policies shaped by IETF discussions, and integration with platform privacy controls from Apple Inc. and Google. WebKit’s security model also addresses cryptography interoperability with standards and entities including Internet Engineering Task Force, Certificate Authority Browser Forum, OpenSSL, and NSS implementations.

Browser and Platform Implementations

WebKit powers browsers and platforms such as Safari (web browser), WebKitGTK, Epiphany (web browser), QtWebKit, WPE for embedded devices, and vendor ports used by Samsung Internet, Nintendo Switch, and other embedded platforms from OEM partners. Historically it influenced projects like Google Chrome prior to the creation of Blink (browser engine) and remains implemented in mobile ecosystems including iOS where platform rules mandate WebKit-based engines for third-party browsers, as well as desktop environments on macOS, Linux, and select BSD distributions.

Community and Governance

Governance of WebKit involves maintainers from corporations such as Apple Inc., contributors from firms like Igalia and Google, and community participants from organizations including KDE, GNOME, and academic institutions. Decision-making and release coordination reference practices from open-source governance models used by projects such as the Linux kernel and Apache Software Foundation, and community engagement occurs through mailing lists, issue trackers, and events like W3C meetings, FOSDEM, WebKit Contributors Meeting, and conferences attended by developers from Mozilla Foundation, Microsoft, and Google. The ecosystem includes downstream integrators, third-party extension developers, security researchers, and standards participants from groups like WHATWG and W3C.

Category:Web engines