AFFiNE is a cross-platform, block-based knowledge management application that combines notes, whiteboards, and databases in a local-first, real-time collaborative environment. Built on the BlockSuite editor framework, it features a modular architecture with extensible components, AI-powered capabilities (Copilot), and support for embedding external content. The application consists of a web client, desktop client (Electron), and mobile clients (iOS/Android), backed by a Node.js/NestJS server with Prisma ORM and Rust performance modules. Data is synchronized via Yjs CRDTs with a custom storage layer (nbstore) for offline-first capabilities.
tldraw is a monorepo providing an open-source infinite-canvas SDK for building collaborative whiteboard/drawing applications in React. The core library (`@tldraw/editor`, `@tldraw/tldraw`) exposes a highly extensible shape/tool/overlay system with signal-based reactivity, real-time synchronization (`@tldraw/sync-core`), and a full UI component library (menus, toolbars, dialogs, style panels, commenting). The repository also includes a production-grade web application (tldraw.com) with authentication (Clerk), file management, real-time sync via Cloudflare Durable Objects, MCP server integration, and a Zero-based relational data layer for multi-user features. Additional assets include a VS Code extension, an AI agent starter kit, a documentation site, an extensive example gallery (~100+ recipes), and deployment infrastructure for Cloudflare Workers, Vercel, and template demos. The architecture is modular—core packages have minimal dependencies—and the codebase demonstrates strong engineering practices: comprehensive unit and e2e testing, a custom validation library with path-aware errors, an efficient small-set implementation (`ArraySet`), and a debounce utility that returns cancelable promises.
Excalidraw is an open-source virtual whiteboard and diagramming application, published both as a hosted PWA (excalidraw-app) and as an npm library (@excalidraw/excalidraw). The system provides an infinite canvas with hand-drawn-style rendering, supporting a wide range of shapes (rectangles, ellipses, arrows, lines, freedraw, text, sticky notes, images, frames, embeddables) and tools (laser pointer, eraser, bucket fill, lasso selection, shape recognition). It features real-time collaboration via WebSocket (socket.io) and Firebase, with end-to-end encryption, cursor sharing, and follow/unfollow. The architecture is a React-based single-page application with a modular monorepo structure: the core editor logic resides in packages/excalidraw, element manipulation in packages/element, geometry utilities in packages/math, shared constants and data structures in packages/common, and export helpers in packages/utils. State management uses Jotai atoms and a custom action registration system (ActionManager). The editor renders to an HTML5 canvas with a separate SVG overlay for interactive elements. Key entry points include packages/excalidraw/index.tsx (library export) and excalidraw-app/index.tsx (hosted app bootstrap). Data flows from user interactions through actions to element mutations, scene updates, and canvas re-rendering. External dependencies include Firebase (Firestore, Storage), socket.io, Radix UI, Jotai, roughjs, and various build tools. The codebase also includes an AI-assisted text-to-diagram feature (TTD dialog) that converts Mermaid syntax into Excalidraw elements via streaming SSE and auto-fix logic.
MiroTalk P2P is a self-hosted, open-source WebRTC video conferencing application that enables real-time peer-to-peer video calls, audio calls, screen sharing, chat, whiteboard collaboration, file sharing, and recording. The architecture consists of a Node.js/Express server with Socket.IO for signaling and a REST API (v1) for programmatic meeting management, token generation, and statistics. The client is a single-page application with modular JavaScript files handling UI components, media processing, accessibility, and integrations. Key features include end-to-end encrypted media (SRTP/DTLS), noise suppression via RNNoise AudioWorklet, live captions (Web Speech API and server-side Whisper transcription), ChatGPT integration, OIDC authentication, JWT-based API security, and an embeddable support widget. The system is designed for privacy: no persistent storage of signaling data, chat, or media; recordings stay in the browser as Blobs. Deployment options include Docker, Kubernetes, and bare-metal, with support for CoTURN TURN servers, ngrok tunneling, and email alerts via Nodemailer. The codebase is well-structured with separate modules for security (XSS sanitization, input validation, host protection), logging, and integration helpers, though the main server.js is monolithic (~2000 lines) and the client-side CSS is large (~5000 lines combined).
This repository is a curated markdown list of companies that use non-whiteboard interview techniques. Despite having 50K+ stars, it is not a software application in any meaningful sense — it is a community-maintained README with a CI pipeline that validates markdown formatting and link integrity. The only source file, index.js, is an empty module export (effectively a no-op). All 'functionality' lives in the CI workflow and package.json linting configuration. The architecture is trivial: GitHub Actions runs two jobs on PRs/pushes to main. The 'remark' job installs Node dependencies and runs remark-cli with a set of linting plugins to enforce markdown style (alphabetized lists, no tabs, no trailing slashes on URLs, etc.). The 'links' job uses lychee-action to verify all URLs in README.md return valid HTTPS responses. There is no application logic, no data processing, no API — just static file validation. The repository's value is entirely in the README content (the company list), not in any code. The CI pipeline is a standard, unremarkable markdown linting setup. The last commit was in June 2026, but the project has no real development trajectory — it accepts PRs that add list entries and runs CI to validate them. The codebase itself has no reusable components; the CI workflow is generic boilerplate that could be copied from any markdown linting tutorial.