Excalidraw

Quickdraw is an MIT-licensed, open-source infinite-canvas whiteboard SDK for React, React Native/Expo, and plain JavaScript applications. It provides freehand pressure ink, highlighters, shapes, arrows, lines, text, sticky notes, images, selection and transformation tools, laser presentation pointers, themes, grids, palm rejection, and PNG export. Its data model emits JSON-safe diffs for real-time synchronization over an application-chosen transport, with support for persistence, undo/redo, and stroke-by-stroke replay. The project provides separate core, React, and React Native packages; the core is plain ESM with zero runtime dependencies and can run in modern browsers without a build step. The repository states that it is free for commercial use and has no license fee.

tldraw is an open-source SDK for building infinite-canvas applications in React, including whiteboards, diagramming tools, and workflow-mapping interfaces. Its canvas engine supports custom shapes, tools, bindings, UI components, drawing, geometric shapes, rich text, arrows, snapping, media, image export, and runtime control through an Editor API. The repository also documents self-hosted real-time collaboration through @tldraw/sync, browser-based rendering, and canvas primitives for AI integrations. It can be installed as an npm package and includes starter kits for applications such as workflow builders, agent canvases, and AI chat interfaces. The starter kits are MIT-licensed.

reladraw is a text language and command-line tool for creating diagrams with relative positioning. It sits between automatic layout systems such as Mermaid, Graphviz, and D2 and manually positioned editors such as draw.io: users declare nodes, relationships, labels, and relative placement without specifying absolute coordinates. The parser and layout engine resolve the declarations into a diagram, while the tool reports issues such as overlaps, crossed edges, and text overflow without requiring a rendered preview. Its TypeScript CLI converts `.reladraw` files to SVG, and the repository also provides a browser version and an optional agent skill. The project is early-stage, its syntax is subject to change, and the code is licensed under Apache-2.0.

Diagram Design is a diagram-generation skill for Claude Code, Codex, Factory Droid, and Pi. It produces self-contained HTML and SVG diagrams through 39 editorial visual types, including architecture, flowchart, sequence, state-machine, data-flow, timeline, Sankey, Wardley map, kanban, user journey, deployment, dependency graph, UML class, story map, and database-schema diagrams. It can read a website to match its brand, and can redraw draw.io or Mermaid sources at a selected format, size, and detail level. Its semantic system patterns describe behavior separately from layout, so queues, policy traces, and trust boundaries can use an existing diagram type without adding new layout types. The repository supplies each type in minimal-light, minimal-dark, and full-editorial variants. Static HTML is the default; optional accessible motion is available for ordered explanations. The diagrams require no build step, JavaScript, or external image dependency.

Whiteboard is an open-source desktop app for humans and coding agents to architect software in a shared workspace. It connects to agents such as Claude Code and Codex, giving them an SDK for drawing diagrams and describing their work on an in-app canvas. Visualizations including sequence diagrams, entity-relationship diagrams, and agent-trace quotations can link directly to underlying code, while the code-review interface provides VS Code keybindings and LSP support. Whiteboard includes a semantic, AST-aware diff viewer written in Rust. It summarizes large added functions as pseudocode and can collapse or hide changes such as tests and documentation; a WebAssembly-based plugin system makes these rules customizable. Its decision-log tools let agents query and link their traces so users can inspect requirements, implementation choices, and autonomous decisions. The app runs against local checkouts, is distributed for macOS, Windows, Ubuntu, and Fedora, and is licensed under the MIT License. It is self-hostable, although hosted team functionality is planned. Current limitations include no file editing within Whiteboard and limited support for reviewing multiple repositories together.