Read the rendered documentation — user guides, technical architecture, and visual diagrams.

xudanu (Xudanu) is a modern Rust and WebAssembly implementation inspired by the Xanadu Project and its Udanax Gold (Xanadu 92.1) system.

It reinterprets and evolves foundational ideas in generalized hypertext and data structures for use in contemporary systems.

The canonical name of the project is xudanu (lowercase).

• Used for: code, crates, CLI tools, and repository naming
• Example: use xudanu::..., xudanu serve

The capitalized form “Xudanu” may be used in prose or discussion when referring to the system more generally.

The original Xanadu work introduced a deeply innovative model for structured documents, versioning, and linking. xudanu continues that lineage by:

• Translating core ideas into Rust
• Supporting WebAssembly (WASM) execution
• Refining and optimizing core data structures and algorithms
• Making the system usable in modern environments (web, services, distributed systems)

This is not just a port—it is an evolution of those ideas.

xudanu builds on a long lineage of research and engineering:

Xanadu Project (1960s–1990s)
        ↓
Xanadu 92.1 (Udanax Gold)
        ↓
xudanu (Rust / WebAssembly)

The original Xanadu system explored new models for hypertext, identity, and structure that remain relevant today.

The Udanax Gold source code was released open-source on August 23, 1999 under the MIT/X11 license. See udanax.xanadu.com for the original announcement, license, and supporting documents.

The Xanadu project, initiated in the 1980s, explored a radically different approach to hypertext and information systems. Its implementation, Xanadu 92.1 (later released as Udanax Gold), introduced novel data structures and models.

xudanu is a modern reimplementation and evolution of those ideas.

This project:

• Translates and adapts concepts from Udanax Gold into Rust
• Introduces optimizations and architectural changes
• Targets modern execution environments including WebAssembly

We aim to preserve the strengths of the original system while making it usable in today’s ecosystem.

xudanu exists to continue and extend ideas that were ahead of their time.

By combining those foundational concepts with modern tools such as Rust and WebAssembly, we aim to:

• Improve safety and performance
• Enable new applications
• Support experimentation and real-world deployment

This project is an ongoing evolution, not a static port.

Developer Preview — the system is functional and tested (1,799 tests passing) but APIs and data formats may evolve. Snapshot migration ensures your data survives upgrades. Versioned wire protocol supports backward-compatible API changes.

Feature Status — comprehensive tracking of all Xanadu, Udanax Gold, and Xudanu features with implementation status. Covers Nelson's 17 Rules, core data structures, wire protocol, frontend, security, federation, and Xudanu-exclusive additions (LLM integration, cryptographic provenance, CRDT collaborative editing).

• Rust 1.56 or later (edition 2021). Latest stable recommended. Install via rustup:

  curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh

• A browser — Firefox, Safari, or Chrome.

git clone https://github.com/jonesd/xudanu.git
cd xudanu
cargo build --features server -p xudanu

This builds the xudanu-server binary at ./target/debug/xudanu-server.

In-memory (no persistence, good for trying it out):

./target/debug/xudanu-server run 127.0.0.1:8080

With persistent storage:

./target/debug/xudanu-server init /tmp/xudanu-data
./target/debug/xudanu-server run 127.0.0.1:8080 /tmp/xudanu-data --static-dir original-code/xanadugold/src-rust/static

Data is saved to server.json on graceful shutdown (Ctrl-C) and restored on next start.

If you downloaded a pre-built binary and see "Apple could not verify xudanu-server":

xattr -cr /path/to/xudanu-server

Or right-click the binary → Open → click Open again in the dialog.

Go to http://127.0.0.1:8080 — you'll see the document editor.

• Technical Architecture — a detailed walkthrough of the core data structures, algorithms, and performance characteristics (O-trees, GrandMap, Canopy pruning, H-trees, transclusion queries, DagWood concurrent edits). Recommended for all developers and architects.
• Xudanu in One Page — a concise overview of the entire system.
• 30 Years of Hypertext Innovation — historical context connecting Xanadu to modern hypertext.
• Storage System — content-addressed chunk store and manifest design.
• Notification System — content watch, similarity matching, and micropayments.
• All documentation — index of all available docs.
• Server README — CLI reference, web UI guide, TLS setup, federation, and architecture details.

Documentation is served at dgjones.info/xudanu/ via GitHub Pages.

• Workflow: .github/workflows/deploy-docs.yml
• Trigger: Any push to main that changes files in docs/**
• Source: The entire docs/ directory is uploaded as the Pages artifact
• No build step — static HTML/Markdown served as-is

To add or update documentation:

1. Add/edit files in docs/ (HTML files match the dark theme; Markdown files in docs/dev/)
2. If adding a new page, link it from docs/index.html
3. Commit and push to main — GitHub Actions deploys automatically

xudanu is licensed under the Apache License 2.0.

Portions of this project are derived from Udanax Gold (Xanadu 92.1), which was released under the Xanadu X11 license (a permissive license similar to MIT).

The original license is included in:

original-code/xanadugold/LICENSE

Both licenses are permissive.

This means you may:

• Use this software commercially
• Modify and distribute it
• Integrate it into proprietary systems

Requirements:

• Preserve license notices
• Include attribution to the original Xanadu/Udanax work

This project acknowledges the pioneering work of the Xanadu project and Udanax Gold.

xudanu is an independent effort and is not affiliated with or endorsed by Autodesk or the original Xanadu contributors.

Contributions are welcome.

By contributing, you agree that your contributions will be licensed under the Apache License 2.0.

We acknowledge the original Xanadu vision and the engineers who built Udanax Gold. Their work continues to influence how we think about information systems today.