How popular is book on GitHub?

astrid-runtime/book has 7,456 stars and 32 forks on GitHub, and gained -3 stars in the last 7 days.

What license does book use?

astrid-runtime/book is released under the Apache-2.0 license.

astrid-runtime/bookPublic

The canonical reference for Astrid: kernel, capsules, host ABI, IPC, and the security model.

AI summary: The canonical reference documentation for Unicity Astrid OS, covering its kernel, security model, and host ABI.

Star on GitHub

Stars: 7.5K; +1 today
Forks: 32
Watchers: 3
Open issues: 0
Open PRs: 1
Contributors: ~2
Commits: 19
Branches: 3

PerlApache-2.0Created Jun 6, 2026Last push 26d ago+-3 stars this week+-10 this month

Quick answers

What is book?: The canonical reference documentation for Unicity Astrid OS, covering its kernel, security model, and host ABI.
What does book do?: The Unicity Astrid OS Book serves as the comprehensive, canonical reference guide for the Astrid operating system. Built utilizing the mdBook framework from the Rust ecosystem, it extensively documents the core architecture including the kernel, the capsule model, the host ABI, the internal bus, and the comprehensive security model. The repository contains both statically written markdown chapters and dynamic appendices, such as capability catalogs and ABI error codes, which are generated directly from the operating system's source code. It is designed to be the ultimate source of truth for anyone developing for, or contributing to, the Unicity Astrid OS.
Who is book for?: This book is intended for systems programmers, kernel developers, and security researchers actively working with or studying the Unicity Astrid operating system. It requires a foundational understanding of operating system concepts, ABIs, and system architecture.
How do I get started with book?: mdbook serve --open
How popular is book on GitHub?: astrid-runtime/book has 7,456 stars and 32 forks on GitHub, and gained -3 stars in the last 7 days.
What license does book use?: astrid-runtime/book is released under the Apache-2.0 license.

Star history

since Jul 29, 2026

7.5K stars as of Oct 1, 2026. Measured daily since Jul 29, 2026; GitHub no longer exposes earlier star timestamps.

Update history

1 recorded

Oct 4, 2026Previously tracked as unicity-astrid/book; its 1 daily snapshot and 2 trending appearances were merged into this profile. Stars: 7,503 on 2026-07-29 under the old name, 7,456 on 2026-10-01 (-47).

Contribution activity

commits per day, last 52 weeks

18 commits in the last yearLessMore

Signals and awards

derived from tracked data

Permissive license
Apache-2.0
Continuous integration
Automated checks passing

What book does

The Unicity Astrid OS Book serves as the comprehensive, canonical reference guide for the Astrid operating system. Built utilizing the mdBook framework from the Rust ecosystem, it extensively documents the core architecture including the kernel, the capsule model, the host ABI, the internal bus, and the comprehensive security model. The repository contains both statically written markdown chapters and dynamic appendices, such as capability catalogs and ABI error codes, which are generated directly from the operating system's source code. It is designed to be the ultimate source of truth for anyone developing for, or contributing to, the Unicity Astrid OS.

This book is intended for systems programmers, kernel developers, and security researchers actively working with or studying the Unicity Astrid operating system. It requires a foundational understanding of operating system concepts, ABIs, and system architecture.

Comprehensive architecture documentation: Details the complete design of the Astrid OS kernel, bus, and security models.
Dynamic appendices: Automatically generates technical references like ABI error codes and capability catalogs from source code.
mdBook integration: Leverages the fast and standard mdBook toolchain to render clean, readable documentation.
Cross-referencing: Utilizes custom Perl scripts to generate intelligent 'See also' footers across different chapters.
Polyrepo parsing: Capable of reading and synthesizing documentation data from multiple related repositories in the project.

Where teams use it

OS development

Kernel developers use the book as a strict reference guide while modifying the core architecture of Astrid OS.

Application building

Software engineers refer to the generated host ABI documentation when writing user-space applications for the operating system.

Security auditing

Security researchers study the detailed security model and capability catalogs to understand the OS's isolation guarantees.

Contributor onboarding

New contributors read the foundational chapters to quickly grasp the capsule model and overarching system design.

Getting started: mdbook serve --open

README

main branch

The Astrid Book

The canonical reference for Astrid: the kernel, the capsule model, the host ABI, the bus, and the security model.

Built with mdBook.

mdbook serve --open

The reference appendices (capability catalog, host ABI error codes, topic registry) are generated from the Astrid source by tools/gen-appendices.sh. The cross-chapter "See also" footers are generated by tools/gen-see-also.pl. Both read the polyrepo source tree, so run them from a checkout that has core/, wit/, and capsules/ as siblings.

Dual-licensed under MIT and Apache 2.0.

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