Read the book. It is set to look like a printed page: white ground, one measure, no chrome.
Twenty-seven of the thirty-two chapters are written. Five are reserved and each says so on its own page: chapters 19, 20 and 21 need a benchmark instrument the toolchain does not ship, chapter 25 needs an edition mechanism and a publish client, and chapter 29 needs two collection types to execute on one lane. Chapters 13 and 23 reserve sections for the same kind of reason.
The parts
- Foundations (1–6)
- Hello, wolf. Strings, honestly. Values and expressions. Functions. Collections and generics. Errors are values.
- Memory (7–9)
- Who owns this. Regions, and memory in the shape you meant. The escape hatch as a door.
- Concurrency (10–17)
- Spawning is a scope. Scopes as values. Channels and select. Procs as the unit of failure. Link, monitor, supervision. Region transfer. A failing schedule, replayed.
- Systems (18–25)
- Comptime, one tier and no macros. Perf contracts. Modules and the shape of a project. Packages. The covenant against build scripts.
- Projects (26–32)
- Six programs written twice, and a coda about the allocator you never needed.
The back matter carries a grammar summary, the trap vocabulary, the
diagnostic catalogue, a specification cross-reference, solutions to every
printed exercise, a glossary and an errata page. Section numbers are the page
anchors, so /book/ch08.html#8.4 is a stable link.
How its claims are held
No code appears in the book that CI did not execute. Samples are extracted from the prose and run; console blocks are replayed against the pinned tools and compared byte for byte; a claim about undefined behavior has to be reproduced by both implementations before it can be printed, because one implementation alone is not evidence. A verification lane checks the softer things too: corpus counts, chapter numbering against the table of contents, clause tags, diagnostic codes, and whether every printed exercise has a published solution.
The book is written against a toolchain pin, recorded in the repository. Where the toolchain and the book disagree, the book waits.
Licensing
The code samples are GPL-3.0-or-later with the runtime exception, matching the runtime library, so code you take from the book into your own programs is yours. The license for the prose is proposed as CC BY 4.0 and is not settled; the repository is the authority for both.