Learning Erlang from Claude

A readable companion to the official Erlang/OTP documentation, written with Claude.

With AI assistants writing more of the code, the valuable knowledge is less about syntax and more about concepts and how the runtime actually behaves — the details you need to judge whether plausible-looking code is right. Each chapter has the same shape:

1. Why it exists — the concept
2. The building blocks — the API, condensed
3. How the runtime actually does it — mechanics from the Reference Manual and Efficiency Guide
4. Plausible but wrong — code that compiles and passes a happy-path test, and why it fails
5. Review checklist and sources

All chapters were checked against the OTP 29.1.1 documentation. Start with the Introduction; when reviewing code, use the Review Cheat Sheet.

Companion book: Learning Elixir from Claude covers what Elixir adds on top of the runtime: pattern matching, GenServer and Task, supervision with Registry, macros, Mix and releases, ExUnit, types and telemetry.

Whole book in one PDF: Erlang book, all chapters, with a table of contents.

#	Chapter	PDF	Markdown
0	Introduction	pdf	md
1	Supervision Trees	pdf	md
2	Processes and Mailboxes	pdf	md
3	Binaries and Memory	pdf	md
4	ETS	pdf	md
5	gen_server and gen_statem	pdf	md
6	Distribution	pdf	md
7	Applications and Releases	pdf	md
8	Testing	pdf	md
9	Observability	pdf	md
10	Schedulers and Performance	pdf	md
11	NIFs and Ports	pdf	md
12	Elixir Alongside Erlang	pdf	md
13	gen_statem in Depth	pdf	md
14	Review Cheat Sheet	pdf	md

Rebuilding the PDFs

Edit the Markdown in md/, then run tools/build.sh (all chapters) or tools/build.sh md/04-ETS.md (one chapter). It needs pandoc and Chromium or Chrome; set CHROME=/path/to/chrome if it isn't found automatically.

To rebuild the combined book, run tools/build_book.py (same requirements).