Learning Elixir from Claude

A readable companion to the official Elixir documentation, written with Claude.

AI assistants write fluent Elixir. What they get wrong is quieter: code that compiles, reads well and passes the obvious test, then fails under load, on unexpected input, or in a release. This book teaches the concepts and mechanisms you need to spot it. Each chapter has the same shape:

1. Why it exists: the concept
2. The building blocks: the API, condensed
3. How it actually works: what the compiler and runtime do
4. Plausible but wrong: code that looks right and isn't, and the fix
5. Review checklist and sources

Facts are checked against the Elixir 1.20 documentation, and examples were run on Elixir 1.14 and 1.18. Runtime topics shared with Erlang (processes, memory, ETS, distribution, schedulers) are covered in the companion book, Learning Erlang from Claude.

Start with the Introduction; when reviewing code, use the Review Cheat Sheet.

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

#	Chapter	PDF	Markdown
0	Introduction	pdf	md
1	Pattern Matching and Data	pdf	md
2	Errors and Control Flow	pdf	md
3	Processes, Tasks and Agents	pdf	md
4	GenServer	pdf	md
5	Supervision and Registry	pdf	md
6	Enum, Stream and Collections	pdf	md
7	Strings and Unicode	pdf	md
8	Protocols and Behaviours	pdf	md
9	Macros	pdf	md
10	Mix, Configuration and Releases	pdf	md
11	Testing with ExUnit	pdf	md
12	Types	pdf	md
13	Observability	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/01-Pattern-Matching-and-Data.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).