Kaappi: A Scheme Programming Language

A book about the Kaappi Scheme implementation, targeting beginners with some programming experience.

Building

Requires XeLaTeX (TeX Live 2024+).

make        # Full build (latexmk resolves TOC/index/refs)
make once   # Single pass (fast iteration)
make view   # Open PDF in default viewer
make clean  # Remove build artifacts

The output is build/kaappi-book.pdf.

Cover

A print-ready wrap cover for the KDP 6"×9" paperback (back cover, spine, and front cover on one full-bleed sheet):

make cover                  # Print-ready PDF → build/cover.pdf
make cover-proof            # Same, with KDP trim/bleed/spine/safe-area guides
make cover-proof PAGES=400  # Proof a hypothetical interior page count
make view-cover             # Build and open

All horizontal geometry derives from \PageCount in cover.tex: the spine width is pages × 0.002252" (KDP's black-&-white-on-white factor), and the sheet width, fold positions, and proofing guides follow. After an interior reflow, update \PageCount, rebuild, and eyeball make cover-proof. A build warning fires if the spine gets too thin for the spine text (below ~0.32", about 142 pages).

The front-cover cup illustration (images/cover-cup.png) was generated with the Gemini API and post-processed with an alpha edge-fade so it blends into the espresso background. To regenerate it:

GEMINI_API_KEY=... python3 scripts/generate-cover-cup.py

Generation is nondeterministic — check that the steam still reads as a clean λ, then rebuild the cover.

Structure

main.tex              Entry point
cover.tex             KDP paperback wrap cover (see Cover above)
preamble/             LaTeX configuration (fonts, layout, styles, listings)
chapters/             Chapter source files
images/               Cover artwork (Gemini-generated cup illustration)
scripts/              Verification and asset-generation scripts
fonts/                Bundled TTF fonts (EB Garamond, Source Sans 3, Fira Code)
build/                Output directory (gitignored)

Fonts

• EB Garamond — body text (serif)
• Source Sans 3 — headings (sans-serif)
• Fira Code — code listings (monospace)

Chapter Outline

Part	Chapters
I: Getting Started	Introduction, Installation, First Steps
II: The Language	Data Types, Lists, Control Flow, Functions, Bindings, Higher-Order Functions, I/O
III: Going Further	Macros, Libraries, Records, Error Handling, Continuations
IV: Beyond R7RS	Standard Library (SRFIs), FFI, Concurrency
Appendices	R7RS Reference, CLI Reference, SRFI Catalog, Error Messages, Ecosystem, Glossary, Further Reading

Related

• Kaappi source — the Scheme implementation in Zig
• kaappi-lang.org — end-user documentation and interactive tour