Show HN: Kcc, a C compiler built solo with an LLM on $100/mo boot Linux kernel

Cuauhtémoc Pacheco released kcc, a formal C17 compiler written entirely in ARM64 assembly as a single literate program using the weft metalanguage, co-authored with an AI collaborator (Claude) on a $100/month budget. The compiler checks C against the Standard, optimizes, allocates registers, emits native machine code, self-compiles to a byte-identical binary, cross-compiles to x86-64 on Linux and macOS, builds and runs Lua, SQLite and DOOM, and boots a Linux kernel. The roughly 1000-page book kcc.pdf is committed to the repository under an MIT license and is published as a GitLab Release asset.

kcc is a formal C17 compiler written entirely in ARM64 assembly, and set down as a single literate program using weft https://github.com/temo-pacheco/weft , a metalanguage built to be authored and read by human and AI collaborators alike. Every instruction is explained in prose before it is written in code. It checks C against the Standard, optimises it, allocates registers, and emits native machine code; it compiles itself to a byte-identical binary; and it cross-compiles to x86-64 Linux and macOS . It builds and runs Lua, SQLite, and DOOM — and boots a Linux kernel. The whole book is the compiler ≈1000 pages : read kcc.pdf https://github.com/LiterateDrivenDevelopment/kcc/blob/main/kcc.pdf in this repository, also published on Releases https://gitlab.polinesso.org/literate-programming/kcc/-/releases , or build it yourself see below . Learn more about Literate Driven Development at https://literatedriven.com https://literatedriven.com . Everything the machine builds — the assembly modules, the verification scripts, and the Makefile itself — is generated by tangling the literate sources. You never edit generated files; you edit the book. kcc.weft master document LaTeX preamble + @i includes literate/ all the chapters prose + code fragments assets/ cover art SVG → the PDF covers kcc.pdf the typeset book committed; rebuilt with make pdf README.md this file LICENSE MIT The typeset book, kcc.pdf , is committed, so the repository always carries a readable copy of the current text. Rebuild it with make pdf . There is a one-time bootstrap: because the Makefile is itself tangled from the book, you generate it first, then use it. 1. Tangle sources, scripts, and the Makefile into gen/ and ./Makefile . weft -p gen/ --mkdirs kcc.weft 2. Build the compiler gen/kcc . make 3. Compile something with it. ./gen/kcc gen/hello.c -o gen/hello && ./gen/hello -p gen/ prepends gen/ to every tangle output; --mkdirs creates the directories. The generated tree lives entirely under gen/ plus the root Makefile ; make clean removes it and the command above regenerates it. | Target | What it does | |---|---| | make / make build | assemble + link gen/kcc | | make difftest | compile a corpus with kcc and clang, compare | | make diagtest / make warntest | invalid programs are rejected; -Wall warns | | make test-codegen / make e2e / make interop | run generated programs | | make selfhost- | recompile a module in C with kcc, relink, verify | | make meta-c | full self-host fixpoint on Linux needs Docker + qemu | | make ci | the complete verification suite | | make pdf | weave the book and typeset kcc.pdf | The verification scripts locate their own base directory, so they work under any -p prefix. make pdf weaves the .weft sources to kcc.tex and typesets kcc.pdf with LuaLaTeX. The covers are regenerated from assets/ .svg when rsvg-convert is available. The resulting kcc.pdf is committed alongside the sources, so the book can be read straight from the repository; tagged versions are also published as a Release asset on GitLab. - weft ≥2.0.0 the literate tool . - A C toolchain's as and ld Xcode command-line tools on macOS . - For the book: a TeX distribution with LuaLaTeX and latexmk — a full TeX Live https://tug.org/texlive/ , or the lightweight TinyTeX https://yihui.org/tinytex/ a minimal TeX Live — and, optionally, rsvg-convert for the covers. - For make meta-c and the kernel-boot reproduction: Docker and qemu-user. MIT — see LICENSE https://github.com/LiterateDrivenDevelopment/kcc/blob/main/LICENSE . Copyright © 2026 Cuauhtémoc Pacheco, co-authored with an AI collaborator Claude .