Built a tiny interpreter from scratch in C to understand how they work
Details
- External ID
- 45905983
- Source
- HN
- Company
- —
- Product
- Built a tiny interpreter from scratch in C to understand how they work
- Website domain
- github.com
- Launched
- Nov. 12, 2025
- Cohort
- —
- Upvotes
- 5
- Upvotes percentile
- 0.0982532751091703
- Tags
- —
- Fetched at
- Sept. 7, 2026, 9:25 p.m.
- Updated at
- Sept. 7, 2026, 9:25 p.m.
Description
Hi HN, I'm the author.I built this project for two simple reasons: I've always used higher-level languages and wanted to finally understand what's happening "under the hood" of an interpreter. I also wanted a real project to force me to "power up" my C skills, especially with manual memory management and reference counting.The result is ToyForth, a minimal interpreter for a Forth-like language, written from scratch in C, stack-based.I focused on making the code clean and understandable. It's broken down into a few simple parts:A parser that turns source text into a list of objects (parser.c).A small stack-based virtual machine (main.c).A manual reference counting system (incRef/decRef) to manage object memory (mem.c) and so on.My main goal was learning, but I've tried to document it well in the README.md so it could be a "starter kit" for anyone else who wants to learn by reading a small, complete implementation.It's easy to try out. I'd genuinely appreciate any feedback on my approach or my C code.Here's the link: https://github.com/renvins/toyforth-interpreter
Enrichment
- Theme
- developer tools and programming utilities
- Vertical
- Horizontal
- Function
- Dev tools
- Audience
- Developer
- AI stance
- Not AI
- Project type
- Hobby / open-source project
- Normalized one-liner
- educational interpreter written in c
- Manually corrected
- False
Could you build this?
Partial While AI can generate textbook lexers and recursive-descent parsers in C, writing a robust C interpreter with proper manual memory management and AST evaluation requires solid systems programming fundamentals to avoid memory leaks and segmentation faults.
What it would actually take: A C interpreter requires a lexer, a Pratt or recursive descent parser, an AST definition, an environment/symbol table, an evaluator, and custom memory management (such as an arena allocator or mark-and-sweep garbage collector). Specialized knowledge of compiler design and C memory safety is required to build a reliable implementation.
Discussion
1 comment analyzed.
Competitors
Other products that read as similar to this one — 117 launches clear the similarity bar, closest 8 shown.
Attention rank: #118 of 118 (itself plus its competitors, highest first — normalized so YC and Product Hunt are compared fairly).
Launched 12 days after the earliest competitor.
- I wrote a minimal memory allocator in C · hn · 2025-11-23 · 137 upvotes · similarity 0.57
- CJIT, a single-binary C compiler that can self host · hn · 2026-04-13 · 7 upvotes · similarity 0.52
- C/C++ Cheatsheet · hn · 2026-01-23 · 10 upvotes · similarity 0.48
- SHDL · hn · 2026-01-28 · 48 upvotes · similarity 0.48
- Cicada · hn · 2026-01-30 · 57 upvotes · similarity 0.48
- Ced · hn · 2026-05-07 · 5 upvotes · similarity 0.47
- Cj–tiny no-deps JIT in C for x86-64 and ARM64 · hn · 2025-11-05 · 21 upvotes · similarity 0.45
- I Made a Programming Language with Python Syntax, zero-copy and C-Speed · hn · 2026-02-18 · 10 upvotes · similarity 0.45
Other launches for this product
- No other launches for this product.
Same idea, different domain
Nobody's really built a dev tools tool for Sales yet.