Show HN: Yass – Yet Another Spec Syntax Enters Beta

Developer shakefu released Yass, a specification syntax that uses RFC2119 keywords in a minimal YAML format, entering public beta. The Yass CLI was validated across 7 languages — TypeScript, Python, Go, C, C++, Erlang and Elixir — producing byte-exact output in sandboxed Claude Code harnesses using Opus 4.6, according to the project's Show HN post. The tool is designed so an agent can read the shakefu/yass repo README and proceed without further instruction.

This has been a side project for a while but it’s finally ready for public Beta. Tl;dr: Yass leverages RFC2119 keywords in a minimal Yaml format, relying on trained in behaviors for those keywords to provide strong model behaviors. The yass CLI itself is all that you need - simply tell an Agent to look at the shakefu/yass repo README and they get all the information needed to proceed. This was validated with hundreds of experiments and trials against different models and platforms. The most significant of which was a single Yass spec tree reproduced byte-exact output Yass CLI implementations across 7 different languages TypeScript, Python, Go, C, C++, Erlang and Elixir in sandboxed Claude Code harnesses using Opus 4.6, rather than expensive frontiers. Give it a try, open GH issues if you find things that aren’t working or make your agent open them , or if you have feature requests. Enjoy Comments URL: https://news.ycombinator.com/item?id=49812577 https://news.ycombinator.com/item?id=49812577 Points: 1 Comments: 1