# SDD

- [The Spec File as Source of Truth: How to Write Specs That AI Can Actually Implement](https://sdd.sh/2026/05/the-spec-file-as-source-of-truth-how-to-write-specs-that-ai-can-actually-implement.md): Writing specs instead of code is the core premise of SDD — but a bad spec produces bad code just as reliably as a bad prompt does. Here's what separates specs that AI can execute reliably from the ones that waste hours of compute and your afternoon.