(Ruuk shares syntax with F#. A brief introduction to F# is provided here if you need it.)
As a tech lead, I'd set minimum standards for API error handling — every call covers 400, 401, 403, 500. In ticket reviews I'd still find three failure scenarios in the notes and one in the code. Developers had spotted the cases; the language gave them nowhere permanent to put that knowledge.
The knowledge of which errors to handle was always there. It lived in tickets, in team standards, in code comments — and it degraded, because none of those places were connected to the compiler.
I started designing op because I wanted that knowledge to have a durable home in the code itself — a declaration that names every outcome an operation can produce, enforced at every call site. The first article in this series argued that this intent already exists in every codebase — in Javadoc, in JSDoc comments, in OpenAPI response schemas — but lives where the compiler can't see it. op moves it into the declaration.
The Binary Split
