What is architecture.hexum?

Last updated 29 August 2026

architecture.hexum
skill full

layer ui
  match src/ui/**
  match src/pages/**

layer services
  match src/services/**

layer data
  match src/data/**

rule no_ui_to_data
  from ui
  cannot use data
  severity high
  message UI must not import data access directly.
  hint Call services instead.

Full field table: architecture.hexum in the docs. Check: hexum_check architecture linter for AI coding agents.

FAQ

What is architecture.hexum?

A file in the repo. Layers group files. Rules say a layer cannot use another. hexum_check reads it. Also accepted: hexum.hexum, .hexum, or the first *.hexum in the root. Guide: /architecture-hexum.

Is hexum_check an LLM?

No. hexum_check is deterministic. It maps files to layers in architecture.hexum and reports forbidden imports. It does not call a model.

What is Hexum?

Hexum is an MCP server for Cursor, Claude Code, and other coding agents. It sits between the agent and the model: hexum_shrink sends this turn instead of the repository, hexum_check fails the turn when architecture.hexum is broken, and you keep your editor. On MBPP, context dropped about 85% with the same tests passing.