FabLL — Node API и граф типов в faebryk

engineering

fabll is a Claude Code skill that explains how the `faebryk.core.node` module (FabLL) maps Python node and trait class declarations into the TypeGraph and instance graph. It covers the field system, type invariants enforced at class-creation time, type registration via `Node._register_type`, and the instantiation lifecycle using `bind_typegraph` / `create_instance`. Key source files are `src/faebryk/core/node.py`, `faebrykpy.py`, and `graph.py`; core tests run with `ato dev test --llm test/core/test_node.py` and `test/library/test_traits.py`. Use this skill when defining new hardware components or traits in faebryk, working with the Node API, or diagnosing why FabLL enforces single-level subclassing for node types.