OrthoRoute/.github/instructions/domain-layer.instructions.md

applyTo

applyTo
orthoroute/domain/**

Domain Layer Rules

The domain/ layer is the innermost layer — it must have zero knowledge of infrastructure, frameworks, or KiCad.

Hard Rules

• No infrastructure imports. Never import from orthoroute.infrastructure.* inside domain/.
• No application imports. domain/ cannot import from orthoroute.application.*.
• No KiCad bindings. No pcbnew, kiutils, or any KiCad-specific type anywhere in this layer.
• No I/O. No file reads, network calls, or subprocess usage.

Allowed Dependencies

# ✅ Standard library + pure third-party only
import dataclasses, typing, enum, math
import numpy as np  # pure computation only

# ✅ Within domain
from orthoroute.domain.models.board import Board
from orthoroute.domain.services.routing_engine import RoutingEngine  # abstract base

Patterns

• Models: @dataclass(frozen=True) for value objects; one class per file.
• Services: Abstract base classes (ABCs) only — concrete implementations live in infrastructure/.
• Events: Plain dataclasses, no event bus wiring (bus lives in application/).

When you need external data

Define an interface in application/interfaces/ and inject it via the constructor. Never reach out directly.