Domain Layer Module

The domain layer (primarily src/atopile/build_steps.py and src/faebryk/exporters/) encompasses the logic and processes specific to electronic hardware engineering. This includes the build pipeline that transforms a compiled graph into manufacturing artifacts (Gerbers, BOMs, Pick & Place).

Quick Start

Run the standard build pipeline from a project directory (where ato.yaml lives):

ato build

Relevant Files

• Build Orchestration: src/atopile/build_steps.py
  • Defines the Muster class (a DAG-based task runner).
  • Registers standard build targets: generate_bom, generate_manufacturing_data, update_pcb, etc.
• Build entry / app init: src/atopile/build.py (constructs app graph from .ato or .py, runs unit inference)
• Exporters: src/faebryk/exporters/
  • pcb/: KiCad PCB generation and layout sync (layout_sync.py).
  • bom/: Bill of Materials generation (jlcpcb.py, etc.).
  • netlist/: Netlist formatting.
  • documentation/: Datasheets, diagrams.
• Layout sync inputs:
  • src/atopile/layout.py (generates .layouts.json module→layout mapping)
  • src/atopile/kicad_plugin/README.md (plugin workflow overview)

Dependants (Call Sites)

• CLI (src/atopile/cli/build.py): The ato build command directly invokes build_steps.muster to execute the pipeline.
• IDE/Extension: May invoke specific build steps for previews (e.g., generate_3d_render).

How to Work With / Develop / Test

Core Concepts

• Muster: The task runner. Targets declare dependencies (e.g. generate_bom depends on build_design).
• Layout Sync: The process of preserving manual PCB layout changes while updating the netlist/components from the code (update_pcb).
• Artifacts: Files produced by the build process, stored in the build directory.

Development Workflow

1. Adding a Config Option: If a new build step needs configuration, add it to atopile.config (not covered here, but relevant).
2. New Exporters: Create a new module in src/faebryk/exporters/ and register a wrapper function in build_steps.py using @muster.register.

Testing

• Integration Tests: Since this layer orchestrates the whole flow, it is best tested via end-to-end tests or integration tests in test/end_to_end/ or test/integration/.
• Manual Verification: Run ato build on a sample project and inspect the generated artifacts (Gerbers, BOM csv).
• Muster unit tests: ato dev test --llm test/test_muster.py -q

Best Practices

• Idempotency: Build steps should generally be idempotent.
• Virtual Targets: Use virtual=True for targets that just group other targets (e.g. all or default).
• Layout Preservation: Be extremely careful when modifying update_pcb or layout_sync logic to avoid dataloss of user’s manual PCB routing.