This directory owns physical-design integration, managed technology inputs, smoke implementation-flow sources, and the self-developed commercial-flow drivers.

pdk/ contains the locked PDK setup helpers and managed PDK checkouts.
smoke/syn/ contains Yosys synthesis and source-export integration.
smoke/sta/ contains OpenSTA constraints and timing integration.
librelane/ contains the open-source IHP130 core-hardening and full-chip pad-ring flows.
ecc/ contains the open-source ICS55 padless-core hardening flow backed by the locked ECOS Chip Compiler release.
commercial/ contains licensed-tool orchestration and flow logic. PDKs, foundry decks, commercial libraries, site configuration, and results remain outside Git.
sdf/, when supplied by an implementation flow, contains post-layout netlist and SDF collateral consumed by post-layout simulation.

The local Makefile is reserved for implementation flows that require the selected PDK, technology collateral, and often site-specific tools.

Generated layout, report, and database outputs must remain outside tracked source paths. Treat PDK-dependent physical-design results as toolchain-specific evidence and record the selected profile, PDK, and validation command when handing off a change. See Engineering Workflow.