What problem does it solve? Stale astroray .pyd files outside the build directory silently shadow fresh builds on sys.path, so tests keep loading an old binary and code changes appear to have no effect. This Skill performs a canonical clean rebuild that finds and removes every shadow copy before compiling. ## Core Features & Use Cases - Shadow detection and removal: Locates every astroray*.pyd on disk, distinguishes legitimate build outputs from shadow copies, and deletes only the shadows after showing the list. - Three build variants: Supports standalone (windows-cpu-vs preset), cuda (windows-cuda-vs preset), and blender (build_blender_addon.py with OpenMP ON and bundled vcomp140.dll). - Post-build verification: Confirms the fresh artifact timestamp and smoke-tests that import astroray resolves inside build/ rather than the project root. - Use Case: A test fix appears to do nothing and failure output is identical to before the edit; run this Skill to clear the stale project-root .pyd, rebuild, and verify the new binary loads. ## Quick Start Ask the assistant to run /rebuild-pyd and specify whether you want the standalone, cuda, or blender variant rebuilt.