devdisk is a single dependency-free Python file that scans for the space developer tools quietly eat: npm/pnpm/yarn/pip/uv/Homebrew caches, node_modules, Rust target dirs, Xcode DerivedData, Gradle, Ollama and Hugging Face models. Strictly read-only: writes a local HTML report and a cleanup script you inspect. macOS, Linux, Windows. Cleanup guides at disk.sadana.app/guides/. Free, no telemetry.
Dev caches quietly fill disks and it is hard to know what is safe to delete. I wanted a read-only scanner that explains what it finds and never deletes anything itself.