Troubleshooting
Fixes for specific errors, including Python's ModuleNotFoundError and SSL certificate failures, Docker running out of disk space, and ComfyUI install and out-of-memory problems. Each one starts from the exact error message and shows how to tell which cause you have.
5 articles
uv 0.13 Defaults to Python 3.15: Fix Missing cp315 Wheels and Surprise Source Builds
uv 0.13 downloads Python 3.15 when nothing is pinned. Why torch fails with "no wheels with a matching Python ABI tag (cp315)", why PyYAML silently builds from source, and how to pin.
Docker "No Space Left on Device": Find Which Disk Is Full First
I reproduced the mount, inode and build cases on Docker Desktop and Engine 29, measured where the VM and Mac disks fill up, and found a 966 MB log that docker system df never counted.
Fix ModuleNotFoundError in Python: 6 Causes, 5 Reproduced
ModuleNotFoundError has six distinct causes and reinstalling fixes only one. Five of the six reproduced on macOS with real terminal output (Jupyter and VS Code are sourced from the docs), the command that identifies each, and the fix.
Fix Common ComfyUI Installation and Out-of-Memory Errors
A 2026-current troubleshooting guide for ComfyUI's two most common headaches: install failures (torch/CUDA mismatches, failed custom nodes) and CUDA out-of-memory crashes. Includes copy-paste fixes, and why the once-standard --lowvram flag is mostly a no-op on setups where Dynamic VRAM is actually running — plus how to check whether yours is.
Fix "SSL: CERTIFICATE_VERIFY_FAILED" in Python requests
The SSL: CERTIFICATE_VERIFY_FAILED error in Python requests almost always means your CA bundle can't trust the server's certificate. Here's a cause-first decision tree: identify the cause with one openssl command, then apply the right fix — updating certifi, the macOS certificate script, environment variables, truststore, or a corporate root — without ever turning verification off.