Phoenix File Uploads

Use this skill before implementing ANY file upload functionality.

RULES — Follow these with no exceptions

1. Use manual uploads (NOT auto_upload: true) for form submission patterns
2. Always add upload directory to static_paths() — files won't be accessible without this
3. Handle upload errors — display error_to_string/1 output in templates
4. Validate file types server-side — never trust client MIME types
5. Restart server after changing static_paths() — changes don't apply until restart

Implementation Workflow

Follow these steps in order: