AI assistance disclosure: This article was drafted with the help of Claude. All technical content, design decisions, code references, and screenshots reflect production systems I designed and operate at airCloset; the prose was revised by me prior to publication. Hi, I'm Ryan , CTO at airCloset. We've migrated our GitHub Actions runners twice: GitHub-hosted to Blacksmith, then Blacksmith to Namespace . The results, up front: Per-run CI cost is roughly a quarter of what we paid on...