Two bugs in require_docker: 1. apt post-install hooks (needrestart etc.) block on stdin which is at EOF when running via pipe; DEBIAN_FRONTEND=noninteractive skips them 2. bash's command hash table doesn't pick up a newly installed binary; hash -r flushes it so command -v docker finds /usr/bin/docker Also moved usermod and success log after the binary check so [OK] only prints when docker is actually reachable. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01LQJBvqzXeyuhhAcAA3Q5Wq