CI deployed every Steam game from scratch on each run, downloading the whole game from Steam each time. scripts/boot-test.sh now runs the new `gbrgames boot-test ID`, the builder's own deploy path: the same payload and node-agent BootTest, but Steam games start from the cache volume (gbr-steamcache-<app>, kept by RUNNER.md's prune). The cache is updated at most once a day (a timestamp in the cache volume, not copied into servers), so a repeat run within a day doesn't ask Steam for an update at all; the node-agent's own install still checks the files and fetches anything newer. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>