What problem does it solve? Forked gstack checkouts and gbrain installs break in ways upstream documentation does not cover: fast-forward upgrades fail on diverged branches, Supabase pooler connections drop prepared statements, autopilot daemons wedge, and Windows shims fail. This Skill captures those failure modes and their verified fixes so they are not re-derived every session. ## Core Features & Use Cases - Fork-patch upgrade workflow: Snapshot-then-merge upgrade procedure via gstack-safe-upgrade.sh that protects uncommitted working-tree diffs and unregistered local commits from silent loss. - gbrain failure-mode diagnostics: Numbered fixes for CONNECTION_CLOSED errors, stale sources, wedged autopilot daemons, launchd misconfiguration, and wrong-source query results. - Windows and Claude Desktop setup: gstack-brain-sync.cmd shim installation, LM Studio embedding configuration, and MCP server wrappers for minimal-PATH environments. - Use Case: After a gstack upgrade breaks with merge conflicts on a forked checkout, run the safe-upgrade snapshot and merge workflow, re-apply fork patches, and verify nothing was dropped. ## Quick Start Ask the agent to diagnose why gbrain sync is failing or to run a safe fork-patch upgrade of the local gstack checkout.