Both render sites (setup's gbrain step and gstack-config gbrain-refresh)
ran `rm -rf` on the LIVE render dir BEFORE invoking gen:skill-docs:user.
Installed skills symlink into that dir (relink prefers it), so one
transient render failure — bun error, disk full, broken template — left
every brain-aware skill's SKILL.md symlink dangling: the whole skill set
vanished from Claude Code until a successful re-render.
Both sites now render into "$RENDER_DIR.tmp.$$" and swap it in only on
SUCCESS via a shared-contract _swap_in_render helper (mv old away, mv tmp
in, drop old — links into the live path stay valid because the path never
changes). The failure branch removes only the tmp dir and says so: the
previous render, and every link into it, stays fully intact. The
deliberate wipe on the gbrain-GONE path (stale render shadowing canonical
files) is unchanged.
Pinned in test/user-render-out-dir-install.test.ts: static shape (render
targets the TMP dir, never the live dir), _swap_in_render driven
behaviorally from BOTH files, and an end-to-end failure-branch fixture
proving a pre-existing render plus an installed symlink survive a failed
render.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
