---
name: delegate-build-preflight-hang
description: Background build agents hang on full spt-daemon integration suite — use targeted unit preflight only
metadata: 
  node_type: memory
  type: feedback
  originSessionId: a1129c8b-f417-4996-b578-16834dc33944
---

Delegate-then-gate pattern works well (M11 session: D/B/A/E/docs all built by bg agents, all verified clean). BUT full `spt-daemon`/`spt` integration suite hangs silently in preflight (~1h, no completion signal — Feature B agent confirmed).

**Why:** Integration suite is slow/blocking in the bg agent environment; targeted unit sweeps run in ~8s.

**How to apply:** When delegating builds, instruct targeted unit preflight only (`cargo test -p spt-X lib`, specific test names). Never instruct the full integration suite in bg agent context. Check agent liveness via transcript mtime, not by Reading it.