diff --git a/.claude/memory/rules.md b/.claude/memory/rules.md
index 8d04c551..0dfb8692 100644
--- a/.claude/memory/rules.md
+++ b/.claude/memory/rules.md
@@ -84,3 +84,15 @@ v3 is not part of acceptance. There is no `make test`. Hosted `make` is compile
 - Never assume a running qemu is an orphan; one QEMU at a time; stop with SIGTERM to qemu itself.
 - Read the whole of v3's code before telling Bob what v3 does (rulings have been made on false readings).
 - Record corrections in place, dated, struck not deleted.
+
+## Learned 2026-11-11 (later the same day)
+- **Acceptance runs in the FOREGROUND, one stage per command, check each result before the next.** I first ran
+  the stages with run_in_background and had to stop that run (its log, 20261111-170544, is kept). A stage takes
+  ~2 min here (amd64 build+boot), well inside the 10-minute foreground limit. Use `scripts/nightly.sh accept
+  <amd64|aarch64|riscv64|stick-high>` then `scripts/nightly.sh test-32` -- the same stages the PR gate runs.
+- **Every log and every CSV is evidence and is committed** (Bob: "We track all logs and all CSV's always as
+  evidence") -- passing, failing, stopped runs alike. Commit them together after the run, not mid-run.
+- Empty DoE CSVs (0 bytes) are normal for v4 acceptance boots and are stored as empty files, not LFS pointers.
+- Toolchain for acceptance: `make ARCH=amd64,aarch64,riscv64 init INIT_DOCS=0 INIT_PROOFS=0` (the repo's own).
+- Clean tree: since 90c5c140 a build changes no tracked file (version.h untracked; BLOCK_MAP.md has no
+  timestamp). A *signed* build still rewrites BLOCK_MAP.md's Signed column -- open, Bob's call.