jakman85andClaude Opus 5
ef8ef5ac29
The first real run failed on all three nodes: fatal: [k3s-prod-1]: "No package matching 'update-notifier-common' is available" update-notifier-common is an UBUNTU package and does not exist in Debian -- `apt-cache policy` returns Candidate: (none) on trixie. The role asserted it "owns the hook that creates /var/run/reboot-required", which is true on Ubuntu and false here, so the role could never have worked. Three further measurements settled the replacement: notify-reboot-required is absent; NO linux-image-* postinst references it (invoking it is an Ubuntu patch, so dropping a script at that path would never be called); and no hook under apt.conf.d or /etc/kernel mentions reboot-required. Debian trixie ships no mechanism at all. So the role now provides it: * /usr/local/sbin/k3s-notify-reboot-required -- touches the sentinel when the running kernel is not the newest installed, using `linux-version` (from linux-base, a dependency of every linux-image, measured present) because kernel version ordering is not string ordering. * /etc/apt/apt.conf.d/99-k3s-reboot-required -- DPkg::Post-Invoke, `|| true` so it can never abort an apt transaction. /run is tmpfs (measured), so the sentinel self-clears on boot; no cleanup task. The verify assert was ALSO weaker than it looked: a `find` glob for *update-notifier* / *unattended-upgrades* under apt.conf.d would have matched Debian's own unattended-upgrades conffile and reported "writer present" while none existed. It now stats the two exact paths this role owns and requires the script to be executable. Newly verified: the script ran on prod-1 as unprivileged k3s under sh -x -- running=newest=7.1.8+deb13-amd64, took the equal branch, exited 0, wrote nothing. Correct. sh -n and bash -n clean. Still unverified: the WRITING half never executes while running == newest, so the sentinel has not been seen created and kured has not been seen react. The honest test is the next kernel upgrade. Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>
decisions/ — the handoff log, one file per entry
This directory is the decision log. ../DECISIONS-LOG.md is the frozen archive of
everything written before 2026-09-29 and is never edited again (see "The archive is
frozen" below).
Why this exists
DECISIONS-LOG.md was append-only in a single file, and every agent appended to its
tail. Two branches that both append hit the same last hunk, so git cannot
auto-merge them: the second one to be reviewed conflicts, and so does the third, and
the fourth. Measured on 2026-09-29: four of the five open PRs were unmergeable, and
DECISIONS-LOG.md was the only conflicting file in all four:
#22 fix/crafty-oauth2-proxy-signin CONFLICT (content): DECISIONS-LOG.md
#20 feat/conformance-job-template CONFLICT (content): DECISIONS-LOG.md
#19 feat/conformance-trigger-kubeconfig CONFLICT (content): DECISIONS-LOG.md
#18 feat/conformance-runner-image CONFLICT (content): DECISIONS-LOG.md
#17 feat/ci-is-the-approver clean (it touched no log entry)
Nothing was wrong with any of those changes. The log's storage format serialised work that was otherwise parallel, and it got worse with every concurrent branch: N branches produce N-1 rebases, each of which invalidates any gate run that preceded it.
The fix is the obvious one for concurrent appenders: stop sharing a file. Each
handoff is its own file. Two agents writing handoffs touch disjoint paths, so there is
nothing for git to merge and nothing to conflict. This scales to any number of parallel
branches with zero coordination — which is the point, since the agents are deliberately
isolated from each other in separate worktrees (required by CLAUDE.md §0) and cannot
coordinate.
There is deliberately no index file and no counter. An index would be a shared
mutable file — exactly the thing that just failed — and a sequence number would have
two agents racing for 0043. The directory listing is the index.
Writing an entry
One file per handoff, named:
decisions/YYYY-MM-DD-<slug>.md
<slug> is lowercase [a-z0-9-]. Use your branch name's last segment — it is
already unique per unit of work, which is precisely the property the filename needs.
A branch fix/crafty-oauth2-proxy-signin handed off on 2026-09-29 writes:
decisions/2026-09-29-crafty-oauth2-proxy-signin.md
The file is YAML frontmatter followed by three required sections:
---
date: 2026-09-29
branch: fix/crafty-oauth2-proxy-signin
title: The Keycloak gate works — Crafty's own login was the wall
---
## What changed
Prose. What you actually did, and why.
## What I verified
The measurements, with their numbers. Quote the field you read, not the prose you
believed. Name the gate result and its exit code.
## What I did NOT verify
Everything else. An honest "UNVERIFIED" is worth more than an optimistic "green" —
this repo has been burned by the difference more than once.
All three headings are required and enforced (ci/decisions-log.sh). They are
CLAUDE.md §7's contract; making them a checked structure is what stops an entry
degrading into "done ✅".
Reading the log
The whole log, oldest first:
ls decisions/[0-9]*.md | sort
The current PM handoff — the newest entry. Ties within a day are broken by what landed
on main last, which is the honest answer, so ask git rather than the filename:
git log --diff-filter=A --format='%H' --name-only -- 'decisions/[0-9]*.md' \
| grep '^decisions/' | head -1
For a quick skim of who said what:
grep -H '^title:' decisions/[0-9]*.md | sort
The archive is frozen
DECISIONS-LOG.md is read-only history. Its SHA-256 is pinned in
decisions/ARCHIVE.sha256 and ci/decisions-log.sh fails the merge gate if the file
changes. That is not ceremony: without it, the next agent to read runbooks/ or an old
CLAUDE.md habit appends to the tail again and re-creates the conflict for everybody
else, silently, one PR at a time.
If the archive genuinely must change (a leaked credential to redact, say), that is a
deliberate, reviewed act: change it, run sha256sum DECISIONS-LOG.md > decisions/ARCHIVE.sha256,
and say in your handoff entry why. Re-pinning is visible in the diff. Appending is not.