Files
home-network-k3s-impl/decisions
jakman85andClaude Opus 5 d0db63911a
gate / gate (pull_request) Successful in 1m46s
gate / conformance (pull_request) Has been skipped
feat(cilium): roll the agents when cilium-config changes (merged config was silently inert)
A merged Cilium config change did nothing, and everything reported success.
The Hubble flow exporter (#50, merged 2026-10-04) never took effect:

  HelmRelease cilium   Ready=True, "Helm upgrade succeeded ... cilium.v6"
  cilium-config        hubble-export-file-path: stdout  + the allowlist, PRESENT
  cilium agent pods    all three still PRE-MERGE, startTime 2026-10-04T07:11Z
  exported flow lines  0, 0, 0
  Flux                 every Kustomization Ready=True

Cause: the chart's rollOutCiliumPods defaults to false, so Helm rewrites the
ConfigMap and leaves the DaemonSet's pod template untouched -- and cilium-agent
reads that ConfigMap only at STARTUP. Merged, believed delivered, green
everywhere, doing nothing. The same class of failure this repo already guards
against elsewhere: a green signal over something that never ran.

Confirmed by contrast rather than reasoned: the cgroup fix (#42) DID apply --
both the DaemonSet and the running pod mount /sys/fs/cgroup -- because it changed
the POD TEMPLATE, which rolls the DaemonSet on its own. That also explains why
the agents are dated 2026-10-04T07:11Z: that was #42's rollout, and nothing has
rolled them since. The inertness is specific to ConfigMap-only changes.

Set in all three value files to hold the [parity] contract.

Cost, and it is the point: every future Cilium config change now rolls the
agents instead of waiting for a manual restart. Strictly more honest -- it
applies when merged or fails visibly -- but config edits become disruptive by
default. maxUnavailable: 1 bounds it to one node at a time. The lease-holding
node briefly loses the Gateway, PiHole-DNS and Plex VIPs as it cycles, so merge
at a quiet moment.

Merging this IS one rollout (the ConfigMap checksum annotation changes the pod
template) -- which is what finally activates the Hubble exporter.

UNVERIFIED: unreconciled; `filePath: stdout` still unproven and only answerable
after the agents restart (check for flow lines immediately); and the rollout's
actual impact on LAN DNS is unmeasured.

Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>
2026-10-05 21:19:13 -05:00
..

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 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.