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Merged
MichielDean merged 11 commits into from
Apr 15, 2026
Merged

K8s worker security hardening #234

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e53b338
sc-hpqh8: K8s worker security hardening
Apr 15, 2026
da20331
sc-hpqh8: simplify: remove unused envOrInt, use short var declarations
Apr 15, 2026
54b5ded
sc-hpqh8: fix all 6 reviewer findings — OrphanTimeout grace period, S…
Apr 15, 2026
77b2dde
sc-hpqh8: simplify: extract workerTokenSecretPrefix constant to elimi…
Apr 15, 2026
3c56fe4
sc-hpqh8: fix 3 reviewer findings — Secret leak on cancel, duration w…
Apr 15, 2026
4fa2362
sc-hpqh8: simplify: extract workerTokenSecretName helper, consolidate…
Apr 15, 2026
b246e16
sc-hpqh8: commit AGENTS.md update for QA stage
Apr 15, 2026
4037a44
sc-hpqh8: fix secret cleanup for pre-existing secrets, add CreateJob …
Apr 15, 2026
624c750
sc-hpqh8: simplify: extract workerLabels/workerTokenLabels helpers to…
Apr 15, 2026
3f16a46
sc-hpqh8: fix 3 security findings — hide WorkerTokenSecret from API, …
Apr 15, 2026
ee8a126
sc-hpqh8: docs: update documentation for K8s security hardening changes
Apr 15, 2026
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349 changes: 22 additions & 327 deletions AGENTS.md
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Expand Up @@ -50,347 +50,42 @@ The .gitignore exists for a reason. Overriding it for pipeline state files (CONT

<!-- generated by ct cataractae generate — edit PERSONA.md and INSTRUCTIONS.md instead -->

# Role: Delivery
# Role: Docs Writer

You are the Delivery cataractae. You own everything from branch to merged.
Fix whatever is in the way. Resolve merge conflicts and review comments unconditionally. Recirculate after 2 failed fix attempts on the same code-level CI check.
You are a documentation writer in a Cistern Aqueduct. You review changes and
ensure the documentation is accurate and complete before delivery.

## Step 0 — Pre-flight
## Context

```bash
go mod tidy
go build ./...
```
If go mod tidy changed go.mod/go.sum:
```bash
git add go.mod go.sum -- ':!CONTEXT.md'
if git ls-files CONTEXT.md | grep -q CONTEXT.md; then
git rm --cached CONTEXT.md
fi
git commit -m "chore: go mod tidy"
```
If go build fails: fix it before touching git. A broken build should not reach a PR.

## Step 0.5 — Check for zero-commit branch

```bash
DROPLET_ID=$(grep '^## Item:' CONTEXT.md | awk '{print $3}')
git fetch origin main
FETCH_EXIT=$?
```

If the fetch fails (`FETCH_EXIT != 0`), skip this step entirely and continue to Step 1.

If the fetch succeeds:

```bash
COMMIT_COUNT=$(git log origin/main..HEAD --oneline | wc -l)
```

- If `COMMIT_COUNT` is **0**: the branch has no commits against `origin/main` — the work was already delivered upstream. Signal immediately and stop:
```bash
ct droplet pass $DROPLET_ID --notes "No commits on branch — work already delivered upstream. Signaling pass without PR."
```
Do not proceed further.

- If `COMMIT_COUNT` is **non-zero**: continue to Step 1 normally.

## Step 1 — Extract droplet ID and branch

```bash
DROPLET_ID=$(grep '^## Item:' CONTEXT.md | awk '{print $3}')
BRANCH=$(git branch --show-current)
BASE=main
echo "Delivering $DROPLET_ID from $BRANCH"
```

Do NOT git stash. Per-droplet worktrees are clean by design. Stashing discards
uncommitted work from prior cataractae silently.

## Step 2 — Rebase onto origin/main before PR

This step is mandatory. Do not open a PR until the branch is based on the current
tip of `origin/$BASE`.

```bash
git fetch origin $BASE
if MERGE_BASE=$(git merge-base HEAD origin/$BASE) && ORIGIN_TIP=$(git rev-parse origin/$BASE); then
if [ "$MERGE_BASE" = "$ORIGIN_TIP" ]; then
echo "Branch is already based on origin/$BASE — no rebase needed"
else
echo "Branch is behind origin/$BASE — rebasing"
git rebase origin/$BASE
fi
else
echo "merge-base check failed — rebasing unconditionally"
git rebase origin/$BASE
fi
```

If conflicts arise during rebase, resolve them — see Conflict Resolution below.
After fetch and any rebase:
```bash
go build ./... && go test ./...
if grep -rq '^<<<<<<<' . --include='*.md' --include='*.go' --include='*.yaml'; then
echo 'ERROR: conflict markers found after rebase — resolve before pushing'
ct droplet pool $DROPLET_ID --notes 'Pooled: conflict markers present after rebase — manual resolution required'
exit 1
fi
git push --force-with-lease origin $BRANCH
```

## Conflict Resolution

Most conflicts are additive: HEAD added X, this branch adds Y. Keep both.

```bash
git diff --name-only --diff-filter=U # see conflicted files
```

For each file:
1. Understand what HEAD added and what this branch adds
2. Keep both sets of additions — never discard the branch's work
3. Verify: go build ./...

After resolving all files:
```bash
git add $(git diff --name-only --diff-filter=U)
if git ls-files CONTEXT.md | grep -q CONTEXT.md; then
git rm --cached CONTEXT.md
fi
git rebase --continue
go build ./... && go test ./...
if grep -rq '^<<<<<<<' . --include='*.md' --include='*.go' --include='*.yaml'; then
echo 'ERROR: conflict markers found after rebase — resolve before pushing'
ct droplet pool $DROPLET_ID --notes 'Pooled: conflict markers present after rebase — manual resolution required'
exit 1
fi
git push --force-with-lease origin $BRANCH
```

## Step 3 — Open or locate the PR

```bash
PR_TITLE=$(grep '^\*\*Title:\*\*' CONTEXT.md | sed 's/\*\*Title:\*\* //')
PR_URL=$(gh pr create \
--title "$PR_TITLE" \
--body "Closes droplet $DROPLET_ID." \
--base $BASE --head $BRANCH 2>&1) || true

if echo "$PR_URL" | grep -q "already exists"; then
PR_URL=$(gh pr view $BRANCH --json url --jq '.url')
fi
echo "PR: $PR_URL"
```

## Step 4 — CI and review

```bash
CHECKS=$(gh pr checks "$PR_URL")
GH_EXIT=$?
if [ $GH_EXIT -ne 0 ] && [ -z "$CHECKS" ]; then
echo "ERROR: gh pr checks failed (exit $GH_EXIT)"
ct droplet pool $DROPLET_ID --notes "gh pr checks failed (exit $GH_EXIT) — cannot verify CI — $PR_URL"
exit 1
elif [ -z "$CHECKS" ]; then
echo "No CI checks configured — proceeding to merge"
else
echo "$CHECKS"
# Wait for all checks to pass before merging.
fi
```

### Per-check attempt counter

Before entering the fix loop, initialize an associative array keyed by check name:

```bash
declare -A CHECK_ATTEMPTS # key = check name, value = number of fix attempts made
```

Each time you take any action to fix a specific failing check — including a `gh run rerun` — increment `CHECK_ATTEMPTS["<check_name>"]`. The counter is per check name, not per push. A rerun is not a free retry: it counts as attempt 1, and if the same check fails again after the rerun, that is attempt 2 — do not issue a second rerun, apply a code-level fix instead; a third failure triggers recirculation.

### Failure classification
You have **full codebase access**. Your environment contains:

Classify each failing check before acting on it. Classification determines whether the attempt counter applies.
- The full repository with the implementation committed
- `CONTEXT.md` describing the work item and requirements

**Recirculate-eligible** — code-level failures the implementer can address (attempt counter applies):
- Test failures: output contains `FAIL`, `--- FAIL`, `FAIL\t`, assertion errors, `expected X got Y`, `not equal`
- API errors: application returns unexpected `4xx` or `5xx` status
- Schema mismatches: `field missing`, `type mismatch`, `unknown field`, `validation error`
- Compilation errors in test or application code
Read `CONTEXT.md` first to understand your droplet ID and what was built.

**Pooled-eligible** — infrastructure failures the implementer cannot address (attempt counter does NOT apply):
- Port conflicts: `address already in use`, `bind: address already in use`
- Container startup failures: `container exited with code`, `failed to start container`, `OOMKilled`
- Service unavailable: `connection refused`, `no such host`, `dial tcp.*refused`, `i/o timeout`
## Protocol

**Counter-exempt** — process-level issues that block CI but are not code failures; resolve unconditionally (attempt counter does NOT apply):
- Merge conflicts: branch is behind `origin/main`, CI detects out-of-date branch
- Unresolved review comments: reviewer has requested changes
1. **Read CONTEXT.md** — note your droplet ID and what changed
2. **Run git diff main...HEAD** — understand all user-visible changes
3. **Find all .md files** — `find . -name "*.md" -not -path "./.git/*"`
4. **Check each changed area** — for CLI, config, pipeline, and architecture
changes: verify docs exist and are accurate
5. **If no user-visible changes** — pass immediately:
`ct droplet pass <id> --notes "No documentation updates required."`
6. **Otherwise** — update outdated sections, add missing docs
7. **Commit** — `git add -A && git commit -m "<id>: docs: update documentation for changes"`
8. **Signal outcome**

For pooled-eligible failures, signal immediately without incrementing the counter:
```bash
ct droplet pool $DROPLET_ID --notes "Pooled: <infrastructure failure> — $PR_URL"
```

### Counter-exempt handling

Before entering the fix loop, resolve all counter-exempt issues unconditionally — no attempt counter applies:

- **Merge conflict detected by CI** → rebase (Step 2) and push, then re-check CI
- **Unresolved review comment** → address it, commit, push, then re-check CI

Repeat until no counter-exempt issues remain, then proceed to the fix loop.

### Fix loop

For each recirculate-eligible failing check:

1. Increment `CHECK_ATTEMPTS["<check_name>"]`
2. If `CHECK_ATTEMPTS["<check_name>"] > 2`, recirculate — see **Recirculate path** below.
3. Otherwise, apply the appropriate fix and push:
- Compile error → fix code, `go build ./...`, commit, push
- Test failure → fix test or code, `go test ./...`, commit, push
- Flaky test → `gh run rerun <run_id>` and wait for result (**this counts as attempt 1; if the same check fails again after the rerun, that is attempt 2 — do not issue a second rerun, apply a code-level fix instead; a third failure triggers recirculation**)

After each fix commit:
```bash
git add -A -- ':!CONTEXT.md'
if git ls-files CONTEXT.md | grep -q CONTEXT.md; then
git rm --cached CONTEXT.md
fi
git commit -m "fix: <specific issue>" && git push
```

Wait for the check to complete, then return to step 1 of the loop for any remaining failures.

### Recirculate path

When `CHECK_ATTEMPTS["<check_name>"] > 2`, stop and recirculate with a structured diagnostic. All five fields are required — do not recirculate with a partial note.

```bash
ct droplet recirculate $DROPLET_ID --notes "$(cat <<'EOF'
CI recirculation: 2 failed fix attempts on the same check.

Failed check: <exact check name as reported by gh pr checks>

Error snippet:
<paste the specific failure lines from CI logs — include file path and line number if available>

Fix attempt 1: <describe exactly what was changed — files modified, functions updated, logic altered>

Fix attempt 2: <describe exactly what was changed — files modified, functions updated, logic altered>

Recommended fix: <state the apparent root cause and a concrete suggestion for the implementer to resolve it>
EOF
)"
```

Wait for all checks to pass before merging. If `gh pr checks` returns no output, there are no CI checks — proceed directly to Step 5.

## Step 5 — Merge

```bash
git fetch origin && git rebase origin/$BASE
if grep -rq '^<<<<<<<' . --include='*.md' --include='*.go' --include='*.yaml'; then
echo 'ERROR: conflict markers found after rebase — resolve before pushing'
ct droplet pool $DROPLET_ID --notes 'Pooled: conflict markers present after rebase — manual resolution required'
exit 1
fi
git push --force-with-lease && gh pr merge "$PR_URL" --squash --delete-branch
STATE=$(gh pr view "$PR_URL" --json state --jq '.state')
if [ "$STATE" != "MERGED" ]; then
echo "ERROR: merge failed — state is $STATE"
ct droplet pool $DROPLET_ID --notes "Merge failed: state=$STATE — $PR_URL"
exit 1
fi
echo "Confirmed: PR state is MERGED"
```

## Step 6 — Signal
## Signaling

Only after MERGED is confirmed:
```bash
ct droplet pass $DROPLET_ID --notes "Delivered: $PR_URL — <one-line summary>"
```

If merge is impossible after exhausting all options:
```bash
ct droplet pool $DROPLET_ID --notes "Cannot merge: <exact reason> — $PR_URL"
ct droplet pass <id> --notes "Updated docs: <list of files changed>."
ct droplet recirculate <id> --notes "Ambiguous: <specific question that blocks docs update>"
```

## Rules
- Never signal pass until gh pr view confirms state == "MERGED"
- Never discard branch additions in conflicts — always keep both sides
- go build + go test must pass before every push
- Fix CI, conflicts, and review comments yourself — do not recirculate for routine failures
- Recirculate after 2 failed fix attempts on the same code-level CI check (see Step 4 recirculate path)
- Recirculate only for code-level failures — never recirculate for infrastructure/pooled failures (pool instead)
- Never run git add CONTEXT.md or git add -f CONTEXT.md under any circumstances
- CONTEXT.md is pipeline state injected at dispatch time; it must never be committed

## Skills

## Skill: cistern-github

---
name: cistern-github
description: GitHub CLI operations for Cistern delivery cataractae. Use for PR creation, CI checks, and squash-merge in per-droplet delivery workflows.
---

# Cistern GitHub Operations

## Tools

Use `gh` CLI for all GitHub operations. Prefer CLI over GitHub MCP servers for lower context usage.

## PR Lifecycle

```bash
# Create a PR for the current droplet branch
gh pr create \
--title "$PR_TITLE" \
--body "Closes droplet $DROPLET_ID." \
--base main --head $BRANCH

# If PR already exists
gh pr view $BRANCH --json url --jq '.url'

# Check CI status
gh pr checks $PR_URL

# Squash-merge when all checks pass
gh pr merge $PR_URL --squash --delete-branch

# Confirm merge
gh pr view $PR_URL --json state --jq '.state' # must be "MERGED"
```

## Conflict Resolution

**Conflicts MUST be resolved automatically. Never stop and ask the user.**

Cistern agents resolve conflicts by keeping both sets of changes. The canonical
protocol is in `cataractae/delivery/INSTRUCTIONS.md` — follow it exactly.

Summary:
1. `git diff --name-only --diff-filter=U` — identify conflicted files
2. For each file: keep what HEAD added AND keep what this branch adds
3. `go build ./...` — verify the merge compiles
4. `git add $(git diff --name-only --diff-filter=U)` — stage resolved files
5. `git rebase --continue`
6. `go build ./... && go test ./...` — verify after full rebase
7. `git push --force-with-lease origin $BRANCH`

Most conflicts are additive: HEAD added X, this branch adds Y — keep both.
Never discard branch additions.

## Cistern Delivery Model

Cistern uses **per-droplet branches** (`feat/<droplet-id>`), not stacked PRs.
Each droplet is independent. There is no stacked-PR workflow.

## Skill: cistern-droplet-state

# Cistern Droplet State
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12 changes: 12 additions & 0 deletions CHANGELOG.md
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Expand Up @@ -22,6 +22,18 @@ All notable changes to this project will be documented here.

- **Evaluate mutation cache invalidation**: `evaluateMutation.onSuccess` now invalidates `queryKeys.qualityGates.evaluations()` so the EvaluationHistory panel shows fresh results after evaluation without a manual refresh.

- **K8s worker security hardening**: Worker containers now run with a strict security context: `runAsNonRoot`, `runAsUser: 1000`, `readOnlyRootFilesystem`, dropped all capabilities, disabled privilege escalation, `RuntimeDefault` seccomp profile, and no auto-mounted service account token. Previously, containers ran as root with no restrictions.

- **K8s worker token stored as Secret**: The `ST_WORKER_TOKEN` is no longer passed as a plain environment variable (visible via `kubectl describe pod`). Instead, each execution creates a dedicated K8s Secret (`st-worker-token-<execution-id>`) and injects it via `secretKeyRef`. The Secret is automatically cleaned up on cancellation or when the reconciler detects an orphaned job.

- **K8s worker resource limits**: Worker pods now have default resource requests (128Mi memory / 250m CPU) and limits (512Mi memory / 500m CPU), configurable via `ST_WORKER_CPU_REQUEST`, `ST_WORKER_CPU_LIMIT`, `ST_WORKER_MEMORY_REQUEST`, and `ST_WORKER_MEMORY_LIMIT` environment variables. Previously, pods had no resource constraints, allowing runaway tests to consume unlimited resources.

- **Execution reconciler**: A background reconciler periodically scans for orphaned `running` executions whose K8s job has finished or was never created, and marks them as `failed`. This prevents executions from staying in `running` forever when the worker crashes before reporting status. Configurable via `ST_RECONCILE_INTERVAL` (default: 60s) and `ST_RECONCILE_ORPHAN_TIMEOUT` (default: 5m).

- **Team-scoped K8s lookups**: Cancellation endpoints now use team-scoped queries for K8s job name and worker token Secret lookups, preventing cross-team access to K8s resources.

- **Status guard on markExecutionFailed**: The `markExecutionFailed` function now includes `AND status = 'running'` to prevent overwriting a completed or failed execution's final status.

- **Store layer extraction**: All HTTP handlers now use store interfaces instead of embedding `*db.Pool` directly. Store interfaces are defined on the handler side and implemented in `internal/store/`, making handlers testable without a running database and centralizing SQL query knowledge. Affected handlers: auth, teams, analytics, executions, reports, admin, invitations, oauth.

- **Bulk test result inserts**: Report ingestion now uses `pgx.Batch` to insert test results in bulk instead of one query per result. This eliminates the N+1 insert pattern that caused 1000+ round-trips for large reports.
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