Review and harden ZMQ DB backups: centralize backup decision, kill mutation survivor

By architect.

docs/reviews/zmq-db-backups-summary.md

@@ -0,0 +1,48 @@
+# zmq-db-backups — Architect Review Summary
+
+**By architect.**
+
+## Task and commits reviewed
+- Task: `zmq-db-backups` (refactorer handoff, `merge_and_process refactorer 89731964de`)
+- Merged `swarmforge-refactorer` (fast-forward) — commits:
+  - `edcb8c8` Spec ZMQ-mode DB backups every epoch
+  - `2d193c6` Implement ZMQ-mode DB backups every epoch blocks (coder)
+  - `8973196` Refactor ZMQ DB backups: add property coverage and constructor test (refactorer)
+
+## Architectural findings and fixes
+- **Cohesion / DRY (fixed):** In `psf-memo-block-indexer.js` the IBD catch-up path
+  duplicated the backup decision (`if (nextBlockHeight % epoch === 0)`) that the
+  `BackupDb.maybeBackupDb` use case already encapsulates, while the ZMQ live path
+  correctly delegated the decision. Removed the redundant guard and now use the
+  use case's boolean return to decide whether to log. The decision now lives in
+  exactly one place.
+- **Boundaries (confirmed good):** `BackupDb` (use case) is a pure decision
+  function depending only on the `dbCtrl.backupDb` adapter interface; the HTTP
+  IO lives in `src/adapters/backup-db.js`. The use case is fully testable without
+  IO. No framework/persistence structures leak across the boundary.
+- **Hardening (added):** Added a unit test for the `height === 1` boundary to kill
+  a surviving mutation (`height > 0` → `height > 1`).
+
+## Verification results
+- **Language mutation** (`mutate4javascript`, `--max-workers 8`): `src/use-cases/backup-db.js`
+  — **6 killed, 0 survived, 0 uncovered** (after adding the `height === 1` test).
+- **CRAP** (`crap4javascript`): `BackupDb.maybeBackupDb` CC=3, 100% cov, CRAP=3.0
+  (threshold 8.0). Pass.
+- **DRY** (`dry4javascript`): no new duplication from this task. Pre-existing
+  duplicates in `rpc.js` and `set-name/set-profile/set-profile-pic` are out of
+  scope for this handoff.
+- **Soft Gherkin acceptance mutation** (`gherkin-mutator --level soft`): 11 killed,
+  **4 survived — all documented equivalents**. The survivors (m8, m9, m14, m15)
+  mutate height/epoch values in the two "0 backup" example rows to other
+  non-multiple values; the observable result (0 backups) is unchanged, so the
+  scenarios cannot distinguish them. No action needed.
+
+## Suite status
+- `psf-memo-indexer` unit: **54 passing** (was 53; +1 new boundary test)
+- `psf-memo-indexer` property: **4 passing**
+- `psf-memo-indexer` acceptance: **3 generated files, all passing**
+- `psf-memo-indexer` lint (`standard`): clean
+
+## Handoffs sent
+- `git_handoff` to coder and refactorer (`priority: 00`) with the review commit
+  for follow-up review.

psf-memo-indexer/psf-memo-block-indexer.js

@@ -48,9 +48,12 @@ async function start () {
           process.exit(1)
         }
 
-        if (nextBlockHeight % config.dbBackupEpoch === 0) {
+        const backedUp = await useCases.backupDb.maybeBackupDb(
+          nextBlockHeight,
+          config.dbBackupEpoch
+        )
+        if (backedUp) {
           console.log(`Creating DB backup at block ${nextBlockHeight}`)
-          await useCases.backupDb.maybeBackupDb(nextBlockHeight, config.dbBackupEpoch)
         }
 
         biggestBlockHeight = await queue.addToQueue(adapters.rpc.getBlockCount, {})

psf-memo-indexer/specs/zmq-mode-db-backups.feature

@@ -1,3 +1,7 @@
+# acceptance-mutation-manifest-begin
+# {"version":1,"tested_at":"2026-08-28T17:15:12.126220806Z","feature_name":"ZMQ mode DB backups","feature_path":"/home/trout/work/psf-memo/.worktrees/architect/psf-memo-indexer/specs/zmq-mode-db-backups.feature","background_hash":"dbd9928c8a005b3b4846976d2144892926158c50a05868292fc9cdc0a03ef735","implementation_hash":"unknown","scenarios":[]}
+# acceptance-mutation-manifest-end
+
 # Scenarios: ZMQ mode DB backups - 1
 Feature: ZMQ mode DB backups
 

psf-memo-indexer/src/use-cases/backup-db.js

@@ -25,3 +25,7 @@ class BackupDb {
 }
 
 export default BackupDb
+
+// mutate4javascript-manifest-begin
+// {"version":1,"tested_at":"2026-08-28T17:14:22.022Z","module_hash":"5bb4a36a5e28a1be19c5e544518576bafd81b30df24db30b8ca64690f300c27c","functions":[{"id":"func/BackupDb.constructor","name":"BackupDb.constructor","line":6,"end_line":12,"hash":"50c4a5ffabb1fe5848ab489c49aeebca4e8a808fd773ab9e603fc55d85fff08d"},{"id":"func/BackupDb.maybeBackupDb","name":"BackupDb.maybeBackupDb","line":14,"end_line":24,"hash":"0fc3ba6a7f6cfc52b05103e7ff164318d0a11f56372d307a2e6f3c5220df0a59"}]}
+// mutate4javascript-manifest-end

psf-memo-indexer/test/unit/use-cases/backup-db.unit.js

@@ -56,6 +56,14 @@ describe('#BackupDb', () => {
       assert.equal(adapters.dbCtrl.backupDb.callCount, 0)
     })
 
+    it('should request a backup at height 1 with epoch 1', async () => {
+      const result = await uut.maybeBackupDb(1, 1)
+
+      assert.equal(result, true)
+      assert.equal(adapters.dbCtrl.backupDb.callCount, 1)
+      assert.deepEqual(adapters.dbCtrl.backupDb.firstCall.args, [1, 1])
+    })
+
     it('should support a configurable epoch smaller than 1000', async () => {
       const result = await uut.maybeBackupDb(500, 500)