Patch 2026.1.11 (#967)

Author: danh91

AGENTS.md

@@ -771,6 +771,41 @@ Shipment.objects.select_related('shipper', 'recipient', 'carrier_connection')
 Shipment.objects.prefetch_related('parcels', 'customs', 'rates')
 ```
 
+### ⚠️ N+1 Query Prevention (Critical!)
+
+N+1 queries are a common Django ORM pitfall that can severely degrade performance,
+especially on serverless databases (Aurora Serverless) where each query incurs connection overhead.
+
+**Always review loops that touch the database:**
+
+```python
+# ❌ BAD - N+1: one UPDATE per tracker in a loop
+for tracker in trackers:
+    tracker.status = compute_status(tracker)
+    tracker.save()  # N individual UPDATE queries
+
+# ❌ BAD - N+1: one SELECT per related object in a loop
+for shipment in shipments:
+    print(shipment.carrier.name)  # N individual SELECT queries (lazy loading)
+
+# ✅ GOOD - Bulk update: single UPDATE for all trackers
+for tracker in trackers:
+    tracker.status = compute_status(tracker)
+Tracking.objects.bulk_update(trackers, ["status", "updated_at"])
+
+# ✅ GOOD - Prefetch/select related: single JOIN query
+shipments = Shipment.objects.select_related("carrier").filter(...)
+for shipment in shipments:
+    print(shipment.carrier.name)  # No extra queries
+```
+
+**Key patterns to watch for:**
+- `model.save()` inside a loop → use `bulk_update()` or `bulk_create()`
+- `model.related_field.attribute` without `select_related` → add `select_related()`
+- `model.related_set.all()` without `prefetch_related` → add `prefetch_related()`
+- `update_or_create()` in high-concurrency paths → use split `create()`/`filter().update()` to avoid `SELECT FOR UPDATE` lock contention
+- Individual `filter().update()` calls in a loop → collect changes and use `bulk_update()`
+
 ---
 
 ## Background Jobs (Huey)

CHANGELOG.md

@@ -1,3 +1,54 @@
+# Karrio 2026.1.11
+
+## Changes
+
+### Feat
+
+- feat: add markup feature gating with `meta.feature_gate` for conditional markup application
+- feat: add feature_gate field to markup editors (inline and advanced admin)
+- feat: add tracker bulk webhook resend and per-row action menu
+- feat: add batch webhook resend API endpoint
+- feat: integrate worker action buttons in devtools frontend
+- feat: add worker management GraphQL mutations for admin
+- feat: add markup filtering by meta category, plan, active status and type
+- feat: improve CSV preview with progressive markup totals and column filtering
+- feat: add markups management to rate sheet editor and improve markup dialogs
+
+### Fix
+
+- fix: make Health view scrollable and wrap maintenance actions in card
+- fix: skip empty rate rows in CSV preview
+- fix: align tracker checkbox column width with shipments table
+- fix: show exact page counts instead of "of many" in devtools pagination
+- fix: resolve duplicate TaskExecution records causing stuck executing status
+- fix: use icontains for meta and metadata value filters on markups
+- fix: port rate sheet editor layout improvements and bug fixes 
+
+### Perf
+
+- perf: cache middleware auth result to prevent duplicate token DB lookups
+- perf: reuse pre-loaded carriers in buy_shipment_label to avoid duplicate connection queries
+- perf: batch constance config queries to eliminate N+1 in shipment creation
+- perf: batch tracker saves to eliminate N+1 UPDATE queries in tracking pipeline
+- perf: eliminate SELECT FOR UPDATE lock contention in task signal handler
+
+### Refactor
+
+- refactor: update devtools drawer, navbar, and rate sheet CSV preview
+- refactor: use generic meta_key/meta_value and metadata_key/metadata_value filters for markups
+
+### Test
+
+- test: add batch webhook resend tests
+- test: add admin CRUD tests for markup meta field and filters
+- test: add feature-gated markup applicability tests
+
+### Chore
+
+- chore: generate admin migrations
+
+---
+
 # Karrio 2026.1.10
 
 ## Changes