diff --git a/.backlogit/queue/003-C.md b/.backlogit/archive/003-C.md
similarity index 66%
rename from .backlogit/queue/003-C.md
rename to .backlogit/archive/003-C.md
index ea95574..777727d 100644
--- a/.backlogit/queue/003-C.md
+++ b/.backlogit/archive/003-C.md
@@ -1,20 +1,20 @@
 ---
-id: "003-C"
-title: "Backlogit infrastructure hygiene"
 artifact_type: chore
-status: queued
-priority: medium
-description: "Fix backlog ID namespace collision at config level and gitignore backlogit DB files. Two config-only tasks that improve tooling reliability and repository cleanliness."
+commit: 53c65857a9c643af2daa46e81027b83d0e4c8ad3
+created_at: 2026-05-25T00:01:58.4202773-07:00
+id: 003-C
 labels:
-  - "backlogit"
-  - "config"
-  - "hygiene"
+    - backlogit
+    - config
+    - hygiene
+priority: medium
 references:
-  - "docs/plans/2026-05-24-backlogit-infra-hygiene-plan.md"
-  - "docs/decisions/2026-05-23-backlog-id-collision.md"
-  - "docs/decisions/2026-05-24-backlogit-infra-hygiene-deliberation.md"
-created_at: "2026-05-23T20:12:17.0000000-07:00"
-updated_at: "2026-05-23T21:17:23.0072735-07:00"
+    - docs/plans/2026-05-24-backlogit-infra-hygiene-plan.md
+    - docs/decisions/2026-05-23-backlog-id-collision.md
+    - docs/decisions/2026-05-24-backlogit-infra-hygiene-deliberation.md
+status: done
+title: Backlogit infrastructure hygiene
+updated_at: 2026-05-25T00:20:57.1769734-07:00
 ---
 
 ## Scope
diff --git a/.backlogit/queue/003.001-T.md b/.backlogit/archive/003.001-T.md
similarity index 62%
rename from .backlogit/queue/003.001-T.md
rename to .backlogit/archive/003.001-T.md
index a207cfe..4016047 100644
--- a/.backlogit/queue/003.001-T.md
+++ b/.backlogit/archive/003.001-T.md
@@ -1,19 +1,19 @@
 ---
-id: "003.001-T"
-title: "Gitignore backlogit DB files and untrack cached database"
 artifact_type: task
-status: queued
-priority: medium
-parent_id: "003-C"
-description: "Add .backlogit/*.db to .gitignore, run git rm --cached .backlogit/backlogit.db, verify stash.jsonl remains tracked."
+commit: 53c65857a9c643af2daa46e81027b83d0e4c8ad3
+created_at: 2026-05-24T23:56:05.0525385-07:00
+id: 003.001-T
 labels:
-  - "backlogit"
-  - "gitignore"
-  - "config"
+    - backlogit
+    - gitignore
+    - config
+parent_id: 003-C
+priority: medium
 references:
-  - "docs/plans/2026-05-24-backlogit-infra-hygiene-plan.md"
-created_at: "2026-05-23T20:12:17.0000000-07:00"
-updated_at: "2026-05-23T21:17:23.0072735-07:00"
+    - docs/plans/2026-05-24-backlogit-infra-hygiene-plan.md
+status: done
+title: Gitignore backlogit DB files and untrack cached database
+updated_at: 2026-05-25T00:20:49.3315002-07:00
 ---
 
 ## Implementation Notes
diff --git a/.backlogit/queue/003.002-T.md b/.backlogit/archive/003.002-T.md
similarity index 70%
rename from .backlogit/queue/003.002-T.md
rename to .backlogit/archive/003.002-T.md
index 2e9b398..ca3110f 100644
--- a/.backlogit/queue/003.002-T.md
+++ b/.backlogit/archive/003.002-T.md
@@ -1,20 +1,20 @@
 ---
-id: "003.002-T"
-title: "Fix chore task ID namespace with type-discriminated format"
 artifact_type: task
-status: queued
-priority: medium
-parent_id: "003-C"
-description: "Modify .backlogit/config.yaml chore name_format to use type-discriminated prefix so chore task IDs do not collide with feature task IDs, after confirming config.yaml is the authoritative artifact-type config."
+commit: 53c65857a9c643af2daa46e81027b83d0e4c8ad3
+created_at: 2026-05-24T23:56:05.1354611-07:00
+id: 003.002-T
 labels:
-  - "backlogit"
-  - "config"
-  - "id-collision"
+    - backlogit
+    - config
+    - id-collision
+parent_id: 003-C
+priority: medium
 references:
-  - "docs/plans/2026-05-24-backlogit-infra-hygiene-plan.md"
-  - "docs/decisions/2026-05-23-backlog-id-collision.md"
-created_at: "2026-05-23T20:12:17.0000000-07:00"
-updated_at: "2026-05-23T21:17:23.0072735-07:00"
+    - docs/plans/2026-05-24-backlogit-infra-hygiene-plan.md
+    - docs/decisions/2026-05-23-backlog-id-collision.md
+status: done
+title: Fix chore task ID namespace with type-discriminated format
+updated_at: 2026-05-25T00:20:49.7703861-07:00
 ---
 
 ## Implementation Notes
diff --git a/.backlogit/backlogit.db b/.backlogit/backlogit.db
deleted file mode 100644
index a0ae190..0000000
Binary files a/.backlogit/backlogit.db and /dev/null differ
diff --git a/.backlogit/config.yaml b/.backlogit/config.yaml
index c49f5cc..7cd3c3f 100644
--- a/.backlogit/config.yaml
+++ b/.backlogit/config.yaml
@@ -24,7 +24,7 @@ artifact_types:
     chore:
         prefix: C
         suffix: -C
-        name_format: '{NNN}{suffix}'
+        name_format: '{NNN}C{suffix}'
         allowed_children:
             - task
             - review
diff --git a/.backlogit/hooks_queue.jsonl b/.backlogit/hooks_queue.jsonl
index 943d5f8..4aed4a4 100644
--- a/.backlogit/hooks_queue.jsonl
+++ b/.backlogit/hooks_queue.jsonl
@@ -38,3 +38,12 @@
 {"seq":38,"timestamp":"2026-05-23T07:31:07.0478639Z","event_type":"create_artifact","payload":{"actor":"backlogit","artifact_type":"task","changed_fields":["id","title","status"],"item_id":"002.002-T","schema_version":1,"status_delta":{"from":"","to":"queued"},"title_delta":{"from":"","to":"Audit and fix hooks_queue.jsonl sequence renumbering"}}}
 {"seq":39,"timestamp":"2026-05-23T07:31:14.9383464Z","event_type":"create_artifact","payload":{"actor":"backlogit","artifact_type":"task","changed_fields":["id","title","status"],"item_id":"002.003-T","schema_version":1,"status_delta":{"from":"","to":"queued"},"title_delta":{"from":"","to":"Investigate and resolve backlog ID namespace collision"}}}
 {"seq":40,"timestamp":"2026-05-23T07:31:29.2709242Z","event_type":"create_artifact","payload":{"actor":"backlogit","artifact_type":"shipment","changed_fields":["id","title","status"],"item_id":"004-S","schema_version":1,"status_delta":{"from":"","to":"queued"},"title_delta":{"from":"","to":"Repository governance and tooling integrity"}}}
+{"seq":41,"timestamp":"2026-05-25T07:02:09.0260392Z","event_type":"update_artifact","payload":{"actor":"backlogit","artifact_type":"chore","changed_fields":["status"],"item_id":"003-C","schema_version":1,"status_delta":{"from":"queued","to":"active"}}}
+{"seq":42,"timestamp":"2026-05-25T07:02:23.6517097Z","event_type":"move_shipment_status","payload":{"actor":"backlogit","artifact_type":"shipment","changed_fields":["status"],"item_id":"005-S","schema_version":1,"status_delta":{"from":"queued","to":"active"}}}
+{"seq":43,"timestamp":"2026-05-25T07:03:47.6850551Z","event_type":"update_artifact","payload":{"actor":"backlogit","artifact_type":"task","changed_fields":["status"],"item_id":"003.001-T","schema_version":1}}
+{"seq":44,"timestamp":"2026-05-25T07:07:19.3625937Z","event_type":"update_artifact","payload":{"actor":"backlogit","artifact_type":"task","changed_fields":["status"],"item_id":"003.002-T","schema_version":1}}
+{"seq":45,"timestamp":"2026-05-25T07:08:09.7848437Z","event_type":"update_artifact","payload":{"actor":"backlogit","artifact_type":"chore","changed_fields":["status"],"item_id":"003-C","schema_version":1,"status_delta":{"from":"active","to":"done"}}}
+{"seq":46,"timestamp":"2026-05-25T07:08:16.0470778Z","event_type":"update_artifact","payload":{"actor":"backlogit","artifact_type":"task","changed_fields":["status"],"item_id":"003.002-T","schema_version":1,"status_delta":{"from":"active","to":"done"}}}
+{"seq":47,"timestamp":"2026-05-25T07:08:18.9856322Z","event_type":"update_artifact","payload":{"actor":"backlogit","artifact_type":"task","changed_fields":["status"],"item_id":"003.001-T","schema_version":1,"status_delta":{"from":"active","to":"done"}}}
+{"seq":48,"timestamp":"2026-05-25T07:20:56.5389828Z","event_type":"update_artifact","payload":{"actor":"backlogit","artifact_type":"task","changed_fields":["commit"],"item_id":"003.001-T","schema_version":1}}
+{"seq":49,"timestamp":"2026-05-25T07:20:58.0366915Z","event_type":"update_artifact","payload":{"actor":"backlogit","artifact_type":"chore","changed_fields":["commit"],"item_id":"003-C","schema_version":1}}
diff --git a/.backlogit/queue/005-S.md b/.backlogit/queue/005-S.md
index cc4a988..f686bf4 100644
--- a/.backlogit/queue/005-S.md
+++ b/.backlogit/queue/005-S.md
@@ -1,23 +1,22 @@
 ---
-id: "005-S"
-title: "Backlogit infrastructure hygiene"
 artifact_type: shipment
-status: queued
-priority: medium
-description: "Ship backlogit config hygiene: gitignore DB files + fix chore task ID namespace collision."
+created_at: 2026-05-24T23:56:05.1874839-07:00
+custom_fields:
+    items:
+        - 003-C
+        - 003.001-T
+        - 003.002-T
+id: 005-S
 labels:
-  - "backlogit"
-  - "config"
-  - "hygiene"
+    - backlogit
+    - config
+    - hygiene
+priority: medium
 references:
-  - "docs/plans/2026-05-24-backlogit-infra-hygiene-plan.md"
-created_at: "2026-05-23T20:12:17.0000000-07:00"
-custom_fields:
-  items:
-    - 003-C
-    - 003.001-T
-    - 003.002-T
-updated_at: "2026-05-23T21:17:23.0072735-07:00"
+    - docs/plans/2026-05-24-backlogit-infra-hygiene-plan.md
+status: active
+title: Backlogit infrastructure hygiene
+updated_at: 2026-05-25T00:02:20.5263868-07:00
 ---
 
 ## Manifest
diff --git a/.gitignore b/.gitignore
index 1d135eb..cea9c36 100644
--- a/.gitignore
+++ b/.gitignore
@@ -23,6 +23,10 @@
 .*.lock
 **/.*.lock
 
+# backlogit (tool-managed cache)
+.backlogit/*.db
+.backlogit/*.db-*
+
 # Untracked files
 **/*.txt
 **/*.log
diff --git a/docs/compound/backlogit-id-collision-archival-protocol.md b/docs/compound/backlogit-id-collision-archival-protocol.md
index 4be354b..2c945ee 100644
--- a/docs/compound/backlogit-id-collision-archival-protocol.md
+++ b/docs/compound/backlogit-id-collision-archival-protocol.md
@@ -3,10 +3,18 @@ title: Backlogit ID collision — delete-not-move archival for colliding chore t
 tags: [backlogit, archival, id-collision, chore, ship-agent]
 shipped_in: 004-S
 date: 2026-05-23
+status: superseded
+superseded_by: 005-S
+superseded_on: 2026-05-25
 ---
 
 # Backlogit ID Collision: Delete-Not-Move Archival Protocol
 
+> [!IMPORTANT]
+> Superseded by shipment `005-S`, which changes chore ID formatting in
+> `.backlogit/config.yaml` to use a type-discriminated namespace. Keep this
+> document as historical context for pre-fix archive collisions only.
+
 ## Context
 
 Backlogit assigns tasks a hierarchical ID derived from the parent's counter