diff --git a/.a0/current_status.md b/.a0/current_status.md
index 913bd1d..3f825c3 100644
--- a/.a0/current_status.md
+++ b/.a0/current_status.md
@@ -1,28 +1,29 @@
 # LeoCRM — Current Status
 **Phase**: 3 (Implementation)
 **Plan Mode**: implementation_allowed
-**Last completed**: T04 — DMS Plugin Backend (commit fdb41da, pushed to Forgejo)
-**Date**: 2026-06-29
+**Last completed**: T05 — Calendar Plugin Backend (commit 7fbeeda, pushed to Forgejo)
+**Date**: 2026-06-30
 
 ## Completed Tasks
 - T01: Core Infrastructure + Multi-Tenant + Auth System ✅
 - T02: Company + Contact + Import/Export System ✅
 - T03: Plugin System Framework ✅
 - T04: DMS Plugin Backend (Folders, Files, Preview, OnlyOffice, Shares, Search, Bulk) ✅
+- T05: Calendar Plugin Backend (Appointments, Tasks, Kanban, ICS, Resources, Recurrence) ✅
 - T07a: Frontend Core SPA — Shell, Auth, Routing, i18n, UI Library ✅
 - T07b: Frontend Feature Pages — Companies, Contacts, Settings, Audit, Dashboard, Search ✅
 - T09: KI-Copilot API + Hybrid Workflow Engine Backend ✅
 - T11: Tags Plugin + Permissions Plugin + Entity Links Backend ✅
 
-## T04 Verification
-- 106 DMS tests pass (27 AC + 38 error-path + 41 coverage)
-- Coverage: 97.90% (routes.py 97.56%)
-- 412 total tests pass (full regression, 0 failures)
+## T05 Verification
+- 69 calendar tests pass (33 AC integration + 36 recurrence unit)
+- Coverage: 86.87% (routes.py 82.33%, recurrence.py 90.43%, ics_utils.py 75.21%)
+- 481 total tests pass (full regression, 0 failures)
 - 0 ruff errors, ruff format clean
-- Pushed to Forgejo: fdb41da
+- Pushed to Forgejo: 7fbeeda
 
 ## Next Candidates
-- T05: Calendar Plugin Backend (Appointments, Tasks, Kanban, Resources, ICS)
 - T06: Mail Plugin Backend (IMAP/SMTP, Threading, Templates, Rules, PGP)
-- T10: Monitoring, Performance, Documentation
 - T08a: DMS Frontend (prerequisite T04 ✅ — now unblocked)
+- T08b: Calendar Frontend (prerequisite T05 ✅ — now unblocked)
+- T10: Monitoring, Performance, Documentation
diff --git a/.a0/next_steps.md b/.a0/next_steps.md
index b0947e0..b6bb276 100644
--- a/.a0/next_steps.md
+++ b/.a0/next_steps.md
@@ -1,8 +1,8 @@
 # LeoCRM — Next Steps
 1. **User decision needed**: Which task next?
-   - T05: Calendar Plugin Backend (Appointments, Tasks, Kanban, Resources, ICS)
    - T06: Mail Plugin Backend (IMAP/SMTP, Threading, Templates, Rules, PGP)
    - T08a: DMS Frontend (prerequisite T04 ✅ — now unblocked)
+   - T08b: Calendar Frontend (prerequisite T05 ✅ — now unblocked)
    - T10: Monitoring, Performance, Documentation & Environment Config
 2. After task selection: delegate to implementation_engineer with briefing
 3. After implementation: test_debug_engineer for validation
diff --git a/.a0/worklog.md b/.a0/worklog.md
index a5c6d3d..54ac221 100644
--- a/.a0/worklog.md
+++ b/.a0/worklog.md
@@ -125,3 +125,12 @@
 - **Verification**: 68 tests pass, coverage 66.61% (dead code gaps explained)
 - **Deliverables**: 3 plugin dirs (tags, permissions, entity_links), 3 test files, migration_runner fix, builtins registration, conftest updates
 - **Subagents used**: 3 (implementation_engineer x3 — initial, fixes, coverage improvement)
+
+## 2026-06-30 01:15 — T05 Complete
+- **Task**: T05 — Calendar Plugin Backend (Appointments, Tasks, Kanban, ICS, Resources, Recurrence)
+- **Commit**: 7fbeeda (14 files, +3674 lines)
+- **Pushed**: Forgejo remote, HEAD=7fbeeda
+- **Verification**: 69 calendar tests pass (33 AC + 36 recurrence unit), 86.87% coverage, 481 total tests pass (full regression), 0 ruff errors
+- **Deliverables**: Calendar plugin dir (8 files: __init__.py, plugin.py, routes.py, models.py, schemas.py, recurrence.py, ics_utils.py, migrations/0001_initial.sql), 2 test files (test_calendar.py 1075 lines, test_recurrence_unit.py), conftest.py calendar fixtures, builtins/__init__.py registration
+- **Subagents used**: 2 (implementation_engineer x2 — initial implementation + 8 bug fixes)
+- **Key fixes**: MissingGreenlet (db.refresh after flush), CSV export route ordering, ICS token commit, recurrence midnight boundary, datetime.UTC deprecation