diff --git a/backend/routers/training_planning.py b/backend/routers/training_planning.py
index 461999e..dfa8fa8 100644
--- a/backend/routers/training_planning.py
+++ b/backend/routers/training_planning.py
@@ -1863,6 +1863,7 @@ def create_training_unit(data: dict, tenant: TenantContext = Depends(get_tenant_
             lead_ins,
         )
         if assistant_set:
+            av_db = None if assistant_val is None else PsycopgJson(assistant_val)
             cur.execute(
                 """
                 INSERT INTO training_units (
@@ -1874,7 +1875,7 @@ def create_training_unit(data: dict, tenant: TenantContext = Depends(get_tenant_
                 ) VALUES (%s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s)
                 RETURNING id
                 """,
-                base_params + (assistant_val,),
+                base_params + (av_db,),
             )
         else:
             cur.execute(
@@ -2013,7 +2014,7 @@ def update_training_unit(unit_id: int, data: dict, tenant: TenantContext = Depen
                     eff_lead_for_co,
                 )
                 assist_sql = ", assistant_trainer_profile_ids = %s"
-                assist_params.append(na)
+                assist_params.append(None if na is None else PsycopgJson(na))
 
             debrief_frag = ""
             if "debrief_completed" in data and not is_blueprint:
diff --git a/backend/version.py b/backend/version.py
index 9e7a6d1..013f24b 100644
--- a/backend/version.py
+++ b/backend/version.py
@@ -1,6 +1,6 @@
 # Shinkan Jinkendo Version Information
 
-APP_VERSION = "0.8.129"
+APP_VERSION = "0.8.130"
 BUILD_DATE = "2026-05-12"
 DB_SCHEMA_VERSION = "20260514062"
 
@@ -24,7 +24,7 @@ MODULE_VERSIONS = {
     "exercises": "2.28.0",  # GET /api/exercises Keyset cursor_updated_at + cursor_id; Sortierung id als Tie-break
     "training_units": "0.3.0",  # GET /api/training-units Keyset cursor_planned_date + cursor_id (+ optional cursor_planned_time); Sort mit id-Tiebreak
     "training_programs": "0.1.0",
-    "planning": "0.9.4",  # list_training_units: Keyset-Pagination + stabile Sortierung (NULLS LAST + id)
+    "planning": "0.9.5",  # assistant_trainer_profile_ids: JSONB-Write mit PsycopgJson (Fix 500 bei Co-Liste)
     "dashboard": "1.1.0",  # GET /api/dashboard/kpis inkl. training_home (ein Client-Roundtrip für KPIs + nächste Termine)
     "training_modules": "1.0.0",
     "import_wiki": "1.0.0",
@@ -36,6 +36,13 @@ MODULE_VERSIONS = {
 }
 
 CHANGELOG = [
+    {
+        "version": "0.8.130",
+        "date": "2026-05-13",
+        "changes": [
+            "Fix: PUT/POST training_units — assistant_trainer_profile_ids als JSONB mit psycopg2.extras.Json schreiben (rohe Python-Liste → ProgrammingError/500 bei Co-Zuweisung).",
+        ],
+    },
     {
         "version": "0.8.129",
         "date": "2026-05-13",