diff --git a/client/blueprints/measure.py b/client/blueprints/measure.py
index 8206d2d..b0eae1d 100644
--- a/client/blueprints/measure.py
+++ b/client/blueprints/measure.py
@@ -121,11 +121,21 @@ def task_execute(task_id: int):
     lot_number = session.get("lot_number", "")
     serial_number = session.get("serial_number", "")
 
+    # Load all task IDs for this recipe (ordered) for auto-advance
+    recipe_id = task_resp.get("recipe_id")
+    all_task_ids = []
+    if recipe_id:
+        tasks_resp = api_client.get(f"/api/recipes/{recipe_id}/tasks")
+        if isinstance(tasks_resp, list):
+            sorted_tasks = sorted(tasks_resp, key=lambda t: t.get("order_index", 0))
+            all_task_ids = [t["id"] for t in sorted_tasks]
+
     return render_template(
         "measure/task_execute.html",
         task=task_resp,
         lot_number=lot_number,
         serial_number=serial_number,
+        all_task_ids=all_task_ids,
     )
 
 
@@ -150,18 +160,44 @@ def task_complete(recipe_id: int):
         )
         return redirect(url_for("measure.select_recipe"))
 
+    # Load tasks+subtasks for this recipe to build subtask and task lookup
+    tasks_resp = api_client.get(f"/api/recipes/{recipe_id}/tasks")
+    subtask_map = {}
+    subtask_task_map = {}  # subtask_id → task info
+    if isinstance(tasks_resp, list):
+        for task in tasks_resp:
+            for st in task.get("subtasks", []):
+                subtask_map[st["id"]] = st
+                subtask_task_map[st["id"]] = {
+                    "id": task["id"],
+                    "title": task.get("title", ""),
+                    "order_index": task.get("order_index", 0),
+                }
+
     # Load measurements if version_id provided
     measurements = []
     if version_id:
         meas_resp = api_client.get(
             "/api/measurements",
-            params={"version_id": version_id},
+            params={"version_id": version_id, "per_page": 500},
         )
         if not (isinstance(meas_resp, dict) and meas_resp.get("error")):
-            measurements = (
+            raw = (
                 meas_resp if isinstance(meas_resp, list)
                 else meas_resp.get("items", [])
             )
+            # Enrich each measurement with nested subtask data
+            for m in raw:
+                st = subtask_map.get(m.get("subtask_id"), {})
+                m["subtask"] = st
+                m["task_info"] = subtask_task_map.get(m.get("subtask_id"), {})
+                # Compute deviation if not present
+                if m.get("deviation") is None and st.get("nominal") is not None:
+                    try:
+                        m["deviation"] = m["value"] - st["nominal"]
+                    except (TypeError, KeyError):
+                        m["deviation"] = 0.0
+            measurements = raw
 
     lot_number = session.get("lot_number", "")
     serial_number = session.get("serial_number", "")
@@ -243,25 +279,22 @@ def save_measurement():
 
     # Validate required fields
     subtask_id = data.get("subtask_id")
-    task_id = data.get("task_id")
+    version_id = data.get("version_id")
     value = data.get("value")
 
-    if subtask_id is None or task_id is None or value is None:
+    if subtask_id is None or version_id is None or value is None:
         return jsonify({
             "error": True,
-            "detail": _("Dati mancanti: subtask_id, task_id e value sono obbligatori"),
+            "detail": _("Dati mancanti: subtask_id, version_id e value sono obbligatori"),
         }), 400
 
     # Build payload for the FastAPI backend
     payload = {
         "subtask_id": subtask_id,
-        "task_id": task_id,
+        "version_id": version_id,
         "value": value,
-        "pass_fail": data.get("pass_fail", ""),
-        "deviation": data.get("deviation"),
         "lot_number": data.get("lot_number", session.get("lot_number", "")),
         "serial_number": data.get("serial_number", session.get("serial_number", "")),
-        "measured_by": session.get("user_id"),
         "input_method": data.get("input_method", "manual"),
     }
 
diff --git a/client/static/css/themes.css b/client/static/css/themes.css
index 2221253..2021fdf 100644
--- a/client/static/css/themes.css
+++ b/client/static/css/themes.css
@@ -38,6 +38,15 @@
 
 /* ---- Dark Theme ---- */
 .dark {
+  --color-primary: #60A5FA;
+  --color-primary-dark: #3B82F6;
+  --color-primary-light: #93C5FD;
+  --color-accent: #93C5FD;
+
+  --color-pass: #34D399;
+  --color-warning: #FBBF24;
+  --color-fail: #F87171;
+
   --bg-primary: #0F172A;
   --bg-secondary: #1E293B;
   --bg-card: #334155;
@@ -48,7 +57,7 @@
   --text-muted: #64748B;
 
   --border-color: #475569;
-  --border-focus: #3B82F6;
+  --border-focus: #60A5FA;
 
   --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.3);
   --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4), 0 2px 4px -2px rgba(0, 0, 0, 0.3);
@@ -252,11 +261,22 @@ textarea:focus-visible {
   border-color: var(--color-primary);
 }
 
+.dark .btn-primary {
+  background: #3B82F6;
+  color: #FFFFFF;
+  border-color: #3B82F6;
+}
+
 .btn-primary:hover:not(:disabled) {
   background: var(--color-primary-dark);
   border-color: var(--color-primary-dark);
 }
 
+.dark .btn-primary:hover:not(:disabled) {
+  background: #2563EB;
+  border-color: #2563EB;
+}
+
 .btn-secondary {
   background: transparent;
   color: var(--text-secondary);
diff --git a/client/templates/components/navbar.html b/client/templates/components/navbar.html
index 548b329..d81aaa6 100644
--- a/client/templates/components/navbar.html
+++ b/client/templates/components/navbar.html
@@ -1,6 +1,6 @@
 <!-- TieMeasureFlow Navbar -->
 <nav class="sticky top-0 z-40 bg-[var(--bg-card)] border-b border-[var(--border-color)] shadow-sm transition-colors duration-300"
-     x-data="{ mobileOpen: false, userDropdown: false, adminDropdown: false }">
+     x-data="{ mobileOpen: false, userDropdown: false }">
   <div class="max-w-7xl mx-auto px-4 sm:px-6 lg:px-8">
     <div class="flex items-center justify-between h-14">
 
@@ -15,9 +15,6 @@
                  alt="TieMeasureFlow"
                  class="h-8 w-auto">
           {% endif %}
-          <span class="text-lg font-bold text-[var(--text-primary)] tracking-tight hidden sm:inline">
-            TieMeasureFlow
-          </span>
         </a>
       </div>
 
@@ -76,53 +73,6 @@
         </a>
         {% endif %}
 
-        {# Admin: dropdown #}
-        {% if current_user.get('is_admin') %}
-        <div class="relative" x-data="{ open: false }" @click.outside="open = false">
-          <button @click="open = !open"
-                  class="nav-link group flex items-center gap-2 px-3 py-2 rounded-lg text-sm font-medium
-                         text-[var(--text-secondary)] hover:text-primary hover:bg-primary-50 dark:hover:bg-primary-900/20
-                         transition-colors duration-200"
-                  :class="{ 'text-primary bg-primary-50 dark:bg-primary-900/20': open }">
-            <!-- Cog Icon -->
-            <svg class="w-4.5 h-4.5" fill="none" stroke="currentColor" stroke-width="1.75" viewBox="0 0 24 24">
-              <path stroke-linecap="round" stroke-linejoin="round" d="M10.325 4.317c.426-1.756 2.924-1.756 3.35 0a1.724 1.724 0 002.573 1.066c1.543-.94 3.31.826 2.37 2.37a1.724 1.724 0 001.066 2.573c1.756.426 1.756 2.924 0 3.35a1.724 1.724 0 00-1.066 2.573c.94 1.543-.826 3.31-2.37 2.37a1.724 1.724 0 00-2.573 1.066c-.426 1.756-2.924 1.756-3.35 0a1.724 1.724 0 00-2.573-1.066c-1.543.94-3.31-.826-2.37-2.37a1.724 1.724 0 00-1.066-2.573c-1.756-.426-1.756-2.924 0-3.35a1.724 1.724 0 001.066-2.573c-.94-1.543.826-3.31 2.37-2.37.996.608 2.296.07 2.572-1.065z"/>
-              <path stroke-linecap="round" stroke-linejoin="round" d="M15 12a3 3 0 11-6 0 3 3 0 016 0z"/>
-            </svg>
-            <span>{{ _('Admin') }}</span>
-            <svg class="w-3.5 h-3.5 transition-transform duration-200" :class="{ 'rotate-180': open }"
-                 fill="none" stroke="currentColor" stroke-width="2" viewBox="0 0 24 24">
-              <path stroke-linecap="round" stroke-linejoin="round" d="M19 9l-7 7-7-7"/>
-            </svg>
-          </button>
-
-          <!-- Admin Dropdown -->
-          <div x-show="open"
-               x-transition:enter="transition ease-out duration-150"
-               x-transition:enter-start="opacity-0 scale-95 -translate-y-1"
-               x-transition:enter-end="opacity-100 scale-100 translate-y-0"
-               x-transition:leave="transition ease-in duration-100"
-               x-transition:leave-start="opacity-100 scale-100"
-               x-transition:leave-end="opacity-0 scale-95"
-               class="absolute left-0 mt-1 w-48 rounded-lg bg-[var(--bg-card)] border border-[var(--border-color)]
-                      shadow-lg py-1 z-50">
-            <a href="#" class="flex items-center gap-2.5 px-4 py-2.5 text-sm text-[var(--text-secondary)]
-                               hover:text-primary hover:bg-primary-50 dark:hover:bg-primary-900/20 transition-colors">
-              <svg class="w-4 h-4" fill="none" stroke="currentColor" stroke-width="1.75" viewBox="0 0 24 24">
-                <path stroke-linecap="round" stroke-linejoin="round" d="M12 4.354a4 4 0 110 5.292M15 21H3v-1a6 6 0 0112 0v1zm0 0h6v-1a6 6 0 00-9-5.197M13 7a4 4 0 11-8 0 4 4 0 018 0z"/>
-              </svg>
-              {{ _('Utenti') }}
-            </a>
-            <a href="#" class="flex items-center gap-2.5 px-4 py-2.5 text-sm text-[var(--text-secondary)]
-                               hover:text-primary hover:bg-primary-50 dark:hover:bg-primary-900/20 transition-colors">
-              <svg class="w-4 h-4" fill="none" stroke="currentColor" stroke-width="1.75" viewBox="0 0 24 24">
-                <path stroke-linecap="round" stroke-linejoin="round" d="M12 6V4m0 2a2 2 0 100 4m0-4a2 2 0 110 4m-6 8a2 2 0 100-4m0 4a2 2 0 110-4m0 4v2m0-6V4m6 6v10m6-2a2 2 0 100-4m0 4a2 2 0 110-4m0 4v2m0-6V4"/>
-              </svg>
-              {{ _('Impostazioni') }}
-            </a>
-          </div>
-        </div>
-        {% endif %}
 
       </div>
       {% endif %}
@@ -298,28 +248,6 @@
       </a>
       {% endif %}
 
-      {% if current_user.get('is_admin') %}
-      <div class="border-t border-[var(--border-color)] my-2"></div>
-      <p class="px-3 py-1 text-xs font-semibold text-[var(--text-secondary)] uppercase tracking-wider">{{ _('Admin') }}</p>
-      <a href="#"
-         class="flex items-center gap-3 px-3 py-2.5 rounded-lg text-sm font-medium
-                text-[var(--text-secondary)] hover:text-primary hover:bg-primary-50 dark:hover:bg-primary-900/20
-                transition-colors">
-        <svg class="w-5 h-5" fill="none" stroke="currentColor" stroke-width="1.75" viewBox="0 0 24 24">
-          <path stroke-linecap="round" stroke-linejoin="round" d="M12 4.354a4 4 0 110 5.292M15 21H3v-1a6 6 0 0112 0v1zm0 0h6v-1a6 6 0 00-9-5.197M13 7a4 4 0 11-8 0 4 4 0 018 0z"/>
-        </svg>
-        {{ _('Utenti') }}
-      </a>
-      <a href="#"
-         class="flex items-center gap-3 px-3 py-2.5 rounded-lg text-sm font-medium
-                text-[var(--text-secondary)] hover:text-primary hover:bg-primary-50 dark:hover:bg-primary-900/20
-                transition-colors">
-        <svg class="w-5 h-5" fill="none" stroke="currentColor" stroke-width="1.75" viewBox="0 0 24 24">
-          <path stroke-linecap="round" stroke-linejoin="round" d="M12 6V4m0 2a2 2 0 100 4m0-4a2 2 0 110 4m-6 8a2 2 0 100-4m0 4a2 2 0 110-4m0 4v2m0-6V4m6 6v10m6-2a2 2 0 100-4m0 4a2 2 0 110-4m0 4v2m0-6V4"/>
-        </svg>
-        {{ _('Impostazioni') }}
-      </a>
-      {% endif %}
 
     </div>
   </div>
diff --git a/client/templates/measure/task_complete.html b/client/templates/measure/task_complete.html
index 54464b2..f3e255f 100644
--- a/client/templates/measure/task_complete.html
+++ b/client/templates/measure/task_complete.html
@@ -164,7 +164,8 @@
             <table class="tmf-table">
                 <thead>
                     <tr>
-                        <th class="text-center">#</th>
+                        <th class="text-center">{{ _('Data/Ora') }}</th>
+                        <th>{{ _('Task') }}</th>
                         <th>{{ _('Descrizione') }}</th>
                         <th class="text-right">{{ _('Nominale') }}</th>
                         <th class="text-right">{{ _('Valore') }}</th>
@@ -174,10 +175,13 @@
                     </tr>
                 </thead>
                 <tbody>
-                    {% for m in measurements|sort(attribute='subtask.marker_number') %}
+                    {% for m in measurements|sort(attribute='task_info.order_index,subtask.marker_number') %}
                     <tr>
-                        <td class="text-center font-mono font-medium" style="color: var(--text-primary);">
-                            {{ m.subtask.marker_number }}
+                        <td class="text-center font-mono text-xs" style="color: var(--text-secondary);">
+                            {{ m.measured_at[:16]|replace('T', ' ') if m.measured_at else '-' }}
+                        </td>
+                        <td style="color: var(--text-secondary);" class="text-sm">
+                            {{ m.task_info.title if m.task_info else '-' }}
                         </td>
                         <td style="color: var(--text-primary);">
                             {{ m.subtask.description }}
@@ -203,14 +207,14 @@
                             {% endif %}
                         </td>
                         <td class="text-center">
-                            {% if m.method == 'manual' %}
+                            {% if m.input_method == 'manual' %}
                             <div class="inline-flex items-center gap-1" style="color: var(--text-secondary);">
                                 <svg class="h-5 w-5" fill="none" viewBox="0 0 24 24" stroke="currentColor">
                                     <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M15.232 5.232l3.536 3.536m-2.036-5.036a2.5 2.5 0 113.536 3.536L6.5 21.036H3v-3.572L16.732 3.732z"/>
                                 </svg>
                                 <span class="text-sm">{{ _('Manuale') }}</span>
                             </div>
-                            {% elif m.method == 'caliper' %}
+                            {% elif m.input_method == 'usb_caliper' %}
                             <div class="inline-flex items-center gap-1" style="color: var(--text-secondary);">
                                 <svg class="h-5 w-5" fill="none" viewBox="0 0 24 24" stroke="currentColor">
                                     <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M9 3v2m6-2v2M9 19v2m6-2v2M5 9H3m2 6H3m18-6h-2m2 6h-2M7 19h10a2 2 0 002-2V7a2 2 0 00-2-2H7a2 2 0 00-2 2v10a2 2 0 002 2zM9 9h6v6H9V9z"/>
diff --git a/client/templates/measure/task_execute.html b/client/templates/measure/task_execute.html
index 13f1fb0..956d4cb 100644
--- a/client/templates/measure/task_execute.html
+++ b/client/templates/measure/task_execute.html
@@ -54,6 +54,7 @@
 {% block content %}
 <script>
   window.__taskAnnotations = {{ task.annotations_json|default('null')|tojson }};
+  window.__allTaskIds = {{ all_task_ids|tojson }};
 </script>
 <div class="min-h-[calc(100vh-3.5rem)] flex flex-col"
      x-data="taskExecute()"
@@ -210,23 +211,43 @@
                     class="shrink-0 flex items-center gap-1.5 px-3 py-1.5 rounded-lg border text-xs font-medium transition-all duration-200"
                     :class="idx === currentIndex
                       ? 'bg-primary text-white border-primary shadow-md marker-active-pulse'
-                      : isMeasured(st.id)
+                      : getMeasurementStatus(st.id) === 'pass'
                         ? 'bg-measure-pass/10 text-measure-pass border-measure-pass/30 hover:bg-measure-pass/20'
-                        : 'bg-[var(--bg-card)] text-[var(--text-secondary)] border-[var(--border-color)] hover:border-primary/50 hover:text-primary'
+                        : getMeasurementStatus(st.id) === 'fail'
+                          ? 'bg-red-50 dark:bg-red-900/20 text-measure-fail border-measure-fail/30 hover:bg-red-100 dark:hover:bg-red-900/30'
+                          : getMeasurementStatus(st.id) === 'warning'
+                            ? 'bg-amber-50 dark:bg-amber-900/20 text-measure-warning border-measure-warning/30 hover:bg-amber-100 dark:hover:bg-amber-900/30'
+                            : 'bg-[var(--bg-card)] text-[var(--text-secondary)] border-[var(--border-color)] hover:border-primary/50 hover:text-primary'
                     ">
               <span class="inline-flex items-center justify-center w-5 h-5 rounded-full text-[10px] font-bold"
                     :class="idx === currentIndex
                       ? 'bg-white/20'
-                      : isMeasured(st.id)
+                      : getMeasurementStatus(st.id) === 'pass'
                         ? 'bg-measure-pass/20'
-                        : 'bg-[var(--bg-secondary)]'
+                        : getMeasurementStatus(st.id) === 'fail'
+                          ? 'bg-measure-fail/20'
+                          : getMeasurementStatus(st.id) === 'warning'
+                            ? 'bg-measure-warning/20'
+                            : 'bg-[var(--bg-secondary)]'
                     "
                     x-text="st.marker_number"></span>
               <span x-text="st.description" class="truncate max-w-[100px]"></span>
-              {# Check icon if measured #}
-              <svg x-show="isMeasured(st.id)" class="w-3.5 h-3.5 text-measure-pass shrink-0" fill="none" stroke="currentColor" stroke-width="2.5" viewBox="0 0 24 24">
-                <path stroke-linecap="round" stroke-linejoin="round" d="M5 13l4 4L19 7"/>
-              </svg>
+              {# Status icon: pass=check, fail=X, warning=! #}
+              <template x-if="getMeasurementStatus(st.id) === 'pass'">
+                <svg class="w-3.5 h-3.5 text-measure-pass shrink-0" fill="none" stroke="currentColor" stroke-width="2.5" viewBox="0 0 24 24">
+                  <path stroke-linecap="round" stroke-linejoin="round" d="M5 13l4 4L19 7"/>
+                </svg>
+              </template>
+              <template x-if="getMeasurementStatus(st.id) === 'fail'">
+                <svg class="w-3.5 h-3.5 text-measure-fail shrink-0" fill="none" stroke="currentColor" stroke-width="2.5" viewBox="0 0 24 24">
+                  <path stroke-linecap="round" stroke-linejoin="round" d="M6 18L18 6M6 6l12 12"/>
+                </svg>
+              </template>
+              <template x-if="getMeasurementStatus(st.id) === 'warning'">
+                <svg class="w-3.5 h-3.5 text-measure-warning shrink-0" fill="none" stroke="currentColor" stroke-width="2.5" viewBox="0 0 24 24">
+                  <path stroke-linecap="round" stroke-linejoin="round" d="M12 9v3.75m-9.303 3.376c-.866 1.5.217 3.374 1.948 3.374h14.71c1.73 0 2.813-1.874 1.948-3.374L13.949 3.378c-.866-1.5-3.032-1.5-3.898 0L2.697 16.126zM12 15.75h.007v.008H12v-.008z"/>
+                </svg>
+              </template>
             </button>
           </template>
         </div>
@@ -628,6 +649,11 @@ function taskExecute() {
       return m ? m.value : null;
     },
 
+    getMeasurementStatus(subtaskId) {
+      const m = this.measurements.find(m => m.subtask_id === subtaskId);
+      return m ? m.pass_fail : null;
+    },
+
     // ---- Handle numpad confirm ----
     async handleMeasurement(value, inputMethod) {
       if (!this.currentSubtask || this.saving) return;
@@ -652,10 +678,8 @@ function taskExecute() {
           },
           body: JSON.stringify({
             subtask_id: this.currentSubtask.id,
-            task_id: this.task.id,
+            version_id: this.task.version_id,
             value: value,
-            pass_fail: pf,
-            deviation: dev,
             lot_number: this.lotNumber,
             serial_number: this.serialNumber,
             input_method: inputMethod || 'manual',
@@ -670,20 +694,32 @@ function taskExecute() {
           return;
         }
 
-        // Record measurement locally
-        this.measurements.push({
-          subtask_id: this.currentSubtask.id,
-          value: value,
-          pass_fail: pf,
-          deviation: dev,
-        });
+        // Record measurement locally (replace if already measured)
+        const existingIdx = this.measurements.findIndex(m => m.subtask_id === this.currentSubtask.id);
+        const mEntry = { subtask_id: this.currentSubtask.id, value, pass_fail: pf, deviation: dev };
+        if (existingIdx !== -1) {
+          this.measurements.splice(existingIdx, 1, mEntry);
+        } else {
+          this.measurements.push(mEntry);
+        }
 
         this.saving = false;
 
+        // Pause 1s to let user see the result (pass/fail/warning)
+        await new Promise(r => setTimeout(r, 1000));
+
         // Check if all done
         if (this.completedCount >= this.totalSubtasks) {
-          // Show completion overlay
-          this.showCompletionOverlay = true;
+          // Auto-advance to next task, or show overlay on last task
+          const taskIds = window.__allTaskIds || [];
+          const currentIdx = taskIds.indexOf(this.task.id);
+          if (currentIdx >= 0 && currentIdx < taskIds.length - 1) {
+            // Navigate to next task
+            window.location.href = '{{ url_for("measure.task_execute", task_id=0) }}'.replace('/0', '/' + taskIds[currentIdx + 1]);
+          } else {
+            // Last task (or unknown): show completion overlay
+            this.showCompletionOverlay = true;
+          }
           return;
         }
 
diff --git a/server/config.py b/server/config.py
index fa54978..697e5c3 100644
--- a/server/config.py
+++ b/server/config.py
@@ -52,7 +52,7 @@ class Settings(BaseSettings):
         """Absolute path to upload directory."""
         return Path(__file__).parent / self.upload_dir
 
-    model_config = {"env_file": "../.env", "env_file_encoding": "utf-8"}
+    model_config = {"env_file": "../.env", "env_file_encoding": "utf-8", "extra": "ignore"}
 
 
 settings = Settings()
diff --git a/server/routers/recipes.py b/server/routers/recipes.py
index 060e254..d3211f8 100644
--- a/server/routers/recipes.py
+++ b/server/routers/recipes.py
@@ -93,10 +93,19 @@ async def update_recipe(
     user: User = Depends(require_maker),
     db: AsyncSession = Depends(get_db),
 ):
-    """Update a recipe - creates a new version via copy-on-write. Requires Maker role."""
-    new_version = await recipe_service.create_new_version(db, recipe_id, data, user)
+    """Update a recipe. Creates a new version only if the current one has measurements.
+    Otherwise updates in-place. Requires Maker role.
+    """
+    current = await recipe_service.get_current_version(db, recipe_id)
+    has_measurements = await recipe_service.version_has_measurements(db, current.id)
+
+    if has_measurements:
+        # Copy-on-write: create new version to preserve measurement data
+        await recipe_service.create_new_version(db, recipe_id, data, user)
+    else:
+        # No measurements yet: update in-place
+        await recipe_service.update_current_version(db, recipe_id, data)
 
-    # Reload full recipe for consistent response
     recipe = await recipe_service.get_recipe_detail(db, recipe_id)
     return _recipe_to_response(recipe)
 
diff --git a/server/routers/tasks.py b/server/routers/tasks.py
index 3036038..e608192 100644
--- a/server/routers/tasks.py
+++ b/server/routers/tasks.py
@@ -153,11 +153,19 @@ async def create_task(
             detail="Cannot modify an inactive recipe",
         )
 
-    # Copy-on-write: create new version with existing tasks cloned
-    from schemas.recipe import RecipeUpdate
-    new_version = await recipe_service.create_new_version(
-        db, recipe_id, RecipeUpdate(change_notes=f"Added task: {data.title}"), user
-    )
+    # Check if current version has measurements
+    current = await recipe_service.get_current_version(db, recipe_id)
+    has_measurements = await recipe_service.version_has_measurements(db, current.id)
+
+    if has_measurements:
+        # Copy-on-write: create new version preserving measurement data
+        from schemas.recipe import RecipeUpdate
+        new_version = await recipe_service.create_new_version(
+            db, recipe_id, RecipeUpdate(change_notes=f"Added task: {data.title}"), user
+        )
+    else:
+        # No measurements: use current version directly
+        new_version = current
 
     # Determine order_index (append at end)
     max_order = max((t.order_index for t in new_version.tasks), default=-1)
diff --git a/server/services/recipe_service.py b/server/services/recipe_service.py
index 7985469..b155831 100644
--- a/server/services/recipe_service.py
+++ b/server/services/recipe_service.py
@@ -357,6 +357,82 @@ async def get_measurement_count(
     return count_result.scalar_one()
 
 
+async def version_has_measurements(db: AsyncSession, version_id: int) -> bool:
+    """Check if any measurements exist for the given version."""
+    result = await db.execute(
+        select(func.count()).select_from(Measurement).where(
+            Measurement.version_id == version_id
+        )
+    )
+    return result.scalar_one() > 0
+
+
+async def update_current_version(
+    db: AsyncSession,
+    recipe_id: int,
+    data: RecipeUpdate,
+) -> RecipeVersion:
+    """Update recipe header in-place on the current version (no copy-on-write)."""
+    # Apply header updates (name, description)
+    update_fields: dict = {}
+    if data.name is not None:
+        update_fields["name"] = data.name
+    if data.description is not None:
+        update_fields["description"] = data.description
+    if update_fields:
+        await db.execute(
+            update(Recipe).where(Recipe.id == recipe_id).values(**update_fields)
+        )
+
+    # Apply task-level file updates to first task (same logic as create_new_version)
+    current = await _get_current_version(db, recipe_id)
+    if data.file_path is not None or data.annotations_json is not None:
+        result_tasks = await db.execute(
+            select(RecipeTask)
+            .where(RecipeTask.version_id == current.id)
+            .order_by(RecipeTask.order_index)
+        )
+        tasks = list(result_tasks.scalars().all())
+        if tasks:
+            first_task = tasks[0]
+            if data.file_path is not None:
+                first_task.file_path = data.file_path
+                if data.file_type:
+                    first_task.file_type = data.file_type
+                elif data.file_path.lower().endswith(".pdf"):
+                    first_task.file_type = "pdf"
+                else:
+                    first_task.file_type = "image"
+            if data.annotations_json is not None:
+                first_task.annotations_json = data.annotations_json
+        else:
+            # No tasks yet — create a default task to hold the drawing
+            default_task = RecipeTask(
+                version_id=current.id,
+                order_index=0,
+                title="Technical Drawing",
+                file_path=data.file_path,
+                file_type=data.file_type or (
+                    "pdf" if data.file_path and data.file_path.lower().endswith(".pdf")
+                    else "image"
+                ),
+                annotations_json=data.annotations_json,
+            )
+            db.add(default_task)
+
+    await db.flush()
+
+    # Reload version with tasks for response
+    result = await db.execute(
+        select(RecipeVersion)
+        .where(RecipeVersion.id == current.id)
+        .options(
+            selectinload(RecipeVersion.tasks).selectinload(RecipeTask.subtasks)
+        )
+    )
+    return result.scalar_one()
+
+
 async def list_recipes(
     db: AsyncSession,
     page: int = 1,