diff --git a/app/assets/semantics/__init__.py b/app/assets/semantics/__init__.py
index 222ac4796..334943ae2 100644
--- a/app/assets/semantics/__init__.py
+++ b/app/assets/semantics/__init__.py
@@ -101,9 +101,18 @@ def run_pending_semantics_steps(interrupt_check: InterruptCheck | None = None) -
             )
             return applied
 
-        with create_session() as session:
-            set_semantics_version(session, step.version)
-            session.commit()
+        try:
+            with create_session() as session:
+                set_semantics_version(session, step.version)
+                session.commit()
+        except Exception:
+            logging.exception(
+                "Asset semantics step %d (%s) finished but could not be stamped, "
+                "so it runs again; its own writes are already committed",
+                step.version,
+                step.description,
+            )
+            return applied
 
         applied += 1
         logging.info(
diff --git a/app/assets/semantics/reproject_derived.py b/app/assets/semantics/reproject_derived.py
index 0f24c6f57..ee899819d 100644
--- a/app/assets/semantics/reproject_derived.py
+++ b/app/assets/semantics/reproject_derived.py
@@ -129,14 +129,6 @@ def _reproject_batch(
             summary.absent_files += 1
             continue
 
-        if unchanged:
-            summary.unchanged_files += 1
-        else:
-            # Hand it to the verify path rather than re-read the file for hash and size.
-            summary.changed_files += 1
-            if not row.needs_verify:
-                set_needs_verify.append(row.reference_id)
-
         try:
             derived_tags = set(
                 normalize_tags(get_path_derived_tags_from_path(row.file_path))
@@ -145,6 +137,14 @@ def _reproject_batch(
             summary.unclassified_paths += 1
             continue
 
+        if unchanged:
+            summary.unchanged_files += 1
+        else:
+            # Hand it to the verify path rather than re-read the file for hash and size.
+            summary.changed_files += 1
+            if not row.needs_verify:
+                set_needs_verify.append(row.reference_id)
+
         loader_path = compute_loader_path(row.file_path)
         if loader_path != row.loader_path:
             loader_paths[row.reference_id] = loader_path
diff --git a/tests-unit/assets_test/test_semantics_reset.py b/tests-unit/assets_test/test_semantics_reset.py
index 1d88c1192..f75329719 100644
--- a/tests-unit/assets_test/test_semantics_reset.py
+++ b/tests-unit/assets_test/test_semantics_reset.py
@@ -427,6 +427,24 @@ class TestFileState:
             "a file that is simply gone is the scanner's business, not unfinished work"
         )
 
+    def test_unclassified_row_is_not_flagged_for_verify(self, session, comfy_dirs):
+        """needs_verify is a write like any other; it must skip out-of-view rows too."""
+        _register(
+            session,
+            _write(comfy_dirs["elsewhere"], "model.safetensors"),
+            "ref-1",
+            mtime_ns=1,
+        )
+
+        summary = reproject_derived_state()
+
+        session.expire_all()
+        assert session.get(AssetReference, "ref-1").needs_verify is False, (
+            "the one write that did not skip made 'leaves it alone' untrue"
+        )
+        assert summary.unclassified_paths == 1
+        assert summary.changed_files == 0
+
     def test_path_outside_every_known_root_is_left_alone(self, session, comfy_dirs):
         path = _write(comfy_dirs["elsewhere"], "model.safetensors")
         _register(
@@ -623,6 +641,27 @@ class TestRunner:
         ):
             assert run_pending_semantics_steps() == 0
 
+    def test_stamp_failure_does_not_escape_to_the_caller(self, session, comfy_dirs):
+        """The seeder calls this; a transient lock here must not abort its scan."""
+        _register(
+            session,
+            _write(comfy_dirs["checkpoints"], "model.safetensors"),
+            "ref-1",
+            loader_path=None,
+        )
+
+        with patch(
+            "app.assets.semantics.set_semantics_version",
+            side_effect=RuntimeError("database is locked"),
+        ):
+            assert run_pending_semantics_steps() == 0
+
+        session.expire_all()
+        assert get_semantics_version(session) == 0
+        assert (
+            session.get(AssetReference, "ref-1").loader_path == "model.safetensors"
+        ), "the step's own committed work survives a failed stamp"
+
     def test_stamp_is_not_advanced_when_a_step_raises(self, session, comfy_dirs):
         def _explode(_interrupt_check):
             raise RuntimeError("step failed")