diff --git a/haiku_rag_slim/haiku/rag/ingester/sources/fs.py b/haiku_rag_slim/haiku/rag/ingester/sources/fs.py
index 8b944e04..8de87469 100644
--- a/haiku_rag_slim/haiku/rag/ingester/sources/fs.py
+++ b/haiku_rag_slim/haiku/rag/ingester/sources/fs.py
@@ -139,7 +139,12 @@ class FSSource:
             if not self.filter.include_file(str(path)):
                 continue
             uri = path.as_uri()
-            revision = str(path.stat().st_mtime_ns)
+            try:
+                revision = str(path.stat().st_mtime_ns)
+            except FileNotFoundError:
+                # File was deleted between the os.walk() and stat() call.
+                # Skip it — the next sweep (or watchfiles) will emit DELETE.
+                continue
             seen.add(uri)
             previous = snapshot.get(uri)
             kind = (
diff --git a/tests/ingester/test_fs_source.py b/tests/ingester/test_fs_source.py
index df32304f..f5e088cf 100644
--- a/tests/ingester/test_fs_source.py
+++ b/tests/ingester/test_fs_source.py
@@ -131,6 +131,37 @@ async def test_fs_source_discover_respects_extension_filter(fs_root: Path):
     assert (fs_root / "b.txt").as_uri() not in uris
 
 
+@pytest.mark.asyncio
+async def test_fs_source_discover_skips_file_deleted_during_stat(
+    fs_root: Path, monkeypatch
+):
+    """A file deleted between is_file() and stat() should be silently
+    skipped instead of crashing the entire discover() sweep."""
+    victim = fs_root / "b.txt"
+    original_stat = Path.stat
+    victim_calls = 0
+
+    def _stat_that_fails_on_second_call(self, *args, **kwargs):
+        nonlocal victim_calls
+        if self == victim:
+            victim_calls += 1
+            # First calls are from is_symlink/is_file; the later call
+            # is the explicit stat().st_mtime_ns we want to fail.
+            if victim_calls > 2:
+                raise FileNotFoundError(f"[Errno 2] No such file: '{self}'")
+        return original_stat(self, *args, **kwargs)
+
+    monkeypatch.setattr(Path, "stat", _stat_that_fails_on_second_call)
+
+    src = FSSource(root=fs_root, supported_extensions=[".md", ".txt"])
+    events = [e async for e in src.discover(since=None)]
+    uris = {e.uri for e in events}
+    # b.txt was skipped due to the simulated race; a.md and sub/c.md are fine.
+    assert (fs_root / "a.md").as_uri() in uris
+    assert (fs_root / "sub" / "c.md").as_uri() in uris
+    assert victim.as_uri() not in uris
+
+
 @pytest.mark.asyncio
 async def test_fs_source_discover_respects_ignore_patterns(fs_root: Path):
     src = FSSource(