diff --git a/ocr-service/main.py b/ocr-service/main.py
index 16b2d955..754ed75b 100644
--- a/ocr-service/main.py
+++ b/ocr-service/main.py
@@ -305,20 +305,25 @@ def _parse_best_checkpoint(checkpoint_dir: str) -> tuple[float | None, int]:
 
 
 def _find_best_model(checkpoint_dir: str) -> str | None:
-    """Return the checkpoint file with the highest validation metric, or any model file."""
-    pattern = re.compile(r"checkpoint_(\d+)-([0-9.]+)\.(ckpt|mlmodel)$")
+    """Return the best final model file produced by ketos train.
+
+    With --weights-format coreml, ketos writes ``best_<score>.mlmodel``.
+    Falls back to any .mlmodel in the directory.
+    """
+    # Prefer the named best file (e.g. best_0.8256.mlmodel or best_0.8256.safetensors)
+    best_pattern = re.compile(r"best_([0-9.]+)\.(mlmodel|safetensors)$")
     best_acc: float | None = None
     best_path: str | None = None
     for fname in os.listdir(checkpoint_dir):
-        m = pattern.match(fname)
+        m = best_pattern.match(fname)
         if m:
-            acc = float(m.group(2))
+            acc = float(m.group(1))
             if best_acc is None or acc > best_acc:
                 best_acc = acc
                 best_path = os.path.join(checkpoint_dir, fname)
     if best_path:
         return best_path
-    # Fallback: any .mlmodel file in the directory
+    # Fallback: any .mlmodel file
     for fname in os.listdir(checkpoint_dir):
         if fname.endswith(".mlmodel"):
             return os.path.join(checkpoint_dir, fname)
@@ -369,6 +374,7 @@ async def train_model(
                 "ketos", "--workers", "0", "--device", "cpu", "--threads", "2",
                 "train",
                 "-f", "page",
+                "--weights-format", "coreml",
                 "-o", checkpoint_dir,
                 "-q", "fixed",
                 "-N", "10",