diff --git a/src/gpu/modal_distill.py b/src/gpu/modal_distill.py
index e81c1f8..148194a 100644
--- a/src/gpu/modal_distill.py
+++ b/src/gpu/modal_distill.py
@@ -1149,9 +1149,18 @@ def _usable(ck: Path) -> bool:
         key=lambda p: int(p.name.split("-")[1]),
     )
     if ckpts:
-        student.load_state_dict(
-            torch.load(ckpts[-1] / "student.pt", map_location="cpu", weights_only=True)
-        )
+        sd = torch.load(ckpts[-1] / "student.pt", map_location="cpu", weights_only=True)
+        missing, unexpected = student.load_state_dict(sd, strict=False)
+        # engram params may be absent in older checkpoints: the module
+        # is zero-init (identity), so a fresh table is a safe resume.
+        # Anything else missing or unexpected is a real mismatch.
+        bad_missing = [k for k in missing if not k.startswith("_engram.")]
+        if bad_missing or unexpected:
+            raise RuntimeError(
+                f"resume mismatch: missing={bad_missing} unexpected={list(unexpected)}"
+            )
+        if missing:
+            print(f"[{spec_id}] resume with fresh engram: {missing}", flush=True)
         optimizer.load_state_dict(
             torch.load(ckpts[-1] / "optim.pt", map_location="cpu", weights_only=True)
         )