diff --git a/conda_lock/conda_lock.py b/conda_lock/conda_lock.py
index 0bc43fdc9..e188dfb1f 100644
--- a/conda_lock/conda_lock.py
+++ b/conda_lock/conda_lock.py
@@ -373,7 +373,7 @@ def make_lock_specs(
         else:
             channels = lock_spec.channels
         lock_spec.channels = channels
-        res[sys.platform] = lock_spec
+        res[plat] = lock_spec
     return res