diff --git a/lib/core/build.py b/lib/core/build.py
index da862ee0..b549b3a9 100644
--- a/lib/core/build.py
+++ b/lib/core/build.py
@@ -21,5 +21,6 @@
     deps=[
         "dep/agg",
         "dep/stb",
+        "+fmt_lib",
     ],
 )
diff --git a/lib/vfs/build.py b/lib/vfs/build.py
index 878276a8..585770e6 100644
--- a/lib/vfs/build.py
+++ b/lib/vfs/build.py
@@ -28,4 +28,8 @@
         "lib/vfs/sectorinterface.h": "./sectorinterface.h",
         "lib/vfs/vfs.h": "./vfs.h",
     },
-    deps=["+lib"])
+    deps=[
+        "+lib",
+        "+fmt_lib",
+    ],
+)