diff --git a/lib/micropython/gen-frozen.sh b/lib/micropython/gen-frozen.sh
index a032c5d85563b883b7767ea460d8439ea343c9f2..d9638bfeec4063502b55e042d02c6f2f4c9c0d15 100755
--- a/lib/micropython/gen-frozen.sh
+++ b/lib/micropython/gen-frozen.sh
@@ -14,5 +14,5 @@ QSTR_HEADER="$(dirname "$QSTR_HEADER")/qstrdefs.preprocessed.h"
 "$PYTHON" "$SOURCE_DIR"/micropython/tools/mpy-tool.py \
     --freeze \
     --qstr-header "$QSTR_HEADER" \
-    -mlongint-impl longlong \
+    -mlongint-impl mpz \
     "$@" >"$OUTPUT"
diff --git a/pycardium/mpconfigport.h b/pycardium/mpconfigport.h
index 744a38e38cd2c25ea037e90ac420d4f2403c0d2b..8ee59352b18439b511b6ae3e99d66742b58b945d 100644
--- a/pycardium/mpconfigport.h
+++ b/pycardium/mpconfigport.h
@@ -18,7 +18,7 @@
 #define MICROPY_ENABLE_GC                   (1)
 #define MICROPY_FLOAT_IMPL                  (MICROPY_FLOAT_IMPL_FLOAT)
 #define MICROPY_HELPER_REPL                 (1)
-#define MICROPY_LONGINT_IMPL                (MICROPY_LONGINT_IMPL_LONGLONG)
+#define MICROPY_LONGINT_IMPL                (MICROPY_LONGINT_IMPL_MPZ)
 
 #define MICROPY_ENABLE_SCHEDULER            (1)