diff --git a/userspace/libsinsp/filter/ast.h b/userspace/libsinsp/filter/ast.h
index 4518d3056a..1f4a4dd9d2 100644
--- a/userspace/libsinsp/filter/ast.h
+++ b/userspace/libsinsp/filter/ast.h
@@ -18,6 +18,7 @@ limitations under the License.
 
 #pragma once
 
+#include <cstdint>
 #include <vector>
 #include <string>
 #include <algorithm>