diff --git a/include/groundext.h b/include/groundext.h
new file mode 100644
index 0000000..e8c35ac
--- /dev/null
+++ b/include/groundext.h
@@ -0,0 +1,37 @@
+#ifndef GROUND_EXT_H
+#define GROUND_EXT_H
+
+#include "groundvm.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// Forward declaration of the scope structure used in interpreter
+struct GroundScope;
+typedef struct GroundScope GroundScope;
+
+/*
+ * Function pointer type for native functions.
+ * scope: The current execution scope (opaque).
+ * args: A List of arguments passed to the function.
+ */
+typedef GroundValue (*NativeGroundFunction)(GroundScope* scope, List args);
+
+/*
+ * Registers a native function in the given scope.
+ * 
+ * scope: The scope to register the function in.
+ * name: The name of the function in Ground.
+ * fn: The C function to call.
+ * returnType: The return type of the function.
+ * argCount: The number of arguments the function expects.
+ * ...: A sequence of (GroundValueType type, char* name) for each argument.
+ */
+void groundAddNativeFunction(GroundScope* scope, char* name, NativeGroundFunction fn, GroundValueType returnType, int argCount, ...);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif