diff --git a/src/runtime/alloc.h b/src/runtime/alloc.h
index 5aaa19cd71f3..69b76ae6b871 100644
--- a/src/runtime/alloc.h
+++ b/src/runtime/alloc.h
@@ -7,13 +7,14 @@ Author: Leonardo de Moura
 #pragma once
 #include <stddef.h>
 #include <stdint.h>
+#include <lean/lean.h>
 
 namespace lean {
 void init_thread_heap();
-void * alloc(size_t sz);
-void dealloc(void * o, size_t sz);
-void add_heartbeats(uint64_t count);
-uint64_t get_num_heartbeats();
+LEAN_EXPORT void * alloc(size_t sz);
+LEAN_EXPORT void dealloc(void * o, size_t sz);
+LEAN_EXPORT void add_heartbeats(uint64_t count);
+LEAN_EXPORT uint64_t get_num_heartbeats();
 void initialize_alloc();
 void finalize_alloc();
 }