diff --git a/library/declare_lib.nim b/library/declare_lib.nim
new file mode 100644
index 000000000..188de8549
--- /dev/null
+++ b/library/declare_lib.nim
@@ -0,0 +1,10 @@
+import ffi
+import waku/factory/waku
+
+declareLibrary("waku")
+
+proc set_event_callback(
+    ctx: ptr FFIContext[Waku], callback: FFICallBack, userData: pointer
+) {.dynlib, exportc, cdecl.} =
+  ctx[].eventCallback = cast[pointer](callback)
+  ctx[].eventUserData = userData