diff --git a/c_src/appsignal_extension.c b/c_src/appsignal_extension.c
index 25c2772fe..d4d595dc9 100644
--- a/c_src/appsignal_extension.c
+++ b/c_src/appsignal_extension.c
@@ -8,7 +8,7 @@
 #include <stdio.h>
 #include <string.h>
 #include <unistd.h>
-#include <appsignal_extension.h>
+#include <appsignal.h>
 
 static ErlNifResourceType *appsignal_transaction_type = NULL;
 static ErlNifResourceType *appsignal_data_type = NULL;
diff --git a/mix_helpers.exs b/mix_helpers.exs
index 055a21c45..ef16060e5 100644
--- a/mix_helpers.exs
+++ b/mix_helpers.exs
@@ -16,7 +16,7 @@ defmodule Mix.Appsignal.Helper do
 
     System.put_env("LIB_DIR", priv_dir())
 
-    unless has_file("appsignal-agent") and has_file("appsignal_extension.h") and has_file("appsignal_extension.so") do
+    unless has_file("appsignal-agent") and has_file("appsignal.h") and has_file("appsignal_extension.so") do
 
       File.mkdir_p!(priv_dir())
       try do