diff --git a/AMBuilder b/AMBuilder
index eba2e40..badf479 100644
--- a/AMBuilder
+++ b/AMBuilder
@@ -5,7 +5,7 @@ projectName = 'socket'
 
 # smsdk_ext.cpp will be automatically added later
 sourceFiles = [
-  'extension.cpp',
+  'Extension.cpp',
 ]
 
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