diff --git a/xmake.lua b/xmake.lua
index 1241360..1785976 100644
--- a/xmake.lua
+++ b/xmake.lua
@@ -71,11 +71,8 @@ target("SimpleProtocol")
     add_files("src/sp/**.cpp")
     set_group("Library")
     set_kind("$(kind)")
-    
-    local includeFolders = {"common", "default", "io", "protocol"}
-    for _, folder in ipairs(includeFolders) do
-        add_headerfiles("include/(sp/" .. folder .. "/**.h)")
-    end
+
+    add_headerfiles("include/(sp/**.h)", "include/(sp/**.inl)")
 
     -- adding extensions
     for name, module in table.orderpairs(modules) do
@@ -86,6 +83,7 @@ target("SimpleProtocol")
 
     -- we don't want extensions
     remove_files("src/sp/extensions/**.cpp")
+    remove_headerfiles("include/(sp/extension/**.h)")
 
     -- we need this for endian functions
     if is_os("windows") then