diff --git a/premake/celt.lua b/premake/celt.lua
index 38f8304..731743b 100644
--- a/premake/celt.lua
+++ b/premake/celt.lua
@@ -17,8 +17,8 @@ group "external"
         }
         files
         {
-            base_dir .. "*.h",
-            base_dir .. "*.c"
+            base_dir .. "**.h",
+            base_dir .. "**.c"
         }
         excludes
         {
diff --git a/premake/json_checker.lua b/premake/json_checker.lua
index 57cab45..3cd3ac9 100644
--- a/premake/json_checker.lua
+++ b/premake/json_checker.lua
@@ -13,8 +13,8 @@ group "external"
         }
         files
         {
-            base_dir .. "*.h",
-            base_dir .. "*.cpp"
+            base_dir .. "**.h",
+            base_dir .. "**.cpp"
         }
     project "*"
 group ""
diff --git a/premake/snappy.lua b/premake/snappy.lua
index 2d6e9f5..ae729c7 100644
--- a/premake/snappy.lua
+++ b/premake/snappy.lua
@@ -13,8 +13,8 @@ group "external"
         }
         files
         {
-            base_dir .. "*.h",
-            base_dir .. "*.cc"
+            base_dir .. "**.h",
+            base_dir .. "**.cc"
         }
     project "*"
 group ""
diff --git a/premake/sourcesdk.lua b/premake/sourcesdk.lua
index fe14e03..caeb3d7 100644
--- a/premake/sourcesdk.lua
+++ b/premake/sourcesdk.lua
@@ -15,8 +15,8 @@ group "external"
         }
         files
         {
-            base_dir .. "*.h",
-            base_dir .. "*.cpp"
+            base_dir .. "**.h",
+            base_dir .. "**.cpp"
         }
         links
         {