diff --git a/src/SPC/builder/Extension.php b/src/SPC/builder/Extension.php
index 331d2986..60cc3708 100644
--- a/src/SPC/builder/Extension.php
+++ b/src/SPC/builder/Extension.php
@@ -11,8 +11,6 @@ use SPC\exception\ValidationException;
 use SPC\exception\WrongUsageException;
 use SPC\store\Config;
 use SPC\store\FileSystem;
-use SPC\toolchain\ToolchainManager;
-use SPC\toolchain\ZigToolchain;
 use SPC\util\SPCConfigUtil;
 use SPC\util\SPCTarget;