diff --git a/interface.lisp b/interface.lisp
index 98078a6afdaff1394157388a1a161d07033c7d46..8767a55c0149ffd9ba008864da77fb46f7a3e50e 100644
--- a/interface.lisp
+++ b/interface.lisp
@@ -27,7 +27,7 @@
    #:operation #:make-operation #:find-operation
    #:upward-operation #:downward-operation #:sideway-operation #:selfward-operation
                       #:non-propagating-operation
-   #:build-op #:build #:build-system
+   #:build-op #:build
    #:load-op #:prepare-op #:compile-op
    #:prepare-source-op #:load-source-op #:test-op
    #:feature #:version #:version-satisfies #:upgrade-asdf
diff --git a/operate.lisp b/operate.lisp
index 999b9510b86fd9e4d3a06945f72e8dcd601883bb..be4b948ba5ecd6910eced58b7f74166a13fd2ff7 100644
--- a/operate.lisp
+++ b/operate.lisp
@@ -9,7 +9,7 @@
   (:export
    #:operate #:oos
    #:*systems-being-operated*
-   #:build-op #:build #:build-system
+   #:build-op #:build
    #:load-system #:load-systems #:load-systems*
    #:compile-system #:test-system #:require-system
    #:*load-system-operation* #:module-provide-asdf
@@ -130,10 +130,6 @@ to load it in current image."
     (apply 'operate 'build-op system keys)
     t)
 
-  (defun build-system (system &rest keys)
-    "Alias for function BUILD"
-    (apply 'build system keys))
-
   (defun load-system (system &rest keys &key force force-not verbose version &allow-other-keys)
     "Shorthand for `(operate 'asdf:load-op system)`. See OPERATE for details."
     (declare (ignore force force-not verbose version))