diff --git a/requirements/requirements-check.txt b/requirements/requirements-check.txt
index 1171249c..010d088c 100644
--- a/requirements/requirements-check.txt
+++ b/requirements/requirements-check.txt
@@ -11,4 +11,7 @@ mypy
 # version of pytest will do.
 pytest
 types-colorama
-time-machine
\ No newline at end of file
+time-machine
+
+# Required
+build
\ No newline at end of file