diff --git a/xbps-src b/xbps-src
index 06970629cc..ecd389b93e 100755
--- a/xbps-src
+++ b/xbps-src
@@ -634,7 +634,8 @@ export XBPS_SHUTILSDIR XBPS_CROSSPFDIR XBPS_TRIGGERSDIR \
     XBPS_KEEP_ALL XBPS_HOSTDIR XBPS_MASTERDIR XBPS_SRC_VERSION \
     XBPS_DESTDIR XBPS_MACHINE XBPS_TEMP_MASTERDIR XBPS_BINPKG_EXISTS \
     XBPS_LIBEXECDIR XBPS_DISTDIR XBPS_DISTFILES_MIRROR XBPS_ALLOW_RESTRICTED \
-    XBPS_USE_GIT_COMMIT_DATE XBPS_PKG_COMPTYPE XBPS_REPO_COMPTYPE XBPS_BUILDHELPERDIR
+    XBPS_USE_GIT_COMMIT_DATE XBPS_PKG_COMPTYPE XBPS_REPO_COMPTYPE \
+    XBPS_BUILDHELPERDIR XBPS_USE_BUILD_MTIME
 
 for i in REPOSITORY DESTDIR BUILDDIR SRCDISTDIR; do
     eval val="\$XBPS_$i"