diff --git a/build.sh b/build.sh
index ab9791ee18..d1d3a4866a 100755
--- a/build.sh
+++ b/build.sh
@@ -17,7 +17,7 @@ board=$1
 target=${*:2}
 cd $(dirname $0)
 basedir=$(pwd)
-gzip=$(which pigz || which gzip)
+gzip=$(which pigz 2> /dev/null || which gzip 2> /dev/null)
 
 # extra environment from local file
 test -f $basedir/.build-env && source $basedir/.build-env
@@ -26,14 +26,14 @@ test -f $basedir/.build-env && source $basedir/.build-env
 if [ -n "$THINGOS_SHORT_NAME" ]; then
     osname=$THINGOS_SHORT_NAME
 else
-    osname=$(source $basedir/board/common/overlay/etc/version && echo $os_short_name)
+    osname=$(source $basedir/board/common/overlay/etc/version && echo $OS_SHORT_NAME)
 fi
 
 # OS version
 if [ -n "$THINGOS_VERSION" ]; then
     osversion=$THINGOS_VERSION
 else
-    osversion=$(source $basedir/board/common/overlay/etc/version && echo $os_version)
+    osversion=$(source $basedir/board/common/overlay/etc/version && echo $OS_VERSION)
 fi
 
 # when the special "boards" keyword is used for board, simply list all known boards