diff --git a/hack/lib/golang.sh b/hack/lib/golang.sh
index 0192b70167..f6ec18ef98 100755
--- a/hack/lib/golang.sh
+++ b/hack/lib/golang.sh
@@ -163,6 +163,8 @@ kube::golang::dedup() {
 # to readonly.
 # The configured vars will only contain platforms allowed by the
 # KUBE_SUPPORTED* vars at the top of this file.
+declare -a -g KUBE_SERVER_PLATFORMS
+declare -a -g KUBE_CLIENT_PLATFORMS
 kube::golang::setup_platforms() {
   if [[ -n "${KUBE_BUILD_PLATFORMS:-}" ]]; then
     # KUBE_BUILD_PLATFORMS needs to be read into an array before the next
@@ -202,20 +204,23 @@ kube::golang::setup_platforms() {
     readonly KUBE_CLIENT_PLATFORMS
 
   elif [[ "${KUBE_FASTBUILD:-}" == "true" ]]; then
-    readonly KUBE_SERVER_PLATFORMS=(linux/amd64)
+    KUBE_SERVER_PLATFORMS=(linux/amd64)
+    readonly KUBE_SERVER_PLATFORMS
     readonly KUBE_NODE_PLATFORMS=(linux/amd64)
     if [[ "${KUBE_BUILDER_OS:-}" == "darwin"* ]]; then
       readonly KUBE_TEST_PLATFORMS=(
         darwin/amd64
         linux/amd64
       )
-      readonly KUBE_CLIENT_PLATFORMS=(
+      KUBE_CLIENT_PLATFORMS=(
         darwin/amd64
         linux/amd64
-      )
+      ) 
+      readonly KUBE_CLIENT_PLATFORMS
     else
       readonly KUBE_TEST_PLATFORMS=(linux/amd64)
-      readonly KUBE_CLIENT_PLATFORMS=(linux/amd64)
+      KUBE_CLIENT_PLATFORMS=(linux/amd64)
+      readonly KUBE_CLIENT_PLATFORMS
     fi
   else
     KUBE_SERVER_PLATFORMS=("${KUBE_SUPPORTED_SERVER_PLATFORMS[@]}")