diff --git a/build-go.sh b/build-go.sh
index 6834738..e2b6522 100755
--- a/build-go.sh
+++ b/build-go.sh
@@ -1,6 +1,10 @@
 #!/bin/bash
 
 set -e
+if [ ${EUID} -ne 0 ]; then
+  echo "error: this script must be run as root" 1>&2
+  exit 1
+fi
 
 GITHUB="https://github.com/golang/go/archive/"
 
@@ -31,6 +35,12 @@ cd ${INSTALL}/${V14}/src
 
 export GOROOT_BOOTSTRAP=${INSTALL}/${V14}
 
+if [ "$(uname -m)" == "x86_64" ]; then
+  export GOARCH=386
+else
+  export GOARCH=amd64
+fi
+
 cd ${INSTALL}/${Vnew}/src
 ./make.bash &> /dev/null
 
@@ -45,6 +55,7 @@ echo "add this to your .bashrc/.profile:"
 echo ""
 echo "export CGO_ENABLED=0"
 echo "export GOPATH=~/go"
+echo "export GOROOT=/usr/local/go"
 echo "export PATH=\${PATH}:${GOROOT}"
 echo ""