diff --git a/build.sh b/build.sh
index 34e4b1153..f790077e3 100755
--- a/build.sh
+++ b/build.sh
@@ -3,10 +3,16 @@
 # Put installed packages into ./bin
 export GOBIN=$PWD/`dirname $0`/bin
 
-export BRANCH=`(git symbolic-ref --short HEAD | cut -d'/' -f 3 )|| ""`
-export BUILD=`git rev-parse --short HEAD || ""`
+if [ -d ".git" ] 
+then
+    export BUILD=`git rev-parse --short HEAD || ""`
+    export BRANCH=`(git symbolic-ref --short HEAD | tr -d \/ ) || ""`
+    [[ $BRANCH == "master" ]] && export BRANCH=""
 
-export FLAGS="-X github.com/matrix-org/dendrite/internal.branch=$BRANCH -X github.com/matrix-org/dendrite/internal.build=$BUILD"
+    export FLAGS="-X github.com/matrix-org/dendrite/internal.branch=$BRANCH -X github.com/matrix-org/dendrite/internal.build=$BUILD"
+else
+    export FLAGS=""
+fi
 
 go install -trimpath -ldflags "$FLAGS" -v $PWD/`dirname $0`/cmd/...