diff --git a/docs/guides/building_in_docker.md b/docs/guides/building_in_docker.md
index 9e84c2c4..0d3a8b48 100644
--- a/docs/guides/building_in_docker.md
+++ b/docs/guides/building_in_docker.md
@@ -59,11 +59,11 @@ First, our build script, in `bin/build`, would look something like this:
 
 set -e
 
+cd /opt/build
+
 APP_NAME="$(grep 'app:' mix.exs | sed -e 's/\[//g' -e 's/ //g' -e 's/app://' -e 's/[:,]//g')"
 APP_VSN="$(grep 'version:' mix.exs | cut -d '"' -f2)"
 
-cd /opt/build
-
 mkdir -p /opt/build/rel/artifacts
 
 # Install updated versions of hex/rebar