Problem creating new directory on build container

Part of our build creates and runs some tests using Lucene indexes, which are stored on the filesystem. However, it seems that my application can’t create the directory. I get denied trying to create /var/foo/lucene/indexes, which causes my application to fail to start.

This is a java application running on the Ubuntu 14.04 (Trusty) build environment.

Does CircleCI not allow the creation of that directory? Is there a suggested way to handle situations like this in CircleCI?

I would try using circle.yml to setup the directory beforehand to see if it helps.