In #153 @paulb-elastic discovered that the docs only work in the rather common scenario where the your user on the host machine is 1000 which matches the heartbeat user in the container. The issue, essentially, is that the heartbeat user in docker has a uid of 1000, and if this doesn't match up with the uids of the shared mounts you'll get perms issues.

Possible solutions:

1. Document this, recommend users users change their local file perms
2. Start using fixuid in the container
3. Something else???