Are idempotent builds possible?

[jakehow]

@jakehow

On containers:

I think we could probably get our app to build on CI as well, but we would do so by dropping docker features that we want to use in development and do easily for every other app we work with.

My checklist is:

Use the ‘standard’ docker tools for dev on OS X. (docker-machine, docker-compose, boot2docker, virtualbox) Mount my application code as a volume so I can edit it on my host machine (Mac) Ability to cache dependencies so that I dont need to redo npm/bower install build step when I only change app code. Build in a similar timeframe to building on the host machine.

If anyone has a Dockerfile they can share that achieves this that would be awesome. The specific hurdles we have seen are around virtualbox filesystem being very slow with the number of symlinks created while running ember server, and the inability to mount our application code because of the inclusion of node_modules and bower_components within the project path. File system events also do not get triggered within the container so we need to use --watcher=polling but that seems OK to me.

Moved this discussion here since it is a separate issue.