Discusses an alternative strategy to managing external code that is included in a version control repository to both git submodules (which we don't use) and Piston (which we do). Putting here as something to consider for future replacement of use of Piston.

The disadvantage is that the process, mainly number of commands and their amount of flags to them to use, is more complex than Piston.

Advantages are:

gets rid of an external dependency since we already use git and we wouldn't need an additional tool
has the ability to push changes (i.e. our local patches) to upstream repository for the external code project that we rely on

The second advantage may make it less likely that our code changes for external projects get submitted to those external projects.