I’d like to propose that we add support for setting additional compile flags in patch builds for the server, sys-perf, and performance projects by way of https://github.com/evergreen-ci/evergreen/wiki/Parameterized-Builds. Right now if I want to patch build a change to a compile flag, I either need to make a source code edit to the build system to make a flag I want to enable on by default, or I need to edit the yaml file to add the new flag to the declared compile flags. That’s not so bad for a one off test, but it makes it hard to script a whole bunch of experiments. Additionally, local edits have a risk of getting pushed.