The current implementation of the stitch support lib tasks are split into two task groups:

https://github.com/mongodb/mongo/blob/20f37580bdf89817db398c477d619627ce1feef7/etc/evergreen.yml#L8402-L8413

The first task group does the build and archive part, and then the second does the build and run of the tests.

While this works, it isn't ideal. Because they are separate task groups, they can run independently on separate machines. This causes the second task groups build of the tests to basically rebuild the whole library.

It would be better if this was just one task group with the three activity set to run serially on one machine.