problem asynchronizing ecto calls

This problem is particularly annoying for me since I use SQLite in one of the environments, which doesn’t have an Ecto 3 adapter yet. I really want to update the dependencies but am not able to. For now I have to comment out my test.

I wonder if there is an easy way to use different versions of a package depending on different environments. It seems the only way to do so would be to keep different lockfiles in the project directory?