Mox

The overall lack of typing in elixir is prone to your requests responses not being completely accurate. XVCR where you know you at least have a snapshot of the API at a time and maybe like generally how I approach testing it is like have the client itself the the lowest layer of your HTTP request be tested using XVCR. When I need to go that deep I can go further and use bypass or in some project I have a custom plug server which I start myself inside the suite okay so I can have a real query sometimes with SSL to test the stack right from beginning to end.