There’s another option now: update your deps and it should just work - Plataformatec on X: "We have just released DBConnection v2.0.4 (which powers Ecto) to use Elixir's v1.8 task callers feature. This means using the SQL Sandbox to test code that uses tasks for concurrency should work out of the box - and it should work concurrently too (wow, such concurrency)!" / X
