[jake_morrison]

You can do something similar with docker compose, driving the system from the outside. Create dockerized versions of dependencies like the database, build and run tests, and then run tests against the production app container. It's particularly useful for testing a set of microservices.

See https://github.com/cogini/phoenix_container_example for a full example. This blog post describes it in detail: https://www.cogini.com/blog/breaking-up-the-monolith-buildin...

[m00x]

We use docker environments like this for tests, but it does have its issues.

You often need to add custom behavior like waiting for the app to load and start serving, healthchecks, etc. Having it all in code is pretty useful, and it's self-contained within the code itself vs having to set up the environment in different places (CI, Github actions, local dev, etc).

The negative is that code isn't portable to prod, it doesn't test your environment as well (important for staging), and you're missing out on sharing some environment settings.

I feel like it definitely has its place in the stack and in certain companies.