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Comment by geraneum | Hacker News Reader

In reality, when using Docker, Dev and Prod are almost never the same. We usually install different packages in Dev image i.e. debuggers or linters, we try to optimize the heck out of the Prod image, thus using a different build of the base image, etc. And all this, when you are only developing on Linux for Linux.

I’m not saying this is the right way but this is very common. I also agree with the rest of your points.

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Yes, I agree. I'm working on a Rails project today and the container in development has some gems we only use for development and testing: byebug, pry, rspec, timecop, simplecov, factory_bot. They won't go into the production images. The instructions for developers are

    docker-compose build
    docker-compose run --rm api bundle
    docker-compose up

api is the name of the service in docker-compose.yml

One developer has a M1 Mac and he's using something called mutagen instead of docker. His docker-compose.yml is a little different and he's paying a performance penalty. His M1 is only 50% faster than my Intel from 2014 at running the test suite (50 seconds vs 75.) The difference is not noticeable when running only a few tests per time when working on a single feature.

You probably want to use

    docker compose

not

    docker-compose

The latter was the name of the compose v1 binary, so using it may cause your command to be handled with a v1-to-v2 compatibility mode. Depends on how your installation is setup. Compose v2 is implemented as a Docker CLI plugin.

When I invoke `docker compose up` on my project with Docker version 20.10.18 it says:

    The new 'docker compose' command is currently experimental.

I'm not sure what that means, but I don't think compose v2 is considered experimental at this point. It is included in Docker Desktop, for example. You might be running an older version. You can check `docker compose version`. Version 2.12.2 was released a few days ago.

Does he run ARM docker images or X86? I can imagine the latter will slow things down

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