How to use homebrew to install old Elixir versions?

I’m no help with brew, but I’ve been a happy user of kiex for some time now. It builds from source and allows you to seamless switch versions. You might consider it instead of brew, which would let you simply do kiex install 1.3.4

https://github.com/taylor/kiex

Homebrew does not keep older versions for all of their packages. Elixir is one of those where there aren’t older versions. You can look for older packages like this: brew search [packagename]. If there are older versions, they’ll pop up.

Thanks folks, I’ll give a shot at kiex then.

So for change the version it’s needed to use a manager?
I already have installed with brew and for use diferent versions I install right now the asdf.
It’s very simple this manager and I liked.
My question is, I need to uninstall the elixir and Erlang with homebrew?
Or just keep them? Because I know it’s a lot capacity keep them.

Installing older versions of Elixir for testing package compatibility has proved surprisingly hard in 2025. After fighting brew and asdf failing installs/builds, kiex works seamlessly. Thanks for the direction Chris (and of course, for all your incredible work on Phoenix)

Worth noting that compatibility between Elixir AND Erlang version seems very relevant here – many combinations won’t work at all. It took a bit of flailing before I realized I needed to downgrade Erlang as well after consulting the compatibility table here: Compatibility and deprecations — Elixir v1.20.2. Fortunately homebrew hosts at least some older versions of Erlang (no such luck for elixir).

What specifically you couldn’t make work with asdf? Theoretically this is the best option as it compiles OTP from source.

I didn’t intend to disparage asdf, I’m just not a user of it at present so there are likely some familiarity gaps. The tests kept failing after installing older Elixir versions, which in retrospect may have been happening because I didn’t have the correct/compatible versions of Erlang installed (the test failure output didn’t help point me in any useful direction, unfortunately). I couldn’t find a way to skip the tests, which seemed to abort the whole install when they fail. Even after I did get an install to pass (1.16 I think, only one that worked) and added some incantations to my .bashrc, the elixir command would do nothing, no output, not even “command not found.” I’m sure this was due to some form of user error, but after trying out kiex no problems like these appeared, and I was up and running in a couple minutes. At a certain point the time for troubleshooting is up, and the path of least resistance is what you need to run with.

I’d be happy to try all this again and open a github issue or two (for anything that doesn’t prove to be user error) if that’s helpful at all.