Tools I Love: mise (mise-en-place)

I'm a bit of a polyglot engineer these days. Most days I write Swift, but there's days I write JavaScript or Ruby or Go or whatever language du jour. Most programming languages and their toolchains share a similar pattern: there's some command line binary you'll need to run to compile/run/interpret your code.

$ node someJavaScriptFile.js
$ ruby some_ruby_file.rb
$ swift run SomeSwiftPackage

These work just fine if you're working solo from your local developer environment. You do some brew install or download some installer for the toolchain from the official website, and you're off running.

#brew install my-tool@v???

A new version of your toolchain is released, and you brew upgrade my-tool to get the latest version. This works great until you realize your CI/CD or deployment environment is on an older version, or some package of yours isn't ready yet, so you'll need to go back to the previous version.

Easy enough to do brew install my-tool@v1, right?

Except now my-tool is on version 1.0 everywhere across your computer, and your client's project is actually on my-tool@v2 already.

You swap between versions by doing a brew uninstall my-tool@v1 && brew install my-tool@v2 in the morning to do your client work.

You swap back with a brew uninstall my-tool@v2 && brew install my-tool@v1 in the evening to do your personal work.

Pure madness. 😩

#One tool to rule them all

mise (aka mise-en-place) helps you manage multiple versions of your toolchains through a few mechanisms:

• Global versions: the default version for your development environment, regardless of current directory.
• Project versions: the resolved version for a given project, based on the existence of a mise.toml file in the directory tree.
• Idiomatic version files: language-specific files like .ruby-version, .nvmrc, .go-version, etc.

Each of these versions coalesce into a set of toolchain versions that are automatically available on your $PATH just by changing directories. It's magical.

#"I've used asdf/nvm/rbenv before, this is nothing new."

Yes yes yes, of course. I used asdf for years too. But what's great about mise is that it Just Works™ for nearly every language or toolchain that I've encountered, without needing to install Yet Another Version Manager.

Over my career, I've used mise with everything from Go, Node, Ruby, .NET and C#, Java, and Rust. 99.9% of the time, mise works right out of the box. Even when my work project needed to have a different .NET SDK version versus the .NET runtime version, a handful of symlinks between mise's isolated installs made it easy to jump between projects that had awkward setups.

Of the tools I rely on in my development environment, mise has become one of the first I install, and one I can rely on out of the box.

Next time you go to brew install some programming language or toolchain, think twice, and use mise instead.