mise/Environment

• Environments | mise-en-place

  • What are two ways to set EnvVars with mise? card

    • 1 - In mise/Config/mise.toml/env

      • toml

        [env]
        NODE_ENV = 'production'

    • 2 - with mise/set

      • mise set NODE_ENV=development

  • What are two ways to unset EnvVars with mise? card

    • 1 - In mise/Config/mise.toml/env

      • toml

        [env]
        NODE_ENV = false # unset a previously set NODE_ENV

      • My Notes
        • It's a bit Astonishing to me that we can unset environment variables with this technique
        • See also TOML/Q/Is false a first-class primitive.

    • 2 - with mise/unset

      • mise unset NODE_ENV

  • How do I view declared EnvVars? card

    • with mise/set

      • mise set
        # key       value        source
        # NODE_ENV  development  mise.toml

      • My Notes
        • This is also a bit Astonishing to me; I would expect mise list or something similar

  • What are the 4 ways that EnvVars declared in a mise/Config/mise.toml can be used/expressed in mise? card

    • 1 - in mise/exec with a shell command

      • sh

        mise set MY_VAR=123
        mise exec -- bash -c 'echo $MY_VAR'
        # 123

    • 2 - when invoking a mise/Tool

      • 2.1 via mise/exec

        • My Notes AFAIK it's not possible to make a tool-specific EnvVar unless one wraps it in a mise/Task, (unfortunately, IMO)
        • sh

          mise use node@26
          mise set MY_VAR=123
          cat mise.toml
          # [tools]
          # node = '24'
          # [env]
          # MY_VAR = '123'
          mise exec -- node --eval 'console.log(process.env.MY_VAR)'
          # 123

      • 2.2 - in the shell, after mise/activate

        • As long as your zsh/.zshrc, Bash/.bashrc etc has eval "$(mise activate zsh)" in it, any declared environment variables will be available
        • sh

          $> cd /path/to/project
          $> mise set NODE_ENV=production
          $> cat mise.toml
          # [env]
          # NODE_ENV = 'production'
          
          $> echo $NODE_ENV
          # production

      • 2.3 - when using a mise/Shim'd version of a mise/Tool

        • If, instead of using mise activate in one's zshrc shell, one is using mise shims, whereby tools are symlinks that are configured to point to the executable that's been configured to have the mise environment, then the declared mise environment will be available to that binary
        • sh

          mise set NODE_ENV=production
          mise use node@26
          # using the absolute path for the example
          ~/.local/share/mise/shims/node --eval 'console.log(process.env.NODE_ENV)'

    • 3 - in mise/tasks, including per-task env-vars

      • you can modify environment variables just for a particular mise task.
      • Here's an example of a mise/Task/TOML version of this, but it's also possible in mise/Task/File
        • toml

          [tasks.print]
          run = "echo $MY_VAR"
          env = { _.file = '/path/to/file.env', "MY_VAR" = "my variable" }

    • 4 - after calling mise/en to activate just mise's declared environment vars

      • The mise en command is perhaps comparable to activating a Py/Virtualenv; subsequent commands make use of certain set environment variables.
      • sh

        mise set FOO=bar
        mise en
        echo $FOO
        # bar