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File Tasks

docs/tasks/file-tasks.md

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File Tasks

In addition to defining tasks through the configuration, they can also be defined as standalone script files in one of the following directories:

  • mise-tasks/:task_name
  • .mise-tasks/:task_name
  • mise/tasks/:task_name
  • .mise/tasks/:task_name
  • .config/mise/tasks/:task_name

These are the default file-task directories. If task_config.includes is set for the current config scope, mise searches only the paths listed there instead.

Here is an example of a file task that builds a Rust CLI:

bash
#!/usr/bin/env bash
#MISE description="Build the CLI"
cargo build

::: tip Important Ensure that the file is executable, otherwise mise will not be able to detect it.

shell
chmod +x mise-tasks/build

On Windows there is no permission bit to set, and chmod is not the answer there — see Windows for what makes a file task detectable instead. :::

Having the code in a bash file and not TOML helps make it work better in editors since they can do syntax highlighting and linting more easily.

They also still work great for non-mise users—though of course they'll need to find a different way to install their dev tools the tasks might use.

Task Configuration

All configuration options can be found here task configuration You can provide additional configuration for file tasks by adding #MISE comments at the top of the file.

bash
#MISE description="Build the CLI"
#MISE alias="b"
#MISE sources=["Cargo.toml", "src/**/*.rs"]
#MISE outputs=["target/debug/mycli"]
#MISE env={RUST_BACKTRACE = "1"}
#MISE depends=["lint", "test"]
#MISE tools={rust="1.50.0"}

Assuming that file was located in mise-tasks/build, it can then be run with mise run build (or with its alias: mise run b).

Multi-line values

Each #MISE line is TOML. An array or inline table may be split across several lines as long as every line keeps the #MISE prefix, which keeps long depends/sources lists readable:

bash
#!/usr/bin/env bash
#MISE description="Build the CLI"
#MISE depends=[
#MISE   "lint",
#MISE   "test",
#MISE ]
#MISE sources=[
#MISE   "Cargo.toml",
#MISE   "src/**/*.rs",
#MISE ]
cargo build

A table can also be built up by repeating the prefix with dotted keys, which avoids the surrounding braces entirely:

bash
#MISE tools.node="20"
#MISE tools.python="3.11"

Mise provides file tasks with project context variables such as MISE_PROJECT_ROOT, which identifies the project root regardless of the directory from which the task is invoked. See Tasks for the complete list of variables.

:::tip Beware of formatters changing #MISE to # MISE. It's intentionally ignored by mise to avoid unintentional configuration. To workaround this, use the alternative: # [MISE]. :::

Shebang

The shebang line is optional, but if it is present, it will be used to determine the shell to run the script with. You can also use it to run the script with various programming languages.

::: code-group

js
#!/usr/bin/env node
//MISE description="Hello, World in Node.js"

console.log("Hello, World!");
python
#!/usr/bin/env python
#MISE description="Hello, World in Python"

print('Hello, World!')
ts
#!/usr/bin/env -S deno run --allow-env
//MISE description="Hello, World in Deno"

console.log(`PATH, ${Deno.env.get("PATH")}`);
powershell
#!/usr/bin/env pwsh
#MISE description="Hello, World in PowerShell"

$current_directory = Get-Location
Write-Host "Hello from PowerShell, current directory is $current_directory"

:::

Windows

Windows has no execute permission for mise to look at, so it decides whether a file is a task a different way. A file is a task if either holds:

The two answer different questions. The extension means Windows itself can run the file; the shebang means mise can work out an interpreter for it. Windows does not implement shebangs — mise reads the line and starts the interpreter itself — which is why a .sh script, or a file with no extension at all, is still a task there as long as it has one.

The practical consequence is that a file with neither is invisible on Windows even though it works on Linux and macOS:

bash
# no shebang, no extension -> not a task on Windows
cargo build

Adding #!/usr/bin/env bash is usually all it takes, and it costs nothing on the other platforms.

Writing one task for both platforms

File tasks have no equivalent of a TOML task's run_windows — the script is the command, so there is nowhere to put a second one. Write the two scripts side by side instead, giving the Windows one an executable extension:

mise-tasks/
  build.sh       # #!/usr/bin/env bash
  build.ps1      # the Windows version

The two have to share a directory and a stem — that pairing is what makes them one task rather than two that happen to be named alike.

On Windows mise prefers the native script: build.ps1 answers to build, and the POSIX one is dropped. On Linux and macOS the .ps1 has no execute permission, so only build.sh is found. mise run build does the right thing on each.

The POSIX half is anything without one of the windows_executable_extensions, so a file with no extension at all works the same way:

mise-tasks/
  build          # #!/usr/bin/env bash
  build.ps1      # the Windows version

Marking the .ps1 executable on Linux or macOS does not break that — it simply appears there as a separate task called build.ps1, since the rename to build only happens on Windows.

If you would rather name the two files something unrelated, or say which is which explicitly, use a TOML task that calls them:

toml
[tasks.build]
run = "./scripts/build.sh"
run_windows = "pwsh -File ./scripts/windows-build.ps1"

Spelled out rather than ./scripts/windows-build.ps1, because windows_default_inline_shell_args defaults to cmd /c, and cmd will not start a .ps1 on its own.

If there is more than one Windows candidate — say build.ps1 and build.cmd — mise cannot choose between them, so it leaves everything alone: all three files stay, listed as build.sh, build.ps1 and build.cmd.

Editing tasks

This script can be edited by running mise tasks edit build (using $EDITOR). If it doesn't exist it will be created. This is convenient for quickly editing or creating new scripts.

Task Grouping

File tasks in mise-tasks, .mise/tasks, mise/tasks, or .config/mise/tasks can be grouped into sub-directories which will automatically apply prefixes to their names when loaded.

Example: With a folder structure like below:

text
mise-tasks
├── build
└── test
    ├── _default
    ├── integration
    └── units

Running mise tasks will give the below output:

shellsession
$ mise tasks
Name              Description Source
build                         ./mise-tasks/build
test                          ./mise-tasks/test/_default
test:integration              ./mise-tasks/test/integration
test:units                    ./mise-tasks/test/units

Arguments

::: tip For comprehensive information about task arguments, see the dedicated Task Arguments page. :::

usage spec can be used within these files to provide argument parsing, autocompletion, documentation when running mise and can be exported to markdown. Essentially this turns tasks into fully-fledged CLIs.

:::tip The usage CLI is not required to execute mise tasks with the usage spec. However, for completions to work, the usage CLI must be installed and available in the PATH. :::

Example file task with arguments

Here is an example of a file task that builds a Rust CLI using some of the features of usage:

bash
#!/usr/bin/env bash
set -e

#USAGE flag "-c --clean" help="Clean the build directory before building"
#USAGE flag "-p --profile <profile>" help="Build with the specified profile" default="debug" {
#USAGE   choices "debug" "release"
#USAGE }
#USAGE flag "-u --user <user>" help="The user to build for"
#USAGE complete "user" run="mycli users"
#USAGE arg "<target>" help="The target to build"

if [ "${usage_clean:-false}" = "true" ]; then
  cargo clean
fi

cargo build --profile "${usage_profile?}" --target "${usage_target?}"

::: tip For details on bash parameter expansion patterns like ${var?}, ${var:-default}, and ${var:+value}, see Bash Variable Expansion for Usage Variables. :::

If you have installed usage, completions will be enabled for your task. In this example,

  • mise run -- build --profile <tab><tab> will show debug and release as options.
  • The --user flag will also show completions generated by the output of mycli users.
  • Note: Use -- to separate mise flags from task arguments: mise run -- build --profile release <target>

(Note that cli and markdown help for tasks is not yet implemented in mise as of this writing but that is planned.)

:::tip If you don't get any autocomplete suggestions, use the -v (verbose) flag to see what's going on. For example, if you use mise run build -v and have an invalid usage spec, you will see an error message such as DEBUG failed to parse task file with usage :::

Environment variable backing

Arguments and flags can be backed by environment variables with env="...". The precedence order is CLI argument, environment variable, then default value:

bash
#!/usr/bin/env bash
#MISE description="Deploy application"
#USAGE arg "[environment]" env="DEPLOY_ENV" default="development"
#USAGE flag "--region <region>" env="AWS_REGION" default="us-east-1"

echo "Deploying to ${usage_environment} in ${usage_region}"

This lets the same file task work with either explicit arguments or the environment of the calling shell:

shell
DEPLOY_ENV=staging AWS_REGION=us-west-2 mise run deploy

See Environment Variable Backing for more details.

Example of a NodeJS file task with arguments

Here is how you can use usage to parse arguments in a Node.js script:

js
#!/usr/bin/env -S node
//MISE description="Write a greeting to a file"
//USAGE flag "-f --force" help="Overwrite existing <file>"
//USAGE flag "-u --user <user>" help="User to run as"
//USAGE arg "<output_file>" help="The file to write" default="file.txt" {
//USAGE   choices "greeting.txt" "file.txt"
//USAGE }

const fs = require("fs");

const { usage_user, usage_force, usage_output_file } = process.env;

if (usage_force === "true") {
  fs.rmSync(usage_output_file, { force: true });
}

const user = usage_user ?? "world";
fs.appendFileSync(usage_output_file, `Hello, ${user}\n`);
console.log(`Greeting written to ${usage_output_file}`);

Run it with:

shell
mise run greet greeting.txt --user Alice
# Greeting written to greeting.txt

If you pass an invalid argument, you will get an error message:

shell
mise run greet invalid.txt --user Alice
# [greet] ERROR
#   0: Invalid choice for arg output_file: invalid.txt, expected one of greeting.txt, file.txt

Autocomplete will show the available choices for the output_file argument if usage is installed.

shell
mise run greet <TAB>
# > greeting.txt
#   file.txt

CWD

mise sets the current working directory to the directory of mise.toml before running tasks. This can be overridden by setting <span v-pre>dir="{{cwd}}"</span> in the task header:

bash
#!/usr/bin/env bash
#MISE dir="{{cwd}}"

Also, the original working directory is available in the MISE_ORIGINAL_CWD environment variable:

bash
#!/usr/bin/env bash
cd "$MISE_ORIGINAL_CWD"

Running tasks directly

Tasks don't need to be configured as part of a config, you can just run them directly by passing the path to the script:

bash
mise run ./path/to/script.sh

Note that the path must start with / or ./ to be considered a file path. (On Windows it can be C:\ or .\)