Prepare experimental

The mise prepare command ensures project dependencies are ready by checking if lockfiles are newer than installed outputs (e.g., package-lock.json vs node_modules/) and running install commands if needed.

Quick Start

# Enable experimental features
export MISE_EXPERIMENTAL=1

# Run all applicable prepare steps
mise prepare

# Or use the alias
mise prep

Configuration

Configure prepare providers in mise.toml:

# Built-in npm provider (auto-detects lockfile)
[prepare.npm]
auto = true  # Auto-run before mise x/run

# Built-in providers for other package managers
[prepare.yarn]
[prepare.pnpm]
[prepare.bun]
[prepare.go]
[prepare.pip]
[prepare.poetry]
[prepare.uv]
[prepare.bundler]
[prepare.composer]

# Custom provider
[prepare.codegen]
auto = true
sources = ["schema/*.graphql"]
outputs = ["src/generated/"]
run = "npm run codegen"

# Disable specific providers
[prepare]
disable = ["npm"]

Built-in Providers

mise includes built-in providers for common package managers:

Provider	Sources	Outputs	Command
npm	package.json, package-lock.json	node_modules/	npm install
yarn	package.json, yarn.lock	node_modules/	yarn install
pnpm	package.json, pnpm-lock.yaml	node_modules/	pnpm install
bun	package.json, bun.lock, bun.lockb	node_modules/	bun install
go	go.mod	vendor/ or go.sum	go mod vendor or go mod download
pip	requirements.txt	.venv/	pip install -r requirements.txt
poetry	pyproject.toml, poetry.lock	.venv/	poetry install
uv	pyproject.toml, uv.lock	.venv/	uv sync
bundler	Gemfile, Gemfile.lock	vendor/bundle/	bundle install
composer	composer.json, composer.lock	vendor/	composer install

Built-in providers are only active when explicitly configured in mise.toml and their lockfile exists.

Custom Providers

Create custom providers for project-specific build steps:

[prepare.codegen]
sources = ["schema/*.graphql", "codegen.yml"]
outputs = ["src/generated/"]
run = "npm run codegen"
description = "Generate GraphQL types"

[prepare.prisma]
sources = ["prisma/schema.prisma"]
outputs = ["node_modules/.prisma/"]
run = "npx prisma generate"

Provider Options

Option	Type	Description
auto	bool	Auto-run before mise x and mise run (default: false)
sources	string[]	Files/patterns to check for changes
outputs	string[]	Files/directories that should be newer than sources
run	string	Command to run when stale
env	table	Environment variables to set
dir	string	Working directory for the command
description	string	Description shown in output
touch_outputs	bool	Touch output mtimes after a successful run so they appear fresh (default: true)
depends	string[]	Other provider names that must complete before this one runs
timeout	string	Timeout for the run command, e.g., "30s", "5m" (default: no timeout)

Freshness Checking

mise uses modification time (mtime) comparison to determine if outputs are stale:

1. Find the most recent mtime among all source files
2. Find the most recent mtime among all output files
3. If any source is newer than all outputs, the provider is stale

This means:

• If you modify package-lock.json, node_modules/ will be considered stale
• If node_modules/ doesn't exist, the provider is always stale
• If sources don't exist, the provider is considered fresh (nothing to do)

After a successful run, mise touches the mtime of each output to now (controlled by touch_outputs, default true). This ensures that commands which are no-ops when dependencies are already satisfied (e.g. uv sync when the venv is up to date) still mark outputs as fresh, preventing repeated stale warnings on subsequent invocations.

Auto-Prepare

When auto = true is set on a provider, it will automatically run before:

• mise run (task execution)
• mise x (exec command)

This ensures dependencies are always up-to-date before running tasks or commands.

To skip auto-prepare for a single invocation:

mise run --no-prepare build
mise x --no-prepare -- npm test

Staleness Warnings

When using mise activate, mise will warn you if any auto-enabled providers have stale dependencies:

mise WARN prepare: npm may need update, run `mise prep`

This can be disabled with:

[settings]
status.show_prepare_stale = false

CLI Usage

# Run all applicable prepare steps
mise prepare

# Run only a specific provider
mise prepare npm

# Show why a provider is fresh or stale
mise prepare npm --explain

# Show what would run without executing
mise prepare --dry-run

# Force run even if outputs are fresh
mise prepare --force

# List available prepare providers
mise prepare --list

# Skip specific providers
mise prepare --skip npm

Dependencies

Providers can declare dependencies on other providers using the depends field. A provider will wait for all its dependencies to complete successfully before running.

[prepare.uv]
auto = true

[prepare.ansible-galaxy]
auto = true
depends = ["uv"]
run = "ansible-galaxy install -f requirements.yml"
sources = ["requirements.yml"]
outputs = [".galaxy-installed"]

In this example, ansible-galaxy will wait for uv to finish before starting.

Providers without depends run in parallel as before. If a dependency fails, all providers that depend on it are skipped. Circular dependencies are detected and the affected providers are skipped with a warning.

Parallel Execution

Prepare providers run in parallel, respecting the jobs setting for concurrency limits. This speeds up preparation when multiple providers need to run (e.g., both npm and pip). Providers with depends will wait for their dependencies to complete before starting, while independent providers run concurrently.

[settings]
jobs = 4  # Run up to 4 providers in parallel

Example: Full-Stack Project

# mise.toml for a project with Node.js frontend and Python backend

[prepare.npm]
auto = true

[prepare.poetry]
auto = true

[prepare.prisma]
auto = true
depends = ["npm"]  # needs node_modules first
sources = ["prisma/schema.prisma"]
outputs = ["node_modules/.prisma/"]
run = "npx prisma generate"

[prepare.frontend-codegen]
depends = ["npm"]  # needs node_modules first
sources = ["schema.graphql", "codegen.ts"]
outputs = ["src/generated/"]
run = "npm run codegen"

Running mise prep will install npm and poetry dependencies in parallel, then run prisma and frontend-codegen (also in parallel, since they only depend on npm, not each other).