Composer scripts execute commands with the installing user's permissions, so script definitions and plugins must be reviewed before running them.
What It Does
Keep scripts simple, documented, and limited to reviewed commands. Validate package metadata and build optimized autoload maps. Disable arbitrary package script execution when inspecting untrusted projects.
Requirements and Compatibility
Use a supported PHP runtime and install any third-party tool or extension explicitly shown in the examples. Commands should be run from the project root unless stated otherwise.
Syntax, Inputs and Results
The examples separate configuration, the smallest working operation and a realistic follow-up task. Adapt file paths and dependency versions to your own project.
Example 1: Basic Use
Keep scripts simple, documented, and limited to reviewed commands.
{
"scripts": {"lint": "@php -l src/bootstrap.php", "check": "@lint"},
"scripts-descriptions": {"check": "Run reviewed local checks"}
}
Example 2: Another Case
Validate package metadata and build optimized autoload maps. Disable arbitrary package script execution when inspecting untrusted projects.
composer validate --strict
composer dump-autoload -o
composer install --no-scripts
Practical Example
Install the exact locked versions and verify the target PHP runtime. Disable arbitrary package script execution when inspecting untrusted projects.
composer install --no-interaction --prefer-dist
composer check-platform-reqs
composer install --no-scripts
For production, apply the compatibility and edge-case limits described below.
Important Behavior and Edge Cases
Use the checked-in lock file for reproducible application builds.
Comparison with Related Functions and Tools
| Subject | Key difference |
|---|---|
| composer install vs composer update | install follows composer.lock; update resolves new versions and updates the lock file. |
Common Beginner Mistakes
| Mistake | Correct approach |
|---|---|
| Treating a version range as a fixed installed version | Commit composer.lock for applications and run composer install in deployment. |
| Skipping the prerequisite of this specific workflow | Install or configure the named tool and confirm the example can actually run. |
| Ignoring edge conditions | Use the checked-in lock file for reproducible application builds. |
Key Takeaways
- Composer scripts execute commands with the installing user's permissions, so script definitions and plugins must be reviewed before running them.
- Use the checked-in lock file for reproducible application builds.
- Keep application configuration, source code and validation tests under version control.
Use these examples as a starting point, then validate the result with the actual PHP build, dependencies and inputs used by your application.