What is the sequence tag in module.xml?

The <sequence> tag in Magento 2 defines module dependency and load order. It tells Magento that the current module should be loaded only after the specified module has been loaded.

This is useful when one module depends on configurations, layouts, or functionality from another module.

Why is the sequence tag important?

The sequence tag ensures that Magento loads modules in the correct order during application initialization.

• Prevents dependency conflicts.
• Ensures configuration merging works correctly.
• Allows one module to extend or override another module safely.
• Ensures layout and DI configuration are processed in the correct order.

Where is module.xml located?

The module.xml file is located inside the etc directory of a Magento module.

Typical path:

Example: Using the sequence tag

Suppose a custom module depends on the Magento Catalog module. The module should load only after the Catalog module is initialized.

(File: app/code/VendorName/ModuleName/etc/module.xml)

Example: Multiple module dependencies

A module can depend on multiple modules. In that case, multiple module entries can be added inside the sequence tag.

How Magento uses the sequence tag internally

Magento uses the sequence declaration during configuration merging and module loading.

• Configuration files from dependent modules are loaded first.
• Dependent module configuration overrides are applied afterward.
• Layout updates are processed according to module order.

Important notes about the sequence tag

• The sequence tag only controls module load order.
• It does not automatically install or enable dependent modules.
• The dependent module must already exist in the system.
• It does not affect PHP class loading or dependency injection directly.

Best Practice

Use the sequence tag only when your module depends on another module’s configuration, layout, or functionality.

Avoid unnecessary dependencies because excessive module coupling can make the system harder to maintain and upgrade.