Creating a Frontend Extension Blueprint

When to use this skill

You're authoring a frontend plugin and want to give other plugins or modules a typed, structured way to contribute UI to it. Think:

• A dashboards plugin that wants modules to register custom dashboard panels
• A code-quality plugin that wants modules to register additional checks shown on a results page
• A reusable "feature flag" plugin where modules contribute UI controls per flag

This is the same pattern Backstage itself uses for PageBlueprint, EntityCardBlueprint, EntityContentBlueprint, FormFieldBlueprint, ApiBlueprint. You're creating a new one of those for your plugin.

Don't create a blueprint when:

• A built-in blueprint already covers the case (use EntityCardBlueprint for catalog-page cards, FormFieldBlueprint for scaffolder fields, etc.)
• Your extension point only fires once and only your plugin will ever populate it — just write a regular extension and skip the blueprint indirection
• You're in a backend plugin — backend uses extension points (createExtensionPoint), not blueprints. See using-backstage-backend-system/references/extension-points.md

What you build