Developers

These guides explain how to extend Formie in your own modules and plugins, including building settings interfaces and connecting custom integrations.

Everything You Need to Know About Formie Schemas

When and why to use Formie schemas — Craft macros analogy, field tab methods, integration form settings, normalisation, and debugging. Helper and node reference lives in UI Schemas.

Adding a Custom Validation Rule

Build a Booking Reference field with matching PHP and JavaScript validation, connect it to a form, and test valid, invalid, and empty values in both paths.