👩‍💻Devs! How does everyone here typically connect their landing page, pricing page and app?

Typically when setting up a SaaS project I'll have my marketing pages live at https://www.mysaasapp.com and my application live at https://app.mysaasapp.com. The glue between them is the pricing page. The UI lives on the marketing site but clicking pricing Option A will take you to the onboarding flow at https://app.mysaasapp.com/signup.... I'm curious how everyone else here does this? Is there a better easier way?