Introwise Payments

Read more about Introwise project here: https://contra.com/p/32ekAWvP-introwise

Implemented payments processing system that supports multiple processors, including Stripe and PayPal.

Features:

First-party integration with Stripe using Connect and PayPal using PayPal for Marketplaces and Platforms

Secure OAuth authentication with no API keys or credentials sharing

Both on-session and async (webhooks) payment flows

Ability to plug in additional payment providers

Direct integration in the product's checkout flow, no redirects