GUN - Self-hosted Firebase.

OneSignal - Customer engagement platform used by over 1 million developers and marketers; the fastest and most reliable way to send mobile and web push notifications, in-app messages, emails, and SMS.

Firebase - Firebase is a cloud service designed to power real-time, collaborative applications for mobile and web.

SignalR - SignalR is a server-side software system designed for writing scalable Internet applications, notably web servers.

ScreenshotMAX - The all-in-one Screenshot API for developers: capture websites, generate PDFs, record videos, and automate it all with powerful, scalable infrastructure. No browser setup, no hassle. Just clean results, fast.

Supabase - An open source Firebase alternative