Website Push Notification Integration

I want to add real-time push notifications to my website so visitors on both iOS and Android receive timely alerts even when the browser is closed. The core work is to set up and integrate a reliable web-push service—whether that’s Firebase Cloud Messaging, OneSignal, or a comparable solution—then wire it up to my existing codebase.

Here’s what I’m expecting:
• A fully configured push-notification service and service-worker script
• Subscription opt-in implemented on the site (with clear permission prompts)
• An easy way for me to send test and production messages
• Cross-browser testing on Chrome, Safari, Edge, and Firefox for both mobile platforms
• Brief hand-off notes so I can manage keys, tokens, and future campaigns myself

If you’ve previously shipped web push at scale or have deep knowledge of the browser Push API, that’s exactly the expertise I’m after.