Track Subscriptions Without Bank Access

The Nex Sub Tracker is a production-ready Chrome Extension (Manifest V3) designed for developers who want to ship a functional financial utility or use a robust template for their own browser tools. It solves the privacy hurdle of subscription tracking by monitoring domain visits locally rather than requiring sensitive bank API integrations.

What it does

This skill provides a complete, "no-build" extension source using a vanilla JS, HTML, and CSS architecture. Key features include:

• Smart Domain Monitoring: Automatically detects visits to subscription services and badges the toolbar with monthly costs.
• Adaptive Learning: Suggests tracking new services after repeated visits to untracked provider domains.
• Spend Dashboard: A popup UI featuring total monthly spend, category breakdowns, and renewal reminders.
• Inactivity Logic: Flags subscriptions that haven't been "used" (visited) in 30+ days to help users cut costs.

Why use this skill

Instead of prompting an AI to write a scaffold that might contain API hallucinations or outdated MV3 syntax, this skill delivers a fully tested, shipped product. It skips the complexity of modern build chains (no Webpack, no NPM) in favor of a fast reload-and-test developer loop. You get a logic-heavy background service worker, storage management, and a pre-populated provider database (services.json) out of the box.

Supported Patterns & Tools

• Manifest V3: Modern Chrome extension standards.
• No-Build Architecture: Pure Vanilla JS, CSS, and HTML.
• Chrome APIs: Alarms, Storage, Notifications, and Tabs.