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SubTracker — Subscription & API Cost Tracker

Private tracker for AI subscriptions and API spend

Internal Vailis tool, open-source candidate

Problem

Running an AI-native consulting operation means fifteen-plus subscriptions and as many API keys, spread across Gmail receipts and vendor dashboards. No single place to see what is actually being spent each month or catch forgotten renewals.

Solution

A Chrome extension plus a local FastAPI + SQLite backend. A three-step Gmail pipeline — Discover → Classify → Scan — finds billing domains, then pulls only confirmed receipts. Fuzzy matching on sender names and billing patterns keeps false positives low.

Impact

MVP processing real client data, scoped and signed.

  • Phase 1 shipped: 16 files, ~1,648 lines, 34 passing tests
  • Six real services auto-discovered from Gmail (Claude, Cursor, Google, Gemini, LuxAlgo, MiniMax)
  • False positives reduced from 93 to 28 through pattern filtering
  • 85 candidate domains collapsed to 9 actual billing domains

Stack

Chrome ExtensionReactPythonFastAPISQLite
#personal-tool#automation#gmail-parsing

Client details are anonymised where disclosure was not authorised. Metrics are either directly measured or clearly marked as targets in the project log.

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