Digital Analytics Suite

A portfolio of custom-built digital analytics tools demonstrating proficiency in JavaScript development, analytics instrumentation, session replay, experimentation, and tag management — the core competencies of modern digital experience platforms.

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Google Analytics 4 Integration

Live on this site

Full GA4 implementation with a custom JavaScript analytics wrapper that provides typed event tracking. Custom events include article reads with scroll depth, music plays, resume downloads, navigation clicks, and outbound link tracking. Custom dimensions track content lens types and user roles.

GA4 gtag.js Custom Events Custom Dimensions Scroll Tracking

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Session Replay Engine

Custom-built · Quantum Metric / Tealeaf pattern

A lightweight JavaScript session recording library built from scratch. Captures DOM mutations, click coordinates, scroll positions, form interactions (privacy-safe — no input values), JavaScript errors, network request timing, and page visibility changes. Event batches are flushed to a SQLite-backed API every 10 seconds. An admin replay viewer reconstructs sessions with a timeline scrubber and event inspector.

Session Recording MutationObserver XPath Tracking Privacy-Safe SQLite Storage sendBeacon API

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A/B Testing Engine

Custom-built · Optimizely / Adobe Target pattern

A client-side A/B testing framework that handles experiment assignment, DOM modification, and conversion tracking. Uses deterministic hashing for stable user-to-variant mapping, cookie-based persistence, and configurable traffic allocation. Supports text, HTML, style, and class modifications via CSS selectors. Conversion events pipe through GA4 for unified reporting. Experiment configs are managed via admin API.

A/B Testing Deterministic Hashing DOM Modification Conversion Tracking GA4 Integration

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Analytics Dashboard

Admin panel integration

Custom analytics dashboard built into the admin panel showing session metrics, page performance, device breakdown, referrer sources, error tracking, and experiment results — all visualized with Chart.js. Aggregates data from the session replay engine and provides a unified view of site performance.

Chart.js Data Visualization SQLite Aggregation Error Monitoring

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Tag Auditing Tool

Bookmarklet · Run on any page

A JavaScript diagnostic tool that audits any webpage for analytics tags, data layers, and tracking pixels. Detects GA4, Adobe Analytics, Adobe Target, Optimizely, Facebook Pixel, GTM, Segment, Hotjar, PostHog, Quantum Metric, Tealeaf, Mixpanel, and Amplitude. Reports tag firing sequence, data layer contents, and network requests to analytics endpoints. Available as a bookmarklet for use on any site.

Drag this to your bookmarks bar:

Tag Auditor

Tag Detection Data Layer Performance API Bookmarklet

Live Audit: This Page

Click to run the tag auditor on this page and see what analytics tags are detected.

Architecture

┌─────────────────────────────────────────────────┐
│                   Browser                        │
│  ┌──────────┐  ┌──────────┐  ┌───────────────┐  │
│  │ GA4 gtag │  │ Session  │  │ A/B Testing   │  │
│  │ wrapper  │  │ Replay   │  │ Engine        │  │
│  └────┬─────┘  └────┬─────┘  └──────┬────────┘  │
│       │              │               │           │
│       ▼              ▼               ▼           │
│  Google Analytics  /api/analytics  /api/analytics │
│  4 Servers         /sessions       /experiments   │
└─────────────────────┬──────────────┬─────────────┘
                      │              │
                      ▼              ▼
              ┌──────────────────────────┐
              │    SQLite (auth.db)      │
              │  ┌────────────────────┐  │
              │  │ replay_sessions    │  │
              │  │ replay_events      │  │
              │  │ experiments        │  │
              │  │ experiment_events  │  │
              │  └────────────────────┘  │
              └──────────────────────────┘
                      │
                      ▼
              ┌──────────────────────────┐
              │  Admin Dashboard         │
              │  ┌──────────────────┐    │
              │  │ Analytics Tab    │    │
              │  │  - Sessions      │    │
              │  │  - Pages         │    │
              │  │  - Devices       │    │
              │  │  - Errors        │    │
              │  │  - Experiments   │    │
              │  │  - Session Replay│    │
              │  └──────────────────┘    │
              └──────────────────────────┘