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I Was Tired of Sending My Users' Data to Google — So I Built My Own Analytics

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I'm a final year CS student. I build things in production.

Last year, I was working on [Ucoder](https://www.ucoder.in) — a full-stack platform I've been building since college. At some point I needed analytics. I wanted to know: are people actually using this? Which features are being used? Where are errors happening?

So I did what everyone does. I installed Google Analytics.

It worked. But something felt wrong.

The Problem

GA4 sends every user interaction to Google's servers. Every click, every session, every user's IP and device — all of it leaves your infrastructure and goes somewhere you don't control.

For a platform where I cared about user trust, that felt like a betrayal.

So I looked at alternatives:

  • Plausible — privacy-first, cookie-free, clean dashboard. But it only gives you pageviews, referrers, and bounce rate. No custom events, no error tracking, no real product analytics.
  • Mixpanel — powerful, but $28/month per 10K users. At scale, brutal. And the setup takes half a day just for event taxonomy.
  • Microsoft Clarity — session replays and heatmaps only. No event tracking.
  • Self-hosted Matomo — closer, but heavy to maintain and the UI feels dated.

None of them did what I actually needed:

Track real user behavior, capture errors, support custom events — without cookies, without sending data to a third party, and without a painful setup.

So I built it myself.

Introducing Ucoder Insights

Ucoder Insights is a privacy-first, cookie-free analytics platform with its own npm SDK.

It tracks:

  • 📄 Page views (SPA-aware, works with Next.js, React, Vue)
  • ⚡ Custom events
  • 🔴 JavaScript errors (with stack traces)
  • 📊 Core Web Vitals (LCP, FID, CLS)
  • 🌐 Referrers, UTM params, device/browser info

All without cookies. All processed on your own terms.

How It Works — Technical Overview

The SDK 

npm install ucoder-insight
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import { initUcoderInsight } from 'ucoder-insight';

initUcoderInsight("projectid"{
  // Your optional settings here
});
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That's it. One function call. No configuration overhead.

The SDK is ~9.5KB gzipped. It uses a beacon API to send events so it never blocks the main thread. For SPAs, it listens to history.pushState and popstate to track client-side navigation automatically.

The Backend Architecture

The backend is built with Express 5 + TypeScript. When an event comes in:

  1. Request hits the Express API
  2. Passes through express-validator for input sanitisation
  3. Gets pushed into a BullMQ job queue backed by Redis
  4. A background worker processes the queue and writes to MongoDB

Why a queue? Because analytics should never slow down your app. If the ingestion endpoint is under load, events queue up and get processed asynchronously — your tracked application is never affected.

Client SDK
   │
   ▼
Express API  ──→  BullMQ Queue (Redis)
                       │
                       ▼
                  Worker Process
                       │
                       ▼
                   MongoDB
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Privacy by Design

  • No cookies — identification uses a daily-rotated hash of IP + User-Agent. No persistent tracking across days.
  • No PII storage — we never store IPs or personal data.
  • Your data stays yours — events go to your project only, not a shared Google/Meta data warehouse.

What This Solves That Others Don't

1. Error Tracking + Analytics in One Place

With GA4 or Plausible, you need a separate tool (Sentry, LogRocket) for error tracking. With Ucoder Insights, JavaScript errors are captured automatically — with the page URL, user agent, and stack trace — right alongside your pageview and event data.

No context switching between dashboards.

2. Real Custom Events, Simply 

import { trackEvent } from 'ucoder-insight';

// Track anything
trackEvent('signup_completed', { plan: 'free', method: 'email' });
trackEvent('feature_used', { feature: 'export_csv' });
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Plausible's custom events require manual script tagging. Mixpanel requires you to plan an entire event taxonomy before you start. Here, you call one function.

3. SPA-First

Most analytics tools were built for traditional multi-page websites. Ucoder Insights was built with SPAs in mind from day one — it handles pushState navigation, React Router, Next.js App Router, and hash-based routing out of the box.

The Stack

Layer Technology
SDK TypeScript, Beacon API
Frontend Dashboard Next.js 16, React 19, Tailwind CSS 4
Backend Express 5, TypeScript, Socket.IO
Queue BullMQ + Redis (ioredis)
Database MongoDB (Mongoose 9)
Deployment Docker + PM2 on Linux VPS

Current Status

The platform is live at insights.ucoder.in and running in production on Ucoder.in.

The npm package ucoder-insight is public at v1.1.3.

I'm a solo developer and this is a real project — not a side project I'll abandon. I use it myself, which means I have a real incentive to keep it working and improving.

What's Coming Next

  • Alert system — get notified on Slack/email when error rate spikes or traffic drops
  • Server-side proxy — bypass ad-blockers without compromising privacy
  • Funnel analysis — visualise conversion paths across custom events
  • API access — pull your analytics data into your own dashboards

Try It 

npm install ucoder-insight
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If you're building something and tired of sending your users' data to Google — give it a try. And if you have feedback, I genuinely want to hear it.

Built by Soumyadip Maity — Full Stack Developer, final year CS student, West Bengal, India.

Source: dev.to

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