Ever wanted to build your own Customer Data Platform (CDP) but felt overwhelmed? You’re not alone. The good news is — it’s totally doable. And you don’t need an army of engineers or a fancy enterprise tool. All you need is Segment, BigQuery and a pinch of know-how.
Let’s take a fun and simple journey into building a lightweight CDP to track, store, and analyze customer data. Ready? Let’s gooo 🚀
What’s a CDP and Why Should You Care?
A Customer Data Platform collects and centralizes customer information. That means you get a 360° view of your users — how they behave, what they love, and where they drop off.
Traditionally, building a CDP was no joke. Big budgets. Complex systems. Tears.
But now, tools like Segment and BigQuery make it easy, fast, and fun. Here’s what we’ll do:
- Use Segment to track user behavior
- Send that data to BigQuery
- Query, visualize and make smart decisions
Step 1: Getting Data In with Segment
Segment is like a magical funnel. It captures data from your website or app and routes it to tools like BigQuery, Google Analytics, or Slack (if you’re into that).
Here’s what Segment does a-maz-ing-ly well:
- Collects clean, structured data
- Requires minimal code
- Works with loads of tools
To get started:
- Create a Segment account
- Add your website or app as a source
- Install the Segment SDK
Let’s say we’re tracking an ecommerce site. Add this simple snippet to your site’s head tag:
<script> !function(){var analytics=window.analytics=window.analytics||[];if(!analytics.initialize) if(analytics.invoked)window.console&&console.error("Segment snippet included twice.");else{ analytics.invoked=!0;analytics.methods=["trackSubmit","trackClick","trackLink","trackForm", "pageview","identify","reset","group","track","ready","alias","debug","page","once","off","on"]; analytics.factory=function(t){return function(){var e=Array.prototype.slice.call(arguments); e.unshift(t);analytics.push(e);return analytics}};for(var t=0;t<analytics.methods.length;t++){ var e=analytics.methods[t];analytics[e]=analytics.factory(e)}analytics.load=function(t){ var e=document.createElement("script");e.type="text/javascript";e.async=!0; e.src="https://cdn.segment.com/analytics.js/v1/" + t + "/analytics.min.js"; var n=document.getElementsByTagName("script")[0];n.parentNode.insertBefore(e,n)}; analytics.SNIPPET_VERSION="4.1.0"; analytics.load("YOUR_WRITE_KEY"); analytics.page(); }}(); </script>
Replace YOUR_WRITE_KEY with the one from your Segment dashboard. Boom. You’re tracking page views!
Want to track user sign-ups too?
analytics.track('Signed Up', { plan: 'Pro', source: 'Landing Page' });

Every time a user signs up, Segment sends this data to its pipeline. Next stop: BigQuery!
Step 2: Send Data to BigQuery
Head to your Segment dashboard and discover the power of Destinations. Add BigQuery as a destination and configure it with your Google Cloud project.
Here’s what you’ll need:
- A Google Cloud Platform account
- A BigQuery dataset
- Service account key in JSON format
Segment will ask for this info and handle the rest. Channels are open: your event data starts flowing into BigQuery in real-time ⚡
You’ll see tables like:
- pages: page visits
- tracks: events like sign-ups, purchases
- identifies: user identification and traits

Step 3: Making Magic with SQL
Now the fun begins. You have a mountain of data at your fingertips. Let’s dig into it with some simple SQL queries.
Want to know how many sign-ups happened by day?
SELECT DATE(event_timestamp) AS signup_date, COUNT(*) AS total_signups FROM `your_project.your_dataset.tracks` WHERE name = 'Signed Up' GROUP BY signup_date ORDER BY signup_date;
Or how about checking which plan is most popular?
SELECT properties.plan AS plan_type, COUNT(*) AS total FROM `your_project.your_dataset.tracks` WHERE name = 'Signed Up' GROUP BY plan_type ORDER BY total DESC;
BigQuery’s SQL is lightning-fast, even for huge datasets. Perfect for when your startup becomes Internet-famous. 🌟
Step 4: Turn Data into Beautiful Dashboards
You’ve got the data. You’ve got the insights. Now, make it pretty.
The easiest way? Connect BigQuery to Looker Studio (formerly Data Studio).
With just a few clicks you can:
- Visualize user trends
- Track marketing performance
- Share dashboards with your team
Don’t like charts? Export a CSV. Build a Slack alert. Send an email. It’s your data. Party with it 🎉
Tips to Keep It Smooth
Okay, you’ve got this CDP rolling. Here are a few pro tips to keep it stress-free:
- Name events consistently: “Signed Up” is not the same as “Signup”.
- Track context: Add device type, source, campaign info — the more context, the better.
- Use userId wisely: Identify users after login or signup to connect anonymous and known interactions.
- Set up transformation: Use dbt or SQL views to clean and model your data.

A Lightweight Powerhouse
With just two tools — Segment and BigQuery — you’ve built something powerful. You’re capturing customer interactions. You’re organizing it in a database built for speed and scale. You’re extracting insights that fuel smarter decisions.
And it didn’t take 12 months or a team of 20 people. It took you, a little time, and a willingness to learn.
Give yourself a high five 🙌
What’s Next?
Want to go further? Here are some fun directions:
- Add reverse ETL to feed data back to CRM or email tools
- Build LTV and churn prediction models
- Use dbt for smarter transformations
- Set up automations with Airflow, Zapier or Retool
The sky’s the limit. Your lightweight CDP is only the beginning. 🚀
Happy tracking!