When Flooid, a leading unified retail commerce platform provider, rolled out a new loyalty (Clubcard) for One Stop, they needed one thing to be certain:
No matter how busy the stores got, the tills couldn’t slow down.
Owned by Tesco, One Stop operates over a thousand convenience stores across the UK, so even a small delay at the till can quickly turn into long queues, frustrated customers, and lost revenue. Our job was to make sure that didn’t happen.
The Challenge
Flooid had integrated a loyalty solution (Tesco Clubcard) into One Stop’s POS and Self-checkout systems. That meant every eligible transaction now needed to:
- Look up the loyalty account
- Apply any offers or discounts
- Record the transaction for points and reporting
All in real time, while customers were standing at the till.
The performance target was clear:
- Support high volumes of transactions across a large estate
- Stay stable during peak trading periods (think Christmas rush, seasonal promotions, and weekend spikes)
- Avoid any noticeable slowdown in the checkout experience
What We Did
We were brought in to design and run volume and performance testing for the loyalty integration.
Here’s how we approached it:
- Modelled real-world peaks
We built test scenarios that mimicked true store behaviour: busy periods, back-to-back transactions, loyalty and non-loyalty customers, and different basket sizes.
- Designed robust load tests
We gradually increased the load to simulate sustained high checkout activity, then pushed beyond typical peak levels to understand how the system behaved under extreme pressure.
- Monitored end-to-end performance
We tracked response times across the entire flow – POS, Self checkout, middleware, and loyalty services to pinpoint any bottlenecks, not just prove the average looked okay.
- Collaborated on tuning and fixes
Working closely with the engineering team, we used the test results to guide optimization, capacity adjustments, and code-level improvements where needed.
- Validated against peak scenarios
Finally, we re-ran the tests after tuning to confirm the system was ready for real-world peaks, not just lab conditions.
The Outcome
By the end of the engagement:
- The POS and loyalty integration could reliably process high transaction volumes under sustained load.
- The solution remained stable and responsive during simulated peak trading periods.
- Flooid and One Stop gained confidence that the new Tesco Clubcard integration wouldn’t be the reason queues built up in stores.
In short, customers still get through the checkout quickly, they just earn more rewards while they do it. Integrating Tesco Clubcard into One Stop stores’ POS offers Tesco a range of benefits including increased loyalty, deeper customer insights, and broader reach for its market-leading rewards programme.