The Complete Guide to eCommerce Development 2024

Superior Bands on Superior Speed

WatchStyle is a well known supplier of high-end replacement watch bands around the globe. Offering a wide range of valuable, exotic leather watch bands WatchStyle cares of their customers’ wealth and prestigious status and very popular in the world of luxury.

  • 10 000 items in stock
  • Shipping to 96 countries
  • 10+ years in business


To maintain high quality customers service online the owners made a decision to switch store performance speed to the next gear.
Speed up mobile upload
Increase desktop load speed

Analytics and Solution

To locate performance issues, we performed a complex analysis of the store, including both server and CS⁠-⁠Cart speed optimization analysis.
Eliminate code blockage
Speed up server response
Compress HTML
Optimize images size

Implementing the Project

Eliminate render-blocking JavaScript and CSS in above-the-fold content

We found out that the client modified the code to block automatic script displacement down the page. This modification decreased page loading time. We brought the code back to original view.

Development of additional functionality and integration with third-party services

Overwhelming amount of sessions in

Redis is an in-memory data structure store, used as a database, cache and message broker. Every website visitor creates a session which is being stored in Redis around a month. The store periodically extracts all sessions from Redis and replaces the old ones with new. There were 75 355 sessions in WatchBand storage at the moment we started the project. Due to sessions amount extracting was very slow and caused around two seconds response delay.

Commented out code in “clear” function

This function serves to clear Redis cache. It triggers every time the database changes. It happens very often (log change, order placed, adding to cart). After clearing up the cache builds up back. Commented out code on WatchBands was slowing down this process.
We reviewed the code and fixed it.

«Minify HTML» CS-Cart Add-on installed

This is a free add-on that makes HTML more compact by removing unnecessary white spaces, line breaks, tabs and other extra objects. It makes websites load faster, reduces mobile transfer costs and optimizes storage on embedded systems.

Images optimization

To speed up images upload we re-saved them with more compact .jpeg compression.
Smaller image sizes means faster page loads, faster backups, less bandwidth usage and happy customers.


The web store became around 58% faster on mobile and around 34% on Desktop as Google PageSpeed indicated.
+58% suggestions summary on mobile Google PageSpeed
+34% suggestions summary on desktop Google PageSpeed
12 working hours
Launched the project within 7 working days

Google PageSpeed changes

To speed up images upload we re-saved them with more compact .jpeg compression.

It was my pleasure working with Simtech. I felt the answers were professional and competent. The deadlines and the quality met all my expectations.

Michael Kares, CEO of WatchStyle