Grocery store load time cut from 38s to 6.7s, plus multi-store

The challenge

A Canadian online grocery delivery business ran its store on OpenCart. We had set up the store for them in spring 2020, with delivery limited to the areas they served. By late summer the site had become very slow, taking around 38 seconds to load.

At the same time, the business wanted to change its model so customers could shop by individual store, with each store having its own order rules and charges. They needed the existing site fixed and extended rather than replaced.

What we did

• Initial store and delivery-area checks. For the first version we installed the client's chosen theme and built a postal-code serviceability module: an admin-managed list of served areas, a sticky popup asking for the customer's code, and add-to-cart blocked with a request form for areas not yet served. We also added a variant price dropdown, a recent-buyer notification and live chat.
• Clean-up and speed optimisation. We scanned the site, cleaned infected files and optimised performance, bringing load time from about 38 seconds down to 6.7 seconds, and shared the speed reports with the client.
• Store-based shopping. We built multi-store support across the front end and admin: store management, shop-by-store navigation with store logos, minimum and maximum order values, per-store service charges and a store-based XLS product upload.
• Interface updates. We added WhatsApp chat across pages, sped up the homepage banner and updated theme colours, header and logo sizing.
• Migration and support. We moved the site to a new server and domain, set up a business mailbox, and fixed category paging and add-to-cart issues afterwards.

Tech stack

OpenCart 3, PHP, MySQL, cPanel, WhatsApp chat, Zopim chat