Ruslan Leteyski quit a UI/UX design job in 2017 to run Shopify dropshipping stores, but found that market too crowded to win in. Reasoning that it pays to sell shovels during a gold rush, he taught himself to code and shipped Upsell X, a small pre-checkout upsell app that pulled in a few hundred merchants and a thousand or two dollars a month. That first taste of product revenue gave him the confidence and the merchant base to try something bigger.

Checkout X started by accident. While trying to launch an online pharmacy that no Shopify-approved payment provider would touch, Ruslan built a way to bypass Shopify's checkout and plug in any payment processor. The pharmacy went nowhere, but the workaround was the real discovery. The first real customer arrived through an Upsell X support ticket: a French dropshipping operation asked for a one-page checkout with post-purchase upsells. Ruslan quoted them roughly €5k a month and asked them to prepay, which they did over PayPal. That single prepayment validated the idea and funded full-time work on it.

The first launch was a mess. The checkout itself worked, but everything that depended on Shopify's native checkout broke at once: ad pixels, abandoned cart emails, refunds, SMS flows. Ruslan spent an entire summer rebuilding or re-integrating each piece before the app went live for real in September 2018. From there, growth came from two channels he never paid to seed. Competitors of his customers kept noticing the unusual custom checkouts, dug into the page source where Ruslan had deliberately left marketing breadcrumbs, and signed up themselves. An affiliate program that paid 15 to 25 percent of revenue forever drove around 40 percent of customers, and it worked because the affiliates were real users who liked the product.

Over the next few years Checkout X reached about 6,000 active merchants at roughly €100 each per month, peaking at a self-reported €600k in monthly recurring revenue. The team never grew past 16 people, all remote, and the product never listed on the Shopify App Store or ran a single paid ad. The catch was always structural: control over checkout is central to Shopify's own business, and Ruslan knew he was piggybacking on a platform that would eventually object. In 2023 Shopify moved against alternative checkout apps, Checkout X was wound down, and Ruslan laid off the team and moved on to new products, later building Vanga AI and Zipchat.