Ecommerce & Retail · Commerce operations
A custom Shopify application to manage inventory reservations and enforce purchase limits for limited-edition product releases.
Outcome
Limited drops sell without oversells: thousands of concurrent cart holds and purchase limits enforced outside Shopify, which cannot reserve stock itself.
The client operates a direct-to-consumer business founded on scarcity. They manufacture and sell collectible tags from retired aircraft, serving a dedicated community of enthusiasts who value the unique history and limited availability of each piece. Their business model depends on maintaining the integrity of these limited-edition product drops.
The success of their model created a new challenge. High-demand releases were selling out in seconds, often to a small number of buyers who would purchase the entire stock. This left the majority of their customer base frustrated, undermining the community feel the brand had carefully built. The standard Shopify platform did not offer the controls needed to ensure a fair distribution during these critical sales events.
We were brought in to design and build a custom system that integrates with their Shopify store. The solution introduces a layer of control over their inventory, implementing timed cart reservations and purchase limits. This ensures that more customers have a reasonable opportunity to purchase, protecting the brand's relationship with its community.
The challenge
How we solved it
Technologies
When a customer adds a high-demand item to their cart, our system temporarily reserves that unit of stock for a merchant-defined period. A visible countdown timer lets the customer know how long they have to complete their purchase. This prevents cart sniping and creates an orderly, predictable buying experience during a competitive product drop.
Through a custom interface within the Shopify Admin, the client can set a maximum purchase quantity for any individual product. This rule is enforced at the cart level, preventing any single buyer from acquiring more than their share. It ensures wider product distribution, reinforcing the collectible nature of the items and the fairness of the brand.
How we built it
Moved the reservation state out of Shopify entirely, because the platform has no concept of a temporary hold. Shopify inventory is either available or sold. A timed cart hold with a purchase limit is stateful, needs timers ticking for thousands of carts at once, and cannot live in a theme. So an external Laravel service on its own cloud server became the source of truth for reservations and talks to the Shopify API to enforce them. The storefront side is a small JavaScript layer that injects the countdown into the cart and shows quantity limits on product pages, and a Polaris app gives the merchant the rules. The drop still runs on Shopify; the fairness logic runs beside it.
In the client's words
“Shopify cannot hold stock. This does. Our drops stopped overselling.”
Tell us what you're building. We'll show you how we'd approach it and what it would take to ship.