CartServe: a no-code cart drawer merchants design themselves

What CartServe is

CartServe is a cart drawer for Shopify that a merchant designs without code. Drag, drop and style a dozen blocks, add a rewards bar, preview the drawer against any market, and publish. It is the second app under our ServeApps label, and it is on a fully free plan while we grow it: every feature, no caps.

The problem we built it for

The cart drawer is where most Shopify stores leak conversion, and it is also the part of a theme merchants least want to touch. Changing the order of a block, adding a free-shipping bar or a note field meant a theme edit or a developer. We had made those edits for clients enough times to know the drawer should be a product.

What we built

A block builder, live

Line items, a rewards bar, a discount field, a note, upsells, trust badges, a checkout button: each one a block that can be reordered, hidden and styled, with the real drawer updating as the merchant works. Fonts, colours and radii come from the theme by default so the drawer looks like the store from the first second.

Rewards for spending more

A progress bar towards free shipping, a gift or a discount tier, with the copy and the thresholds set by the merchant. The same mechanic we have built by hand for Shopify Plus clients, available to any store.

Built for every market

The drawer is previewed per market, so a German shopper sees German copy and euro prices before the merchant publishes. Shopify Markets handles the translation and currency; CartServe makes it visible in the editor.

How it is built

A theme app extension renders the drawer, so it works on any Online Store 2.0 theme without editing Liquid and is removed cleanly on uninstall. The editor is a Remix app on App Bridge and Polaris. Settings are stored as metafields, which keeps the storefront fast and lets the drawer render without a round trip to our servers.

Why it matters for client work

Building a drawer merchants can run themselves taught us where theme app extensions shine and where they fall short, and that experience goes into every custom cart and checkout we build for Shopify Plus clients.