Payment and Subscription Systems

Client:

Castro Capital

Service:

Brand Strategy

Date

June 28, 2026

Checkout, payments, and recurring billing that keep working without manual effort.

We build the systems that get you paid: checkout, payments, and subscription billing that keep working without manual effort. Taking money is the part of your product that has to be right every time, and we build it to be reliable, secure, and easy to run.

Get paid reliably, and keep subscriptions from leaking

The payment layer is where a product cannot afford to be sloppy. We build checkout and payment processing that customers trust, connected to the payment providers you already use. Money comes in cleanly, and every transaction is recorded, receipted, and easy to reconcile.

Subscriptions leak revenue when nobody is watching the edges: a failed card that never retries, an upgrade that does not prorate, a renewal that silently fails. We build billing that handles plans, upgrades, downgrades, renewals, and failed payments, so recurring revenue keeps flowing and a billing problem does not turn into a support fire or a lost customer.

We handle payments through trusted payment providers and keep sensitive data where it belongs, so you get security without taking on risk you do not need to. Refunds, invoices, and receipts all work the way your customers and your finance team expect.

We build with our own engineers in the United States. You choose how we work: we can own the payment system end to end, or work alongside your project manager and fit into your process. One codebase can serve your web app, iOS app, and Android app at once, so customers pay the same way everywhere, and after launch we can keep the system monitored and supported.

See how we build: EVDC

EVDC is a good example. It handles payment for charging sessions across a web app, an iOS app, and an Android app, all from a single codebase maintained by one team. Getting payment right on every platform, every time, is the kind of work this service is built for.