Payment
Integrations

LONG-TERM ENGINEERING PARTNERSHIPS

Payment flows look simple when they work.

The complexity behind every payment

Behind one successful payment there is usually a lot going on. Provider integrations, transaction states, authentication, failed payments, refunds, limits, reporting, reconciliation and edge cases that users should never need to think about.

That is where we usually help.

We build payment flows, wallet features, checkout experiences and transaction systems for fintech products, digital platforms and regulated environments.

The goal is not to make payments look complicated. The goal is to make them feel boring in a good way. The user pays, the system knows what happened, and the business can trust the result.

What we can help with

Payment Provider Integrations

Digital Wallet Experiences

Transaction Flow Development

Payment API Integrations

Secure Checkout Experiences

Fiat & Digital Asset Payment Systems

Multi-Platform Payment Applications

Identity & Authentication for Transactions

Payment Workflow Automation

How we work

We usually work close to product, backend, compliance and security teams.

That matters, because payment work touches many parts of the product. User experience, backend logic, risk rules, transaction data, provider APIs, support flows and sometimes regulatory checks.

If these things are designed separately, problems usually show up later, when they are more expensive to fix.

Technology we usually work around

Payment provider APIs

Wallet infrastructure

Mobile and web applications

Secure API integrations

Event driven transaction systems

Authentication and authorisation

Backend and enterprise integrations

Transaction monitoring and reporting

Security & reliability

Payments need to be secure, but they also need to be clear.

A failed payment, duplicate transaction or unclear payment state can quickly become a support problem, a trust problem or a business problem.

That is why we pay attention to access, authentication, transaction status, error handling, audit trails and how the system behaves when something does not go as planned.

Relevant experience

01

Our teams have worked on digital wallet and payment related platforms, including systems that support buying and selling BTC, ETH and other digital assets.

02

We have also delivered payment integrations and transaction flows across mobile and web products for fintech and digital product clients.

EQUALEYES

A digital wallet built for secure transactions

RockWallet brings account setup, buying, selling, swapping, sending and receiving assets into one wallet. These journeys had to remain easy to follow while meeting the security and regulatory requirements behind them.



We brought identity verification, biometric authentication, external verification services and transaction monitoring into the wallet, helping users complete the necessary checks without unnecessary friction. 



For users, the experience stayed clear. Behind the scenes, the platform could apply stronger controls around access, transactions and advanced wallet features.

KYC / AML

Secure onboarding and verification flows

90 sec

Quick wallet setup

EQUALEYES

Sparkasse: Preparing mobile banking for Apple Pay

Sparkasse needed to modernise the mobile foundation of D-Mobile without disrupting the experience its existing cardholders already trusted. We rebuilt the native iOS application from the ground up, preserving established user journeys and backend integrations while re-architecting the app around Apple Pay card provisioning.



Behind a deliberately familiar interface, the work reached deep into the payment stack: card systems, authentication, device binding, security rules, provisioning flows and the underlying payment infrastructure. Cardholders can bring their cards into Apple Wallet through all three provisioning paths: manual entry, in-app "Add to Apple Wallet", and provisioning to paired devices, and pay directly from Apple Watch, with the same security guarantees enforced end to end.

The result is a payment experience that feels effortless to the user and is engineered to bank-grade standards underneath.

EQUALEYES

Mobile-first ecommerce for personal care

Selling personal care products through one-time purchases, subscriptions and bundles requires more than a standard online shop.



We built a multilingual, mobile-first shopping experience with payment flows adapted to the UK and Turkish markets.



Customers can buy products, manage subscriptions and adjust deliveries in one place, while the platform supports recurring orders and day-to-day ecommerce operations behind the scenes.

+270%

Growth in new customer acquisition in 2025

94%

Unique paying customers

EQUALEYES

OTP: Digital banking beyond the migration

During a core system upgrade and bank merger, OTP had to keep mobile and web banking reliable for real customers while the systems behind it were changing.

Our team helped build and launch the new mobile and web platforms, including the design system, digital onboarding, Apple Pay and Google Pay integrations that brought everyday payments into the wider banking experience.



Since then, we have continued to evolve the platforms with accessibility improvements, stronger authentication and changes that make everyday banking more efficient for customers and the bank.

4x

Best-rated Slovenian mobile banking app
 across iOS & Android

577K+

Mobile app installations

Let’s talk about your next platform

Whether you are modernising a banking platform, improving an internal workflow, building a customer portal or trying to connect systems that do not work well together, we can help.

CONTACT US

Engineering teams for banks, telecoms, insurance companies and regulated digital platforms.

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