Senior Backend Engineer (Mobile Monetization) | Feeld in Katowice

GT was founded in 2019 by a former Apple, Nest, and Google executive.

GT’s mission is to connect the world’s best talent with product careers offered by high-growth companies in the UK, USA, Canada, Germany, and the Netherlands. On behalf of

Feeld , GT is looking for

a Senior Backend Engineer

to help them improve their inclusive dating application. About the Client

Founded in 2014 as a dating app,

Feeld

gathered millions of users in one place to create a safer and more inclusive space online for everyone open to experiencing people and relationships in a new way. Their mission is to elevate the human experience of sexuality and relationships and create a world where everyone is more intimately connected to each other and themselves. The technology stack of the project:

Node.js, NestJS, GraphQL/REST, TypeScript, AWS, DynamoDB, PostgreSQL, SQS, EventBridge, WebSockets. About the Role

We are looking for a

Senior Backend Engineer (Mobile Monetisation)

to take ownership of the backend systems powering Feeld's subscription and in-app purchase experiences across iOS and Android. The ideal candidate brings

strong hands-on experience with mobile monetisation platforms such as Adapty, RevenueCat, or similar solutions , as well as integrating mobile payment flows with custom backend services. This includes managing subscription lifecycles, synchronising payment data, handling receipts, and ensuring accurate entitlement management. We're looking for a

highly experienced, proactive engineer with the potential to act as a technical lead , capable of independently driving complex technical initiatives, contributing to architectural decisions, and ensuring the reliability and scalability of revenue-critical systems. Full-time, long-term Preferred immediate start Responsibilities:

Take ownership of the backend systems supporting Feeld’s monetisation, ensuring their reliability, performance, and contribution to business goals.

Design, develop, and maintain scalable backend services and integrations for subscriptions, billing, payment processing, entitlements, pricing, and promotional features.

Ensure the accuracy, stability, and reliability of monetisation flows, proactively identifying and resolving production issues that could impact revenue or user experience.

Support the development and optimisation of subscription and payment flows, including improvements to system performance, scalability, and error handling.

Implement and maintain feature flags, testing, and analytics instrumentation to support experimentation and continuous improvement of monetisation features.

Collaborate with Product, Engineering, and Data teams to build and improve analytics and reporting capabilities, providing insights into revenue performance, user behaviour, and system health.

Essential knowledge, skills & experience:

5+ years of commercial backend development experience , ideally building high-load, business-critical systems.

Proven experience with mobile monetisation and subscription platforms , such as Adapty, RevenueCat, or comparable solutions.

Hands-on experience implementing mobile in-app purchases and subscription flows

for iOS and/or Android applications, beyond web-based payment integrations.

Experience integrating mobile payment platforms with custom backend systems , including payment data synchronisation, receipt handling, subscription status tracking, and entitlement management.

Strong understanding of

mobile subscription and payment lifecycles , including renewals, cancellations, refunds, failed payments, and subscription state changes.

Experience ensuring the

accuracy, reliability, and consistency of revenue-critical backend systems , including troubleshooting production issues.

Strong backend development experience with

Node.js or TypeScript or JavaScript , ideally using NestJS and building GraphQL or REST APIs.

Good understanding of

event-driven architectures, asynchronous processing, and distributed systems .

Experience writing reliable

unit and integration tests .

Strong technical ownership, independent problem-solving, and architectural decision-making skills, with the

potential to take on technical leadership responsibilities .

Strong communication skills and

full professional proficiency in English.

Nice to Have

Experience with

AWS cloud infrastructure , SQL and NoSQL databases. Our current stack includes ECS, DynamoDB, SQS, EventBridge, and PostgreSQL.

Experience working directly with

Apple App Store and Google Play billing ecosystems .

Experience running

monetisation experiments , including A/B testing, subscription pricing changes, and conversion optimisation.

Experience managing

regional pricing, multiple currencies, and country-specific monetisation strategies .

Experience analysing the performance of monetisation experiments, including revenue, subscription conversion, and retention metrics.

Previous experience acting as a

Tech Lead or Lead Backend Engineer , mentoring engineers, and driving technical decisions.

Interview Steps

GT interview with Recruiter

GT technical interview

Client technical interview

Final interview

Reference Check

Offer