Staff Software Engineer

WHO WE ARE

At Trustly, we're building a smarter, faster, and more secure financial future by revolutionizing the world of payments. As a global leader in Open Banking Payments, we are establishing Pay by Bank as the new standard at checkout, providing unparalleled freedom, speed, and ease to millions of consumers and merchants worldwide.

Our Ambition: To build the world's most disruptive payment network and redefine what the payment experience should feel like.

Trustly is a global team of innovators, collaborators, and doers.  If you are driven by a strong sense of purpose and thrive in a dynamic, entrepreneurial, and high-growth environment, join us and be part of a team that's transforming the way the world pays.

About the role

As Trustly's Staff Engineer for our next-generation consumer product (GoConsumer), you will own the technical direction of an AI-powered, gamified financial experience designed to help everyday earners build healthier financial habits. 

You will partner with a Product Manager and a Product Designer to evolve the MVP (built by an external venture builder) into a high-quality, scalable, secure application.

Over time, you will help build and lead an engineering team under you. Your responsibility spans architecture, AI integration, safety, compliance, data flows, reliability, and shipping high-quality features fast.

You'll closely collaborate with:

- The AI-focused Product Manager 

- The UX/Gamification Designer 

- Venture build team delivering the initial MVP through to PMF (Product Market Fit)

- Data scientists, ML engineers, and platform engineering 

- Compliance, Security, DevOps, and Risk teams

- This is a highly cross-functional role touching AI infrastructure, open banking, data pipelines, consumer UX, and systems design.

• Take full ownership of the GoConsumer full-stack codebase (React native/AWS/Amazon Bedrock).
• Establish engineering standards, testing frameworks, monitoring, and CI/CD pipelines. 
• Build a technical roadmap that aligns with product vision, compliance needs, and long-term scalability. 
• Own the integration of LLMs, fine-tuned models, vector databases, and personalisation engines. 
• Partner with ML engineers to implement retrieval pipelines, guardrails, and model-serving workflows. 
• Build evaluation (eval) pipelines for accuracy, safety, tone, hallucinations, and reasoning tests, enabling product managers to prioritise, iterate, and ship the right behaviour changes with clarity and confidence
• Ensure fast, reliable, cost-efficient model usage (token optimisation, caching, prompt engineering). 
• Implement safe execution layers for financial guidance — protecting consumers from data leakage and errors or unsafe outputs.
• Implement engagement systems such as streak engines, reward logic, missions, progress computation, and personalised challenge algorithms.
• Ensure all motivational systems are stateful, auditable, fair, and tamper-proof, especially for regulated industries.
• Build scalable rule engines that support rapid iteration by PMs and Designers.
• Architect and build reliable backend services, APIs, data pipelines, and integrations (open banking, payments, cards, lending, notifications). 
• Work with the Staff Designer to deliver high-fidelity, performant mobile experiences. 
• Maintain strict security and compliance standards for PII, financial data, and bank connections. 
• Lead QA automation, error handling, monitoring, and rapid iteration systems. 
• Implement feature flags, A/B testing, and real-time analytics instrumentation.
• Translate complex technical concepts into clear language for product and executive teams. 
• Mentor future engineers as the team grows and help hire the right engineering talent. 
• Establish engineering rituals: sprint reviews, tech debt management, reliability reviews, and roadmap planning. 
• Own operational excellence and ensure the product remains fast, safe, stable, and delightful.
• Enable the more technical product managers to build and deploy to the code base in a safe compliant manner e.g. small features/front-end fixes.

• 8+ years of engineering experience, with strong mobile/web/backend foundations and at least some exposure to fintech, data-rich, or consumer apps. 
• 2+ years experience integrating LLMs or ML-driven systems into production (fine-tuning, RAG, evals, guardrails, observability). 
• Strong understanding of AI evals, including automated test suites, acceptance criteria, and safety/quality scoring. 
• Skilled in systems architecture, API design, database schema design, and secure data handling. 
• Experience building or scaling gamified products, behavioural systems, or loyalty engines is a plus. 
• Comfortable taking ownership of an early-stage codebase and turning it into a high-quality, scalable platform. 
• Not afraid to get hands-on: you write code, debug issues, ship features, and dive into infra when needed. 
• Excellent communicator with the ability to work in a fast-moving, ambiguous, highly collaborative environment. 
• Passionate about building technology that makes real improvements to people's financial wellbeing.

Our Fantastic Benefits (varies by location)

20 to 25 days of holiday to support a healthy work-life balance

Monthly team outing allowance to enjoy social events with your colleagues

Office perks such as refreshments (coffee, sodas etc.), breakfast, fruit and snacks

Meal card to enjoy a daily lunch allowance to make your workdays even more convenient

Well being support our health allowance covers gym memberships, massages, and much more to help you feel your best

PLUS additional benefits designed to enhance your work-life experience

Shape Your Role and Make an Impact

Join a dynamic environment where you can take ownership, drive change, and continuously embrace new challenges. We're looking for dedicated and highly motivated individuals who thrive in a fast-paced environment and enjoy collaborating across different areas of the organisation.

If your skills and experience align with this role, we'd love to hear from you Apply now and submit your CV in English.