Senior Back-End Engineer

Overview of the Role

We are looking for a skilled Senior Backend Developer with experience in .NET to join our team. You will work on building and maintaining scalable backend applications and services, contributing to a robust and high-performance infrastructure that powers a seamless user experience across our platforms.

You will develop backend services in .NET and support/improve existing systems as needed. You'll collaborate closely with other engineers, participate in technical discussions, and help evolve our backend architecture and best practices.

You will own the performance and stability of the backend services: ensure all APIs operate efficiently, proactively identify and resolve issues, drive rapid incident resolution, and be accountable for service reliability, uptime, and seamless integration. This role is ideal for someone who enjoys clean, maintainable code, API design, and continuous improvement. Experience with distributed systems, microservices, state management, and performance optimization is highly valued. Familiarity with cloud technologies, message brokers (e.g., Kafka), and caching systems (e.g., Redis) is a strong advantage. This role follows a hybrid approach to working, allowing you to combine working from home with working in our modern offices.

You and your manager will agree on the best working pattern that suits both of you. We'll kit you out to work remotely, but we know that collaboration is key to our success, and spending quality time together helps us stay aligned with our mission.

What you'll do:  

• Develop and maintain scalable backend services and APIs using .NET

• Collaborate with developers, DevOps engineers, product owners, and other stakeholders to deliver robust and secure backend solutions

• Participate in technical design discussions and continuously improve backend architecture and performance

• Design and implement RESTful APIs and integrations, including real-time features (e.g., WebSockets) when needed

• Integrate with databases (SQL and NoSQL), message brokers, third-party services, and external APIs

• Write clean, reusable, and testable code, Unit tests and help maintain high standards for code quality through reviews

• Debug and optimize backend systems for performance, scalability, and security

• Maintain technical documentation and API guidelines

• Perform related duties as assigned

What you'll bring: 

• 5+ years of professional software engineering experience, with strong hands-on in backend development

• 5+ years of backend experience in .NET

• Solid experience designing and integrating RESTful APIs

• Strong grasp of backend architecture, scalability, microservices, and API security best practices

• Proficiency with Git and collaborative workflows (GitHub/GitLab); familiarity with Agile processes

• Experience with testing (unit, integration, end-to-end) using tools such as xUnit, NUnit

• Familiarity with CI/CD pipelines

• Experience with cloud platforms (preferably AWS)

Knowledge:

• Deep expertise in .NET

• Experience optimizing backends for scalability, maintainability, and performance

• Good grasp of microservices, distributed systems, and asynchronous processing (queues; Kafka/RabbitMQ)

• Understanding of authentication and authorization mechanisms (OAuth2, JWT, OpenID Connect)

• Knowledge of relational (PostgreSQL, MySQL) and non-relational (MongoDB, Redis) databases

• Proficient with Git and collaborative Git-based workflows. Experience with monorepo setups is a plus

• Understanding of security principles for web and API development

• Familiarity with infrastructure as code tools (e.g., Terraform, CloudFormation) is a plus

• Proficient in written and verbal English communication

Personal Attributes

• Analytical and synthesis skills

• Problem-solving skills

• Autonomy and resourcefulness

• Sense of initiative

• Attention to detail

• Flexibility in organizing work

• Leadership and mentorship abilities

• Strong decision-making and ownership mindset

• Ability to work as part of a team

• Ability to adapt to change

• Results driven.

About Flutter CEE

We are Flutter Central & Eastern Europe (CEE). As a proud member of the Flutter family - a global leader in sports betting and iGaming - we are building one of the Group's most dynamic tech and product hubs in Central and Eastern Europe. We aren't just here to participate.

We're here to change the game. By uniting local powerhouses like MaxBet, Adjarabet.com, and Adjarabet.am, we combine deep regional expertise with the scale and strength of Flutter's global platforms. We're setting a new standard for entertainment, responsibility, and innovation - powered by real customer signals that shape everything we build. Settling for the status quo isn't in our DNA.

We build systems designed to scale. We're moving faster, thinking bigger, and putting our customers exactly where they belong: at the heart of every decision. We start by listening to our customers and the communities we serve. What we see, hear, and learn become clear signals, and those signals quickly shape product decisions, better experiences, and responsible innovation.

Technology powers our ambition. The Signature System - our operating model - makes our signal-led approach repeatable and scalable across markets. It's how we move fast and grow with confidence. As part of Flutter, we benefit from the Group's collective advantage - the Flutter Edge. It allows us to identify success in one market, replicate it across brands, and implement proven ideas quickly - with customers always at the forefront.

We're a team of thousands, driven by a challenger mindset and a shared commitment to lead.

We are shaping the future of iGaming in Central and Eastern Europe right here, right now, and our technology and product teams are defining what responsible innovation looks like in practice - not just in theory.

We are Flutter Central & Eastern Europe (CEE). Built on experience. Built to lead. Local champions. Global infrastructure. Why choose us At Flutter CEE, people have access to vast opportunities for career growth and self-development.

Our employee benefits package goes far beyond offering the minimum: We support our people in becoming their best version at work and beyond - and our benefits reflect that commitment.   These are some of the benefits included in our employee package:  

• Generous annual leave 

• Hybrid work

• Individual health insurance 

• Paid sick leave 

• Paid maternity & paternity leave 

• Family reward

• Performance & referral bonuses 

• Loyalty award