Senior Software Engineer (BackEnd) - FanDuel, Hybrid

About Betfair Romania Development​:

Betfair Romania Development is the largest technology hub of Flutter Entertainment, with over 2,000 people powering the world’s leading sports betting and iGaming brands. Exciting, immersive and safe experiences are delivered to over 18 million customers worldwide, from our office in Cluj-Napoca. Driven by relentless innovation and commitment to excellence, we operate our own unbeatable portfolio of diverse proprietary brands such as FanDuel, PokerStars, SportsBet, Betfair, Paddy Power, or Sky Betting & Gaming.

Our Values:

The values we share at Betfair Romania Development define what makes us unique as a team. They empower us by giving meaning to our contributions, and they ensure that we consistently strive for excellence in everything we do. We are looking for passionate individuals who align with our values and are committed to making a difference.

Win together | Raise the bar | Got your back | Own it | Positive impact

About FanDuel:

FanDuel is a leading force in the sports-tech entertainment industry, redefining how fans engage with their favourite sports, teams, and leagues. As the premier gaming destination in North America, FanDuel operates across multiple verticals, including sports betting, daily fantasy sports, online gaming, advance-deposit wagering, and media.

Role Overview:

We are looking for a Senior Software Engineer to join our new Casino AI Enablement engineering team in Cluj-Napoca. You are an experienced AI native engineer who designs and ships high-quality, scalable systems, and who builds software with AI as the default interface, using coding assistants, agentic workflows, and automation to develop, test, and iterate. You apply AI to accelerate delivery, improve code quality, and shape system design, with demonstrated experience delivering production-grade outcomes.

You operate autonomously, owning major product areas, driving technical direction, raising standards, and mentoring others. You bring solid expertise in Java and/or Node.js, an intuition for backend architecture, and a pragmatic, outcome-driven mindset. You default to using AI in your workflow, and apply strong engineering judgment to validate, refine, and productionalize its outputs.

You are creative, you see things from a user and business perspective to know what to focus on, and you know how to collaborate with your key stakeholders to deliver value. You will partner with colleagues across the business unit to define high-value use cases, and work closely with central engineering, data and AI teams, alongside external partners such as AWS, to design and deliver scalable, production-grade AI-powered systems.

Key Accountabilities & Responsibilities:

• Operate in an AI-first development model, using coding assistants, agentic workflows, and automation as the primary means of building, testing, and iterating on software solutions.
• Own the end-to-end design, development, and operation of scalable, high-performance backend services and APIs using Java and/or Node.js, ensuring reliability at scale for millions of users.
• Lead technical discussions, author design documents, and drive alignment across squads on architecture, patterns, and best practices.
• Champion operational excellence and on-call readiness. Address technical debt, performance issues, and reliability risks proactively.
• Mentor and support engineers through hands-on guidance, code reviews, and knowledge sharing, raising the overall engineering standard of the team.
• Drive adoption of AI practices across teams, sharing knowledge and enabling engineers and stakeholders to build and scale AI capabilities effectively.
• Partner with stakeholders to translate business needs into well-defined, scalable engineering solutions.

Skills, Capabilities & Experience Required:

AI-Augmented Development

• Hands-on experience using AI coding assistants (Claude, Cursor) and agentic frameworks as the primary interface for software development, not as occasional productivity tools.
• Proven ability to deliver significantly increased engineering throughput through effective use of AI, while maintaining high standards for correctness, security, and maintainability.
• Demonstrated experience delegating substantial portions of implementation, testing, and debugging to AI systems, with strong oversight and validation.
• Strong ability to write prompts, review AI-generated code critically, and integrate it safely into production code.
• Clear judgement of where AI tooling adds value and where human engineering judgment is non-negotiable.
• Experience building and operating monitoring and evaluation frameworks for AI systems, including metrics for model performance, output quality, data integrity, and end-to-end system reliability.
• Experience integrating LLM APIs (OpenAI, Anthropic Claude, Amazon Bedrock) into backend services.
• Demonstrated curiosity and initiative in experimenting with new models, frameworks, and prompting techniques.

Core Engineering

• 5+ years of professional backend software engineering experience.
• Strong proficiency in Java (Spring Boot) and/or Node.js for building production-grade backend systems.
• Solid grasp of software design principles: clean architecture, SOLID, DDD, event-driven design, and RESTful/GraphQL API design.
• Experience with relational and NoSQL databases (e.g. PostgreSQL, MySQL, DynamoDB, Redis) and performance tuning.
• Comfortable working in cloud-native environments (AWS preferred); experience with containerisation (Docker, Kubernetes) and IaC (Terraform).
• Familiarity with messaging and streaming platforms (Kafka, SQS/SNS).
• Strong testing culture: unit, integration, and end-to-end testing; familiarity with TDD and BDD approaches.
• Full Stack development is a plus. Knowledge of TypeScript in addition to Node.js is a plus.

Soft Skills & Ways of Working

• Strong written and verbal communication; able to explain technical decisions to both engineers and non-technical stakeholders.
• Demonstrated ability to work autonomously on ambiguous problems and drive them to resolution.
• Experience working in agile/scrum teams; comfortable with continuous delivery and iterative development; and with experimenting new ways of working.
• Track record of mentoring peers and raising the overall quality bar of a team.

Benefits:

• Hybrid & remote working options

• €1,000 per year for self-development

• Company share scheme

• 25 days of annual leave per year

• 20 days per year to work abroad

• 5 personal days/year

• Flexible benefits: travel, sports, hobbies

• Extended health, dental and travel insurances

• Customized well-being programmes

• Career growth sessions

• Thousands of online courses through Udemy

• A variety of engaging office events                        

Disclaimer:
We are an inclusive employer. By embracing diverse experiences and perspectives, we create a lasting, positive impact for our employees, customers, and the communities we’re part of. You don't have to meet all the requirements listed to apply for this role. If you need any adjustments to make this role work for you, let us know, and we’ll see how we can accommodate them.

We thank all applicants for their interest; however, only the candidates who best meet the job requirements will be contacted for an interview.

By submitting your application online, you agree that your details will be used to progress your application for employment. If your application is successful, your details will be used to administer your personnel record. If your application is unsuccessful, we will retain your details for a period no longer than three years, to consider you for prospective roles within the company.