Fraud Specialist

🏢 Summary: Senior Engineer role focused on building and optimizing a high-performance fraud detection platform processing tens of millions of devices and thousands of events per second. The position involves designing scalable, reliable data pipelines and distributed systems to deliver real-time decisions within milliseconds. The engineer owns system performance, scalability, and architecture in a large-scale production environment. 🗂️ Requirements: 5+ years experience in high-tech or startup environments, Experience with event-driven architecture, Experience designing and operating large-scale production systems (TB or PB scale), Strong background in distributed systems and fault-tolerant architectures, Proficiency in Rust or comparable systems languages (C++ or Go), Experience with data processing pipelines (stream and batch), Experience with message queues or buses, Experience with observability practices, Experience with container orchestration platforms, Understanding of distributed systems algorithms (consensus, MapReduce, fault tolerance), Education equivalent to Bachelor’s degree in Computer Science 📃 Skills: Rust, C++, Go, Kafka, NATS, Kubernetes, AWS, MapReduce, Consensus, Sharding, Autoscaling, Observability, Telemetry, Tracing, DistributedSystems, StreamProcessing, BatchProcessing 🏢 Description: The Mission Your mission as Senior Engineer is to drive the improvement of the platform, making the product extremely fast, scalable, reliable and easy to operate. The results will be directly reflected in the fraud prevention metrics, dependent business variables (revenue, margin) as well as valuation of the company and your personal stock option pool. Your code will be used to process data from more than 50M devices, creating decisions within milliseconds on top of thousands of events per second. You will collaborate with other engineers, founders, product managers, research team (building the ML/AI models), platform team and other fraud-fighters in the company. General Seniority: 5+ years experience in a high-tech/startup universe Employment Type: Employee or Contractor (just technicality, the spirit is that it’s “Engineer, Fraud-Figher & Shareholder“ anyway) Schedule: Full-time Work Arrangement: Full remote possible, with availability for in-person gatherings, collaboration sessions as well as team-buildings Responsibilities Design, implement, optimize, monitor Data retrieval and storage Data processing pipeline (stream processing, batch processing) … any other relevant code to catch fraudsters Collaborate with product managers, research, and other engineers to understand requirements and translate them into well-defined technical specification. Ownership of ensure the scalability, reliability, and performance of the product Mentor and guide other engineers Ensure compliance with relevant data protection regulations and standards Preferred experience Experience Experience with event-driven architecture (asynchronous, message passing, …) Experience designing, building and operating large-scale production systems (Peta or at least TB scale) (data storage with fault-tolerance, sharding, auto-scaling) Experience with both high-level and low-level programming languages Experience in Rust or comparable systems languages (C/C++, Go); willingness to become a Rust expert if not already.​ Experience with building and operating distributed architecture (observability, ….) Foundational algorithms/papers used in this space (map reduce, consensus, fault tolerance, synchronization, leader election, gossip …) Message queues/buses (Kafka/NATS/….) Observability (logs, telemetry, tracing, …) Orchestration (kubernetes) Attitude Passion for building great software, that solves real problem of real people Skills (to be verified) Education/skills/understanding equivalent to Bachelor's degree in Computer Science (acquired by any means) Excellent communication and presentation skills (expressing clearly, maximizing information to data ratio) Strong problem-solving skills and the ability to think critically System of values compatible with ThreatMark (applies for all positions): Extreme Ownership: Taking initiative, driving results, and passionately owning project outcomes Deep Understanding: Preference of deeply understanding topics and systems from first-principles over opinions, guesses and superficial Integrity: Consistently adhering to strong moral and ethical principles, acting with honesty, accountability and transparency Collaboration: Building positive, efficient relationships, expressing in precise and efficient way Innovation and Adaptability: Continuously seeking improvement, being open to new ideas, and making data-driven decisions Nice to Have: Experience in the US fintech environment Experience with cloud platforms such as AWS Experience with programming in Rust Knowledge of statistical analysis and ML Experience in the Cybersecurity domain Previous experience in a startup environment Leadership skills and passion to help other people perform at their best

🏢 Summary: Senior Software Engineer role focused on building and scaling backend systems for real-time and post-transaction fraud detection within a microservices, event-driven architecture. The position involves designing APIs and services, improving system reliability, and collaborating cross-functionally to deliver scalable fraud tooling. Fully remote role based in Poland with on-call responsibilities. 🗂️ Requirements: 5+ years backend development experience, Experience building scalable systems in Python or Kotlin, Experience with distributed systems, Experience with AWS cloud infrastructure, Experience with MySQL or PostgreSQL, Experience with Kubernetes, Strong system design skills, Proficiency in SQL, Experience with CI/CD pipelines, Willingness to participate in on-call rotation 📃 Skills: Python, Kotlin, AWS, MySQL, PostgreSQL, Kubernetes, SQL, CI/CD, Snowflake, dbt, Airflow, Chronosphere 🏢 Description: Affirm is reinventing credit to make it more honest and friendly, giving consumers the flexibility to buy now and pay later without any hidden fees or compounding interest. The Fraud Engineering organization builds the foundational and tactical software that enables Affirm to respond strategically to fraud—both in real time and after the transaction. Our mission is to support business growth while protecting Affirm, our buyers, and our merchants. We evaluate risk at critical decision points in the user journey, rapidly adapt to evolving fraud patterns, and equip operations teams with the tools needed to investigate and mitigate fraud at scale. We’re looking for a Senior Software Engineer to join our fully remote team based in Europe. You’ll collaborate closely with stakeholders across North America—including teams in Product, Compliance, Machine Learning, Fraud Operations, Fraud Strategy, and other Fraud Engineering teams. What You'll Do You will be responsible for owning and delivering quarterly goals for your team, leading engineers through ambiguity to solve open-ended problems, and ensuring that everyone is supported throughout delivery. You will design and implement backend services and APIs using Python or Kotlin, operating within Affirm’s microservice and event-driven architecture. You will take an active role in shaping the team’s roadmap, collaborating on technical design, and driving execution across projects that span multiple teams. You will partner with the Engineering Manager and your teammates to elevate quality standards, evolve engineering processes, and represent the team in cross-functional initiatives. You will collaborate cross-functionally with stakeholders in Fraud Ops, Compliance, Product, Machine Learning, and Analytics to build scalable fraud tooling and infrastructure. You will proactively identify opportunities to improve system reliability, team efficiency, or architecture—and lead efforts to address them. You will contribute to operational excellence by maintaining high observability standards, responding to incidents, and participating in the on-call rotation. You will foster a culture of ownership, inclusion, and craftsmanship by mentoring teammates, providing feedback, and upholding high code and design standards. On-Call Rotation - There would be an on-call rotation for this role as a requirement. What We Look For 5+ years of experience building backend systems at scale using Python or Kotlin. Experience with distributed systems and infrastructure using AWS, MySQL/PostgreSQL, and Kubernetes. Strong system design skills and a track record of delivering maintainable, extensible services. Proficiency in SQL and working with data-rich environments. Familiarity with CI/CD practices and safe production deployments. Strong written and verbal communication skills, especially in distributed teams. A proactive, ownership-driven mindset with a focus on learning and team success. Experience with Snowflake, dbt, Airflow, or Chronosphere (nice to have) Background in fraud prevention, risk systems, or post-transaction tooling. (nice to have) Experience working in the fintech sector or other highly regulated environments, with a strong understanding of risk, compliance, and operational constraints. (nice to have) Compensation & Benefits Base Pay Grade - N Equity Grade - 4 Employees new to Affirm typically come in at the start of the pay range. Affirm focuses on providing a simple and transparent pay structure which is based on a variety of factors, including location, experience and job-related skills. Base pay is part of a total compensation package that may include monthly stipends for health, wellness and tech spending, and benefits (including 100% subsidized medical coverage, dental and vision for you and your dependents). In addition, the employees may be eligible for equity rewards offered by Affirm Holdings, Inc. (parent company). POL base pay range per year: 301,000 zł  -  401,000 zł Additional benefits include: Flexible Spending Wallets for tech, food and lifestyle Away Days - wellness days to take off work and recharge Learning & Development programs Parental benefits Employee Resource & Community Groups This role is eligible for creative tax benefits, subject to applicable law and company policy Location - Remote Poland The majority of our roles can be located anywhere in Poland. This job description is not a contractual document, and is not intended to have binding force.