Senior Software Engineer (Java) - Authentication Engine

This is Adyen

Adyen provides payments, data, and financial products in a single solution for customers like Meta, Uber, H&M, and Microsoft - making us the financial technology platform of choice. At Adyen, everything we do is engineered for ambition.

For our teams, we create an environment with opportunities for our people to succeed, backed by the culture and support to ensure they are enabled to truly own their careers. We are motivated individuals who tackle unique technical challenges at scale and solve them as a team. Together, we deliver innovative and ethical solutions that help businesses achieve their ambitions faster.

Authentication Engine

You will be joining the core team responsible for the Authentication Engine, a mission-critical platform within Adyen’s larger Uplift product suite.

What We Do

The core job of the Authentication Engine is to ensure secure, compliant, and frictionless customer authentication for every transaction. While we currently handle essential components like 3D Secure (3DS) authentication, we are rapidly evolving the platform into a true multi-modal authentication hub.

The Innovation

Our vision is to move beyond traditional methods. You will be building a platform that integrates and manages a diverse range of next-generation authentication solutions, including various Passkey implementations and Digital Wallet verification.

The key differentiator is our Machine Learning Optimization Model. This model sits at the heart of the engine, analyzing real-time data to dynamically select the single best available authentication method from the compliant options, optimizing for:

• Highest conversion rates (Uplift).
• Lowest fraud risk.
• Best possible user experience.

What you'll do

This isn't just a backend service; it’s a high-stakes, high-volume challenge that demands scalability, resilience, and precision.

• Global Reach: The decisions made by our engine directly influence the success of transactions for the world's largest merchants.
• Complex Constraints: Our work is heavily driven by evolving global compliance and regulatory requirements (e.g., PSD2, SCA), requiring meticulous engineering and design.
• Intelligent Routing: The authentication decisions you build feed directly into Adyen's Intelligent Payment Routing, making this product an indispensable part of our core financial infrastructure.

You will be engineering the critical layer that blends cutting-edge ML decision-making with unbreakable financial compliance, defining the future of secure commerce.

Who You Are:

• A Senior Software Engineer with experience working with object-oriented programming languages (Java).
• We launch fast and iterate often. Concretely, this means that within your first few weeks, you will bring code live that impacts many businesses and shoppers.
• You will be fully responsible from its initial design to bringing new functionality live.
• Identify and improve parts of the platform to make it more robust and scalable.
• You enjoy and have previous experiences mentoring (not managing) developers.
• Collaborate across teams and time zones to make things happen, review code and be open to feedback.
• You have a deep understanding of the why, how, and where of architectural software design.
• You are a clear and concise communicator capable of articulating complex, technical concepts to both junior developers and non-technical peers.
• You are flexible, a team player, and someone who understands the bigger picture.
• You are able to take ownership and lead a project.
• We are an international team and our working language is English, so you speak it fluently in both technical and non-technical contexts.
• Our Tech Stack: Java 17+, Web Services (RESTful) and SQL/PostgreSQL using MyBatis (ORM), Tomcat, Gradle, Kafka, CockroachDB, Cassandra, and Elasticsearch.

This role is based out of our Amsterdam office. We are an office-first company and value in-person collaboration; we do not offer remote-only roles.

Our engineers are building the first financial technology platform that combines payments, data, and financial services. We’re looking for more talented problem solvers to help us address a unique set of challenges.