Principal Software Engineer

Powering the world’s payments ecosystem

ACI powers the payments ecosystem – globally, and you power ACI. You’ll innovate, collaborate, and grow – in an energetic technology culture with decades of proven success. ACIers – in all roles and levels – are truly your colleagues and many are your friends.

Our size and reach allow you to see the global impact of your work. You are visible, your talents are valued, and you are empowered to shape the future of payments.

As a Principal Software Engineer in Timisoara, Romania you will join a diverse, passionate team, dedicated to powering the world’s payments ecosystem!

This role will be part of the PRM product, a Fraud Detection engine, based on neural networks and database rules. It is used by banks and financial institutions to identify financial transactions sent by fraudsters instead of legitimate cardholders, based on configurable rules and spending patterns. It is designed for maximum performance and availability, being able to process thousands of online transactions per second.

We are looking for a Principal Software Engineer to lead the design and development of high‑performance, scalable software systems used in mission‑critical environments. This role requires deep expertise in Java backend development , and strong software design skills. ML engineering and/ or DevOps knowledge is considered a strong plus.

If you are interested in helping people protect their money from fraudsters and passionate about bui