Senior Software Engineer - Rules Platform at Wise

About the role

Responsibilities:
- Design, build and evolve the Rules Platform: reliable, scalable backend services and reusable internal libraries consumed by multiple teams (Fraud, AML, KYC).
- Lead system design and architecture decisions for distributed systems where reliability and data consistency are critical.
- Improve platform performance and reliability: set and monitor SLOs, identify bottlenecks, and implement fixes.
- Collaborate with product managers and engineering teams to prioritise features and make the platform easy to use and extend.
- Own end‑to‑end engineering initiatives from problem identification through design, implementation and delivery.
- Contribute to code reviews, mentoring, and engineering best practices.

Requirements:
- Strong hands‑on experience with JVM languages (Java or Kotlin) and building complex backend systems.
- Experience with Kafka, SQL databases and distributed system patterns focused on consistency and reliability.
- Proven experience building or maintaining internal libraries/shared components used across teams.
- Solid system design skills and confidence evaluating trade‑offs in architecture.
- Product mindset: ability to understand internal user needs and work effectively with Product Managers.
- Experience mentoring engineers and contributing to engineering excellence and documentation.

Responsibilities

You will build and evolve the Rules Platform by developing reliable, scalable backend services and reusable internal libraries. You will also drive technical architecture decisions and collaborate with cross-functional teams to improve platform performance and reliability.

Requirements

Candidates must have strong hands-on experience with JVM-based languages like Java or Kotlin and expertise in distributed systems. Experience with Kafka, SQL databases, and a strong product mindset for building internal tools are also required.

Key skills

• Java — in 309 other listings on The Stack
• Kotlin — in 242 other listings on The Stack
• JVM — in 11 other listings on The Stack
• Kafka — in 150 other listings on The Stack
• SQL — in 484 other listings on The Stack
• Distributed systems — in 306 other listings on The Stack
• System design — in 187 other listings on The Stack
• Backend development — in 155 other listings on The Stack
• Internal libraries
• Risk assessment
• Performance monitoring
• Mentoring
• Technical architecture
• Data consistency
• FinTech
• Risk management

On The Stack (as of 2026-10-22)

• Wise has 39 other listings on The Stack, 37 of them marked as offering visa sponsorship.
• 133 visa-sponsored software engineer jobs in Europe on The Stack, posted in the last 60 days.

Frequently asked questions about Wise

Is this Senior Software Engineer - Rules Platform role still open?

It was posted on 2026-10-21 and is listed as active on The Stack. Confirm on Wise's application page before applying.

Does Wise offer visa sponsorship?

This listing is marked as offering visa sponsorship. Eligibility rules are set by the employer, so check the details on Wise's site.

Where is this role located?

The listing gives the location as Tallinn, Estonia. It is marked on-site.

What skills does this role ask for?

The listing names: Java, Kotlin, JVM, Kafka, SQL, Distributed systems, System design, Backend development, Internal libraries, Risk assessment, Performance monitoring, Mentoring, Technical architecture, Data consistency, FinTech, Risk management.