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Senior Software Engineer (kotlin/Rust)

London Area, United Kingdom on site

About the Role

The Role

As a Senior Software Engineer, you will be on the front lines of building core product capabilities and infrastructure from scratch. You will take ownership of complex technical problems, architect production-grade services, and help set the bar for code quality, testing, and system reliability across the business.

This is a high-autonomy, greenfield environment ideal for engineers who enjoy navigating ambiguity, designing distributed systems, and building rather than maintaining legacy systems.

What You’ll Be Doing

  • Greenfield Delivery: Write clean, production-ready, testable code to build resilient, high-throughput payment systems from 0 to 1.
  • System Design & Architecture: Drive technical design for new domain services, focusing on scalability, security, and low latency.
  • Technical Standards: Establish best practices for testing, continuous integration/deployment (CI/CD), observability, and code reviews.
  • Product & Domain Collaboration: Work closely with Product Managers and Engineering Leads to break down complex business problems into clear technical roadmaps.
  • Cultural Influence: Help shape how teams ship software, evaluate new technologies, and make build-vs-buy decisions early in the organisation's lifecycle.
  • Mentorship: Elevate the technical bar of the engineering team through peer code reviews, pair programming, and architectural guidance.

Technology & Mindset

Core Stack:

  • Backend: Rust, Kotlin
  • Frontend: TypeScript
  • Platform / Tooling: Golang, Python

Tech Philosophy: You do not need deep, day-one expertise in every single language in the stack. What matters most is strong computer science fundamentals, system design capabilities, and a pragmatic "right tool for the job" mindset. The hiring process (including a take-home technical exercise) evaluates engineering judgment, code quality, and problem-solving over syntax memorization.

What We’re Looking For

  • Proven Track Record: Solid experience as a Senior Software Engineer working on production-grade, high-scale software systems (preferably in fintech, payments, or cloud-native digital products).
  • Core Engineering Strength: Strong fluency in strongly typed languages (e.g., Kotlin, Java, Rust, Go, C++) with an eagerness to work with Rust and Kotlin in production.
  • Distributed Systems Fundamentals: Experience with event-driven architectures, API design, data consistency, high availability, and cloud-native infrastructure.
  • 0-to-1 Mindset: Ability to thrive in an environment where foundations are still being laid—bringing structure without adding unnecessary friction.
  • Quality Orientation: A strong belief in automated testing, CI/CD automation, and operational ownership.

Requirements

Senior Software Engineering Experience

Solid experience as a Senior Software Engineer working on production-grade, high-scale software systems.

Fluency in Strongly Typed Languages

Strong fluency in languages like Kotlin, Java, Rust, Go, or C++.

Distributed Systems Knowledge

Experience with event-driven architectures, API design, and cloud-native infrastructure.

Quality Orientation

A strong belief in automated testing and CI/CD automation.

Nice to Have

Fintech Experience

Experience in fintech, payments, or cloud-native digital products is preferred.

Mentorship Skills

Ability to elevate the technical bar of the engineering team through mentorship.

Benefits

Hybrid Work Model

Flexible working arrangements with a hybrid model.

Career Growth Opportunities

Opportunities to influence technical architecture and engineering culture.

Apply Now
Posted9/24/2026
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