Java Software Engineer

Harrington Starr; Greater London; Hybrid; GBP 90,000 - 120,000; Full time

Job summary

Harrington Starr in London is seeking a Java Engineer to join a fintech's institutional trading tech team. You’ll help build high-performance trading APIs used by global markets, focusing on performance, reliability and resilience.

You'll work on asynchronous, event-driven systems, multithreaded architectures and external API integrations, with AWS-based cloud development and close collaboration with product and business stakeholders. Hybrid work, three days onsite.

Qualifications

• 5+ years of Java development experience.
• Strong Java and Spring/Spring Boot expertise.
• Experience with multithreading and concurrency.
• Experience with asynchronous messaging or streaming systems.
• Experience building external APIs and AWS or cloud environments.

Responsibilities

• Build and develop trading APIs used by institutional clients.
• Work with asynchronous, event-driven and messaging systems.
• Create resilient external APIs and integrations.
• Improve performance, reliability and automation across the platform.
• Collaborate with product and business stakeholders.
• Participate in cloud-based development, predominantly AWS.

Skills

Java

Spring Boot

Multithreading

Asynchronous Systems

External APIs

AWS

Job description

Java Engineer – Institutional Trading | London | Hybrid

I’m working with a leading global fintech that is expanding its institutional trading technology team and looking for a Java Engineer to help build a new generation of high-performance trading APIs.

You’ll join a team responsible for connectivity between institutional clients and global markets, working on systems where performance, reliability and resilience genuinely matter.

What you’ll be working on:

• Building and developing trading APIs used by institutional clients
• Working with asynchronous, event-driven and messaging systems
• Building resilient external APIs and integrations
• Improving performance, reliability and automation across the platform
• Working closely with product and business stakeholders
• Cloud-based development, predominantly AWS

What we’re looking for:

• Around 5+ years of Java development experience
• Strong Java and Spring/Spring Boot
• Multithreading and concurrency experience
• Experience with asynchronous systems, messaging or streaming
• Experience building external APIs
• AWS or other cloud experience
• Financial markets/trading experience is highly advantageous

Location:

London – hybrid, 3 days per week onsite

Strong opportunity for a Java engineer looking to move closer to institutional trading and work on performance-sensitive systems used directly by financial markets clients.