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full time
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Senior Java Developer

SynnovateFarringdon, Central London🇬🇧United KingdomPosted 21 Jul 2026

Quick Overview

Work Type
Hybrid
Schedule
Full Time
Level
Mid Senior

Job Description

Senior Java Developer<br />My customer is actively hiring a talented &amp; eager Senior Java Developer to join their growing &amp; dynamic team. The successful candidate will be responsible for designing, developing, and maintaining Java-based applications, contributing to the full software development lifecycle from concept to deployment and beyond. This role is ideal for a passionate and seasoned Senior Java Developer looking to further their career in a challenging and rewarding environment.<br />Role Overview<br />You will work on in-house systems, APIs, client reporting and web portal, as well as customising our third-party trading system. You will translate complex business requirements into scalable, high-quality software solutions.<br />This is an opportunity to deepen your expertise in a capital markets environment as a Senior Java Developer while taking on team leadership and mentoring responsibilities — with direct exposure to cloud-native infrastructure, advanced Java development, AI and a highly collaborative engineering culture.<br />Key Responsibilities

  • Design, develop and maintain in-house systems, APIs, reporting tools and the client web portal
  • Customise and extend third-party trading systems to meet business requirements
  • Write clean, well-tested code following SOLID principles, Design Patterns and Clean Code practices
  • Apply TDD and BDD methodologies; maintain test coverage using JUnit, Spock and Mockito
  • Participate in code reviews and contribute to continual improvement of engineering standards
  • Manage and mentor a team of Java (and other) developers, supporting growth and career development
  • Liaise with various stakeholders (IT and Business) to understand requirements and propose solutions to senior stakeholders<br />Essential
  • 6+ years' Java development experience at a Financial Services company
  • Java 11+, Spring/Spring Boot, multi-threading, profiling, performance tuning, RMI
  • Capital Markets knowledge or similar
  • Experience in high-quality software practices: TDD, Agile, automated builds/deployments
  • Strong knowledge of CI build and deployment management tools
  • Experience with test frameworks (JUnit/Spock) and mocking libraries (e.g. Mockito)
  • Proficiency with Git and Maven<br />Senior Java Developer

Skills

Spring
Spring Boot
TDD
Agile
BDD
Git
JUnit
Java

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