Senior Java Developer

Synnovate; City Of London; On-site; GBP 90,000 - 120,000; Full time

Job summary

Synnovate is seeking a Senior Java Developer to design, develop and maintain Java-based applications across in-house systems, APIs and client portals. You will contribute to the full software lifecycle from concept to deployment in a capital markets context, focusing on high-quality software and scalable solutions.

The role includes mentoring a team of developers, collaborating with IT and business stakeholders, and advancing cloud-native, automated testing and CI/CD practices in a dynamic

Qualifications

• 6+ years' Java development in financial services.
• Proficiency in Java 11+ and Spring/Spring Boot.
• Experience with TDD, Agile, and CI/CD.
• Knowledge of capital markets.

Responsibilities

• Design, develop, and maintain in-house Java systems and APIs.
• Customise third-party trading systems to meet business needs.
• Write clean, tested code with SOLID and design patterns.
• Apply TDD/BDD and maintain test coverage with JUnit, Spock, Mockito.
• Mentor and lead a team of Java developers.
• Collaborate with IT and Business stakeholders to propose solutions.

Skills

Java development

Java 11+

Spring Boot

Capital markets

TDD/Agile

CI/CD

JUnit/Spock

Mockito

Git & Maven

Tools

JUnit

Spock

Mockito

Git

Maven

Job description

Senior Java Developer

My customer is actively hiring a talented & eager Senior Java Developer to join their growing & 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.

Role Overview

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. 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.

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

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