Full Stack Engineer (Java & React)

Quick Facts

• Role: Full Stack Engineer (Java & React)

• Focus: End-to-end feature development and quality/testing for a digital asset servicing platform

Description

You will design, build, and test features end-to-end with full ownership of code and quality, working across development and test automation. The role combines Java backend development with modern React frontend development, including API integration and automated testing (unit, integration, and Cucumber end-to-end tests). You’ll also support test-first practices, performance/scalability considerations, and monitoring through instrumentation and logging.

Responsibilities

• Design, develop, and maintain features using Java and React

• Build responsive, modern frontend applications with React

• Develop and integrate APIs and web services

• Work with relational databases (Oracle, Postgres)

• Write clean unit tests (JUnit or equivalent) alongside application code

• Contribute to automated test framework using Ruby and Cucumber

  • Write new Ruby step definitions as needed

  • Create and maintain Cucumber feature files for end-to-end testing

• Write automated tests for features delivered by other engineers to reduce development bias

• Champion a test-first approach

• Apply performance and scalability considerations; use JMeter for load/performance testing when required

• Embed instrumentation, configuration, and logging to support monitoring and ongoing support

• Analyse and debug issues using logs; propose and implement fixes

• Collaborate in Agile ceremonies and help the squad plan effectively

• Partner with product managers and analysts to implement functional and non-functional requirements

• Adopt a product mindset focused on client impact, configurability, and long-term supportability

Requirements

• Proficiency in Java with strong JUnit (or equivalent) testing experience

• Proficiency in React and associated unit testing frameworks

• Experience with Ruby scripting for Cucumber step definitions

• Experience with Cucumber for end-to-end testing

• Strong understanding of multi-threading, parallel processing, and real-time messaging

• Experience with test-first design and CI/CD practices

• Ability to use JMeter (or similar) for performance testing (a plus)

• Practical awareness of cloud services (databases, servers, storage, gateways)

• Ability to use AI-assisted engineering tools (e.g., GitHub Copilot, ChatGPT) while maintaining code quality and critical thinking

• Familiarity with financial markets concepts (corporate actions lifecycle knowledge preferred)

• Strong analytical and debugging skills

• Clear communication and ability to explain trade-offs to technical and business audiences

Benefits

• Hybrid B2B cooperation with the option to provide services from the Warsaw office as agreed based on project needs.

Recruitment Process

• HR Interview

• Technical Interview

• Client Interview

• Feedback and offer