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Software Engineer (Full Stack)

Callsign

Responsibilities

  • Design, build, and maintain scalable Java-based backend services and modern frontend web applications.
  • Develop robust RESTful APIs and integrate frontend interfaces seamlessly with backend systems.
  • Build responsive, accessible, and performant user interfaces using modern web frameworks.
  • Write clean, testable, and maintainable code across the full stack following engineering best practices.
  • Collaborate closely with Product Managers, UX/UI Designers, QA, and platform teams to translate user requirements into technical solutions.
  • Participate in peer code reviews, contribute to architectural discussions, and proactively address technical debt.
  • Support deployment pipelines, troubleshoot production issues across frontend and backend layers, and drive continuous improvement.

Requirements

  • 3–6 years of commercial full-stack software development experience.
  • Strong backend expertise in Java, Spring Boot, and RESTful API design; gRPC experience is a plus.
  • Hands-on frontend experience with modern JavaScript or TypeScript frameworks, preferably React. Commercial experience with Vue.js or Angular is also welcome.
  • Proficiency in JavaScript, HTML5, CSS3/SCSS, and responsive UI design.
  • Working knowledge of frontend build tools and package managers such as Vite, Webpack, npm, or yarn.
  • Solid experience with relational databases such as MySQL, PostgreSQL, or Oracle, and SQL query writing.
  • Strong understanding of OOP fundamentals, SOLID principles, and data structures and algorithms.
  • Familiarity with testing frameworks across the stack, such as JUnit, Mockito, Jest, React Testing Library, or Cypress.
  • Familiarity with Docker, Linux environments, and CI/CD pipelines.
  • Exposure to microservices architecture.
  • Awareness of secure coding practices including OWASP Top 10, XSS, CSRF prevention, and secure authentication/token management.
  • Strong communication, analytical thinking, and collaboration skills.

Preferred

  • Experience with Java 17 and Spring WebFlux with Project Reactor, or Java 21+ Virtual Threads.
  • Production experience with NoSQL systems such as DynamoDB.
  • Production experience with TypeScript and modern frontend state management such as Redux Toolkit or Zustand.
  • Familiarity with design systems, component libraries, and tools like Storybook or Figma.
  • Production experience with microservices architecture, distributed caching with Redis, and event streaming with Kafka.
  • Familiarity with container orchestration, Kubernetes, Helm, and cloud platforms such as AWS or GCP.
  • Familiarity with observability and monitoring tools such as Prometheus, Grafana, OpenTelemetry, or Elastic Stack.
  • Basic understanding of web accessibility and web performance optimisation

Benefits

  • Pension scheme with Scottish Widows
  • Private medical cover with Vitality
  • Life assurance (4x base salary)
  • Personal Learning & Development Budget
  • Cycle to Work Scheme
  • Company Family Leave
  • 25 days annual leave plus Callsign Bank Holiday
  • Employee Volunteering Program

Workplace

hybrid

Department

Engineering

Role details

Callsign · London, United Kingdom (Hybrid) · Full-time · Posted 2026-10-05

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