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Java Senior Developer - Core Services

00071117701

Java Senior Developer - Core Services

Location: London, UK
Employment Type: Full-time
Work Model: Hybrid

About the Role
The Senior Developer, Core Services role is focused on building and supporting highly scalable backend systems for live and Video on Demand streaming services. The developer will work primarily with Java and Spring, developing end-user applications and scalable APIs while contributing to technical direction, architecture/design decisions, production support, system reliability, and continuous improvement.

The role also requires ownership of functional and non-functional quality, particularly security, resiliency, and performance, along with strong collaboration across development, architecture, and other teams.


In this role, you will:

  • Develop and maintain components using Java and Spring, covering new features, fixes, enhancements, and existing functionality.
  • Build well-tested, robust and reliable code, including handling edge cases and usability considerations
  • Identify production/code issues and use appropriate debugging techniques and tools for resolution.
  • Support non-functional testing, including performance, resiliency, and security considerations.
  • Maintain and support AWS infrastructure, Kubernetes deployments, AWS Keyspaces, Redis and Kafka.
  • Review peer code and ensure adherence to coding standards and engineering best practices.
  • Propose technical solutions and make design decisions for complex, scalable systems.
  • Collaborate with developers, architects, and analysts to understand requirements and deliver solutions.
  • Participate in stand-ups and other Agile/team ceremonies and contribute to continuous improvement.

What You Need to Have to Be Considered

The ideal candidate will have strong experience in backend software engineering and cloud-native application development, with expertise in the following areas:

  • Strong hands-on experience in Java and Spring Framework development.
  • Proven experience building web applications and RESTful APIs.
  • Solid understanding of event-driven architectures, including Kafka, asynchronous messaging, and distributed systems.
  • Experience working with AWS and AWS-native cloud services.
  • Strong knowledge of database and persistence technologies such as Cassandra/AWS Keyspaces, Redis, and PostgreSQL/DSQL.
  • Experience with containerization and orchestration technologies, including Docker and Kubernetes.
  • Hands-on experience with CI/CD pipelines, particularly using GitHub Actions and modern software delivery practices.
  • Experience with automated testing frameworks and a good understanding of non-functional requirements such as performance, scalability, security, and reliability.
  • Proficiency with Unix/Linux environments and Bash scripting.
  • Experience designing and implementing scalable, resilient software solutions.
  • Strong engineering fundamentals, including debugging, code reviews, system reliability, and software development best practices.

Additional eligibility requirements:

· Candidates must currently reside in the UK.

· Candidates must be available to start within 4 weeks of receiving an offer.

These Will Help You Stand Out

  • Observability: Datadog, Prometheus and Grafana.
  • AI/ML technologies: SageMaker, Azure and Gemini LLMs.
  • Confidence with AI-assisted / agentic software development.
  • Broader understanding of relevant technologies and modern software architecture.
  • Strong cross-team collaboration and communication skills.
  • Self-driven attitude with an interest in continuously learning new technologies, frameworks and engineering practices.
  • Creative thinking, analytical ability and attention to detail.

About Cognizant
Cognizant (Nasdaq: CTSH) is an AI Builder and technology services provider, bridging the gap between AI investment and enterprise value by building full-stack AI solutions for our clients. Our deep industry, process and engineering expertise enables us to build an organization’s unique context into technology systems that amplify human potential, drive tangible outcomes and keep global enterprises ahead in a fast-changing world. See how at cognizant.ai or @cognizant.

Additional employment information
Compensation information is accurate as of the date of this posting. Cognizant reserves the right to modify this information at any time, subject to applicable law.

Applicants may be required to attend interviews in person or by video conference. In addition, candidates may be required to present their current state or government issued ID during each interview.

Cognizant is an equal opportunity employer. Your application and candidacy will not be considered based on race, color, sex, religion, creed, sexual orientation, gender identity, national origin, disability, genetic information, pregnancy, veteran status or any other characteristic protected by federal, provincial or local laws.

Benefits that help you thrive and grow

Our benefits program is built with you in mind—so you can enjoy a fulfilling, balanced and healthy life.

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Financial wellbeing

We regularly review market data to ensure compensation reflects the value you bring. Your benefits extend beyond pay and may include retirement plans, financial education, etc.

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Physical and mental health

We empower you to prioritize your wellbeing through paid time off, flexible working where possible, healthcare plans, counselling, our Mental Health Allyship program and more. 

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Your career, your way

With 350,000+ roles at Cognizant, you’ll have opportunities explore new technologies, industries and locations—and build the skills you need to grow your career.

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Real-world impact

Think about the biggest brands you rely on. Chances are, they rely on us to help strengthen their business. Here, you’ll turn bold ideas into solutions that improve lives everywhere.

Your path to Cognizant

Here’s what you can expect from our hiring process. Please keep in mind that it may vary by role and location. Explore our FAQs to learn more.

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Step 1: Apply to the right opportunity

Find an open role that matches your skills and career goals and show us why you’re the person for the job. Don’t see the right opportunity? Consider joining our Talent Community.

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Step 2: Connect with your recruiter

If one of our recruiters sees a fit, they’ll set up a short intro call to learn more about you and how your experiences and skills match the role.

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Step 3: Show off your skills

If you and our team would like to continue the process, you’ll interview with our hiring team. Some roles may also require technical assessments and/or client interviews.

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Step 4: Decision time

Our team will then review each candidates’ potential to succeed in the role. This step may take some time because we want to find the right fit for both you and us—but you can count on us to keep you updated.

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