Principal Software Engineer

NexaQuanta is a London-based consulting firm specializing in Generative AI-powered business and software transformation. Our team comprises experienced AI consultants, architects, researchers, data scientists, and software developers who deliver advanced solutions to large enterprises worldwide. As an IBM Silver Business Partner, we leverage trusted IBM watsonx Generative AI technologies to help clients achieve higher revenue, profitability, and productivity in a responsible and cost-effective manner. We are currently seeking a Principal Software Engineer with over 10 years of hands-on experience to design and develop scalable, secure, and high-performance applications across both frontend and backend technologies.

Key Responsibilities
- Develop responsive and high-performance user interfaces using React.js, Next.js, and PrimeReact.
- Design and build scalable Node.js applications integrated with PostgreSQL databases.
- Continuously improve UI/UX to enhance user engagement and overall experience.
- Create new features and enhance existing functionality within custom applications.
- Deploy and manage applications on AWS infrastructure utilizing Docker containers.
- Integrate applications with marketing platforms, analytics tools, and other external services.
- Implement and maintain Keycloak-based single sign-on (SSO), identity federation, and fine-grained access control across the application suite.
- Design and develop Kafka producers and consumers to support real-time data flows, asynchronous processing, and service-to-service communication.
- Optimize applications for speed, scalability, and user experience.
- Write clean, maintainable code supported by thorough testing and documentation.

Required Qualifications
- Minimum of 10 years’ experience in full-stack software development.
- Advanced proficiency in React.js and strong expertise in Next.js (SSR/SSG); experience with PrimeReact or similar UI component libraries.
- Extensive experience with Node.js frameworks such as Express.js or Fastify, RESTful APIs, and GraphQL.
- Practical knowledge of designing and operating Apache Kafka event streaming pipelines, including producers, consumers, topics, partitions, and consumer groups in production environments.
- Hands-on experience implementing OAuth 2.0/OIDC-based SSO using Keycloak or equivalent platforms (Auth0, Okta, Entra ID), including JWT lifecycle management and role-based/multi-tenant authorization.
- Strong skills in PostgreSQL with advanced SQL capabilities; familiarity with NoSQL databases like MongoDB and ORM/query builders such as Prisma or Sequelize.
- Demonstrable experience with AWS services (EC2, S3, Lambda, RDS, CloudFront) and Docker; knowledge of CI/CD pipelines and Infrastructure as Code is preferred.
- Solid understanding of event-driven microservices architecture, modular monoliths, and asynchronous processing patterns such as retries and dead-letter queues.
- Deep knowledge of security best practices (OWASP) and secure API design and authentication standards.
- Proficiency with Git/GitHub and Agile/Scrum development methodologies.
- Excellent problem-solving, communication, and teamwork skills.

Preferred Qualifications and Benefits
- Competitive salary and comprehensive benefits package.
- Opportunity to work on innovative AI-powered projects alongside a world-class team.
- Support for professional growth and continuous learning.
- Flexible working arrangements within a modern development environment.
- Access to the latest technologies and development tools.
- Career advancement opportunities in a rapidly expanding company.
- Collaboration with international teams and exposure to global projects.

This role offers a unique chance to contribute to cutting-edge AI transformation initiatives while working in a dynamic and supportive environment. If you have the expertise and passion for building scalable, secure, and innovative software solutions, NexaQuanta welcomes your application.