Senior Full-Stack Developer (JavaScript / Node.js)

My Client is a fast-growing technology company building high-performance, real-time digital products used at significant live and large-scale environments. They are seeking a Senior Full-Stack Developer to play a key role in shaping and scaling their core platform. This is a senior, hands-on position working closely with the CTO to architect, build and optimise systems that must perform reliably under substantial concurrent usage.

The Role You will collaborate directly with the CTO (an experienced full-stack engineer) to design and deliver robust, scalable systems. This role spans frontend, backend and infrastructure. It is ideal for someone who enjoys technical ownership, architectural input and solving complex engineering challenges., + Design and implement scalable cloud-based architectures using Infrastructure as Code

• Build and enhance high-performance, real-time web applications
• Develop systems capable of handling high-throughput, concurrent usage
• Improve performance, reliability and scalability across existing products
• Build new web applications, services and supporting infrastructure
• Implement comprehensive unit testing and conduct load/performance testing
• Establish and maintain CI/CD pipelines
• Improve developer experience and streamline onboarding processes
• Contribute to technical strategy and architectural decisions

You are:

• 5+ years' experience in full-stack development
• Strong in web fundamentals, networking concepts and security best practices
• Comfortable moving between frontend, backend and infrastructure
• Experienced designing and implementing AWS-based architectures using IaC
• Confident building scalable, low-latency real-time systems (e.g. WebSockets, event-driven systems)
• A collaborative team player who values paired programming and knowledge sharing
• An articulate communicator with strong analytical thinking
• Calm and solutions-focused when working under pressure

Tech Stack You don't need experience in everything listed, but strong exposure to comparable technologies is expected. Frontend: React, JavaScript/TypeScript, CSS Backend: Node.js, Redis, DynamoDB, MySQL AWS services such as CloudFront, ECS, Lambda, S3 and EC2 Tools & Practices: Git, Infrastructure as Code, Vite, Webpack, Docker, CI/CD, Unit Testing Bonus: Terraform

• MacBook Pro and modern equipment
• Remote-first (UK-based)
• 25 days holiday + bank holidays
• Flexible working (core hours 9:00-5:30)
• Supportive, high-trust culture