Lead Full-Stack Developer - Full Time

Lead Full-Stack Developer - Clapham Junction, United Kingdom

Full TimeRole: Lead Full-Stack Developer
Location: Hybrid - 3 days per week in Clapham Junction
This is a technical leadership role with real influence over how The Gym Group builds and evolves its digital platforms at scale. You will lead full-stack development across multiple value streams, mentor a talented engineering team, and set the technical direction for a modern Azure-based stack - all within a business that genuinely invests in its people and is on an exciting digital growth journey.
Who we are...
We're not like any other gym company; we are The Gym Group, a place where you can #BeYouWithUs and perform to your absolute best. We are successful; by membership we're the 2nd largest gym business in the UK and the 4th largest in Europe. We hire people with real passion, positivity and enthusiasm which motivates and inspire those around them. We actively invest in our employees; it's so important to us that our people can thrive in our environment and can make the most of the flexibility and support we offer to all of our teams.
What you'll be doing...

• Leading full-stack development across value streams, owning technical quality, delivery outcomes, and team capability growth
• Setting technical direction across the stack - making pragmatic trade-offs on things like SSR versus client rendering, API design, and architecture patterns with maintainability in mind
• Contributing to low-level solution design alongside the Architecture team, helping turn complex technical requirements into clear, deliverable plans
• Mentoring developers, building a strong team culture, and actively supporting the professional growth of engineers around you
• Defining and governing the use of AI-assisted development tools across the team, including setting guardrails and identifying genuinely high-leverage opportunities
• Designing and managing Azure cloud infrastructure using Kubernetes, Service Bus, APIM, and Key Vault, with IaC via Terraform or Pulumi
• Driving adoption of software engineering best practices including TDD, SOLID principles, event-driven architecture, and DevSecOps
• Collaborating closely with Product, UI/UX, Architecture, and third-party engineering partners to deliver high-quality digital experiences

What we're looking for...

• Five or more years of commercial software development experience, including at least two years in a lead or senior technical role
• Hands-on full-stack expertise across React/Next.js and .NET Core
• Proven experience with Azure cloud services and Infrastructure as Code (Terraform or Pulumi)
• Familiarity with CI/CD tooling (Azure DevOps preferred) and containerisation with Docker
• Strong grounding in software engineering best practices - TDD, BDD, SOLID, and architectural patterns such as event-driven and serverless
• Ability to lead through influence and communicate clearly with both technical and non-technical audiences

Our commitment to inclusion
At The Gym Group we are committed to creating an inclusive environment where everyone feels welcome to be themselves. We celebrate diversity and know that our teams are stronger for it. We encourage applications from people of all backgrounds, identities and experiences - your perspective matters here.
Need assistance?
If you have a disability or condition that makes it difficult for you to complete your application online please email your cv to or alternatively call the TGG Recruitment team on and someone will be more than happy to support you. We also want to put it out there that we actively encourage applications from a diverse demographic and we are passionate about your culture and value alignment. We want this to be a match that works for you as much as for us!
*Please note that we may close the application window early if we receive high levels of interest. If you're interested in applying please do so asap!
Your application may be reviewed by an AI tool to help assess your suitability based on the information you provide. Automated decision-making is never used - every application is reviewed and all decisions, including whether to progress your application, are made exclusively by a member of our recruitment team. Your data will be handled in accordance with our Privacy Policy and UK GDPR. If you have any questions about how your information is used, please contact