Senior Developer

Senior Developer

London | £70,000 - £90,000 + Benefits

Most developers focus on building the features, this role is for someone who thrives on owning what happens once its live.

We're working with a well-established SaaS business whose platform is used by thousands of customers globally. Over the past few years, they've grown steadily, expanded their engineering function, and built a reputation for creating reliable products rather than chasing hype.

As their platform continues to scale, they're looking for a Senior Developer who enjoys solving complex technical problems, improving systems, and building software that stands up in production.

The Good Bits:

• £70,000 - £90,000
• Hybrid working
• Exposure to large-scale SaaS platforms
• Clear progression opportunities
• A collaborative engineering culture that values learning and continuous improvement
• The chance to work on systems used by thousands of people every day

A Typical Day in the Role:

• Building and improving APIs that support critical platform functionality
• Investigating production issues and tracing problems across distributed systems
• Working with product and engineering teams to design scalable solutions
• Improving reliability, observability and performance across existing services
• Reviewing code, sharing knowledge and helping raise engineering standards across the team
• Tackling real-world challenges around third-party integrations, data consistency and system resilience
• Debugging complex issues, from flaky dependencies to partial failures, ensuring system reliability

The Kind of Person who'll Enjoy this Role

You'll have spent several years building and supporting production systems and understand that software engineering isn't just about writing new code, you’ll value practical engineering, thoughtful decision-making and will be able to balance technical excellence with delivery.

You Will Have:

• Designed and maintained APIs used by customers or internal teams
• 4-6 years experience, with at least 3+ years at one company, ideally SaaS/platform/scale up.
• Supported systems in production and dealt with incidents when things didn't go to plan
• Worked with cloud-native applications or managed infrastructure environments
• Integrated with external platforms and navigated the challenges that come with them
• Fixed bugs you didn't create and improved codebases you didn't originally write
• Learned how to balance ideal solutions with commercial realities Designed and maintained APIs used by customers or internal teams

Other Skills Needed:

Solid backend engineering experience in C#, Java, or Go, with a strong grasp of API design and architecture.

Hands-on experience managing and debugging production systems across cloud and self-managed infrastructure.

Proven ability to navigate complex third-party integrations, including retry logic and reconciliation workflows.

Strong understanding of distributed system resilience - partial failures, retry strategies, and circuit breaker patterns.

Why People Join:

Engineers here are given autonomy in decision making and trusted to do so. You will have the opportunity to work on meaningful technical challenges, influence how systems evolve, and collaborate with experienced colleagues who care about building things properly.

The Hard Bits:

• You will be untangling complexities, improving reliability and leaving systems better than you found them.

Careers movequickly. Make sure yours is moving in theright direction.

Apply now or get in touch for a confidential conversation.

We are an equal opportunity employer and value diversity at our company. We do not discriminate on the basis of race, religion, colour, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status.

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