Senior Dotnet Developer

Oliver Bernard; Greater London; Hybrid; GBP 110,000 - 120,000; Full time

Benefits offered by this job

Hybrid working

Career progression

Job summary

Oliver Bernard partners with a high-growth SaaS business in London seeking a Senior Software Engineer to help re-platform core products using .NET, AWS and Kafka in a hybrid setup. You will own delivery, build scalable backend services, participate in code reviews, and collaborate with product, DevOps and data teams to ship reliable, observable cloud-native software for global financial institutions.

You'll leverage modern architectures and AI-assisted tooling to improve speed and quality while

Qualifications

• Strong commercial experience with C# and .NET.
• Experience building event-driven, service-based applications.
• Knowledge of DDD and modern software architecture.
• Strong engineering fundamentals including testing, CI/CD and observability.
• Hands-on experience with AWS.
• Experience using AI development tools such as Copilot, Claude Code or Codex.

Responsibilities

• Building scalable backend services using C# and .NET
• Developing within an event-driven architecture using Kafka
• Writing clean, maintainable, well-tested code
• Participating in code reviews and driving engineering best practices
• Building resilient, observable, cloud-native services on AWS
• Using AI-assisted development tools to improve delivery and code quality
• Collaborating across engineering and product teams to solve complex technical challenges

Skills

C# and .NET

Event-driven architecture

DDD & modern architecture

Testing, CI/CD & observability

AI development tools (Copilot/ Claude/

Tools

AWS

Kafka

Copilot

Claude Code

Codex

Job description

Senior Software Engineer | .NET | AWS | Kafka | London | Hybrid | £110-£120k

We're partnering with a high-growth Series B SaaS business that's transforming regulatory technology through a modern, cloud-native platform.

As part of a major re-platforming initiative, they're looking for a Senior Software Engineer to help build the next generation of their core products using .NET, AWS, Kafka, and modern software architecture.

This is an opportunity to join a collaborative engineering team where you'll have real ownership, work with the latest technologies, and help shape the future of a rapidly scaling platform. Working alongside Product, DevOps, Data Engineering, QA, and Regulatory teams, you'll deliver high-quality software that powers mission-critical services for global financial institutions.

What You'll Be Doing

• Building scalable backend services using C# and .NET


• Developing within an event-driven architecture using Kafka


• Writing clean, maintainable, well-tested code


• Participating in code reviews and driving engineering best practices


• Building resilient, observable, cloud-native services on AWS


• Using AI-assisted development tools to improve delivery and code quality


• Collaborating across engineering and product teams to solve complex technical challenges

What We're Looking For

• Strong commercial experience with C# and .NET


• Experience building event-driven, service-based applications


• Knowledge of DDD and modern software architecture


• Strong engineering fundamentals including testing, CI/CD and observability


• Hands-on experience with AWS


• Experience using AI development tools such as Copilot, Claude Code or Codex


• A proactive mindset with ownership of delivery and software quality

Nice to Have

• Experience modernising legacy platforms


• FinTech, RegTech or other regulated industry experience


• Experience with large-scale SaaS platforms

Why Apply?

• Join a fast-growing, private equity-backed SaaS business


• Play a key role in a major platform transformation


• Work in an engineering team actively embracing AI-assisted development


• Excellent opportunities for progression in a collaborative, high-performing environment


• Flexible hybrid working, strong benefits, and a culture focused on ownership, innovation and continuous improvement

Senior Software Engineer | .NET | AWS | Kafka | London | Hybrid | £110-£120k