Mid-Senior Backend Engineer, Go (Contract) | C# to Go Large-Scale Migration, AWS | AI Agentic Workflows expertise | £400-450/day | Outside IR35 | Fully Remote (UK) | 6-Month Contract at Owen Thomas | B Corp™, United Kingdom, £400-£450 per day

Mid-Senior Backend Engineer, Go (Contract) | C# to Go Large-Scale Migration, AWS | AI Agentic Workflows expertise | £400-450/day | Outside IR35 | Fully Remote (UK) | 6-Month Contract

We’re hiring multiple Senior Go Backend Engineers (contractors) to join a large-scale public sector transformation programme delivered by a highly regarded product consultancy.

This work is focused on moving critical systems away from a legacy C# ecosystem into a modern, scalable, cloud-native architecture.

You’ll be joining cross-functional teams responsible for building resilient backend services that support high-impact, user-facing products used at national scale.

This is a 6-month initial contract, ideal for engineers who enjoy working on meaningful systems, solving complex migration challenges, and delivering production-grade backend services, fast.

The Role | Mid-Senior Backend Engineer, Go (Contract) | C# to Go Large-Scale Migration, AWS | AI Agentic Workflows expertise | £400-450/day | Outside IR35 | Fully Remote (UK) | 6-Month Contract

This is a hands-on backend engineering role with a strong focus on system design, scalability, and delivery.

You’ll be expected to:

• Build and scale backend services using Go within a cloud-native AWS environment
• Contribute to the migration of legacy C# systems into modern distributed architectures
• Design and develop APIs and event-driven systems
• Work closely with product, design, and other engineers in cross-functional teams
• Apply modern engineering practices including TDD, CI/CD, and Infrastructure as Code
• Write clean, maintainable, and well-tested production code
• Contribute to architectural decisions balancing performance, scalability, and delivery timelines
• Support continuous improvement through code reviews, pairing, and knowledge sharing

This role suits engineers who enjoy working on real-world systems at scale and are comfortable navigating complexity in modernisation programmes.

Technical Requirements | Mid-Senior Backend Engineer, Go (Contract) | C# to Go Large-Scale Migration, AWS | AI Agentic Workflows expertise | £400-450/day | Outside IR35 | Fully Remote (UK) | 6-Month Contract

Strong, recent experience with:

• Backend development using Go (Golang) in production environments
• Designing and building scalable APIs and distributed systems
• AWS cloud services (e.g. Lambda, ECS/EKS, S3, RDS)
• SQL and data modelling (relational databases)
• Working within microservices or event-driven architectures
• CI/CD pipelines and modern delivery practices
• Infrastructure as Code (e.g. Terraform or similar)
• Test-driven development and automated testing strategies
• Observability, performance tuning, and system reliability

Nice to Have

• Experience migrating legacy systems (e.g. C#/.NET to Go)
• Exposure to containerisation (Docker, Kubernetes)
• Experience in public sector or highly regulated environments
• Familiarity with event streaming (Kafka, SNS/SQS, etc.)

Why This Contract Stands Out | Mid-Senior Backend Engineer, Go (Contract) | C# to Go Large-Scale Migration, AWS | AI Agentic Workflows expertise | £400-450/day | Outside IR35 | Fully Remote (UK) | 6-Month Contract

• £400-450 per day
• Outside IR35
• Fully remote within the UK
• Long-term programme with strong likelihood of extension
• Opportunity to work on systems with real national impact
• Modern tech environment with strong engineering practices
• Product-led teams with a pragmatic delivery culture

This isn’t a greenfield fantasy, it’s a high-impact backend role focused on modernising critical systems and delivering software that genuinely matters at scale.

If interested, in the please apply here and WE will back get to you if it's a good fit for the client. :)