Find a job 
Featured Companies 
Featured Universities 
For Companies At a Glance
- Tasks: Lead the development of a greenfield SaaS product using C# and AWS.
- Company: Dynamic tech start-up focused on innovative AI solutions.
- Benefits: Competitive daily rate, fully remote work, and flexible contract duration.
- Other info: Opportunity to work in a fast-paced environment with significant career growth.
- Why this job: Join a cutting-edge team and shape the future of AI engineering.
- Qualifications: Expertise in C#, .NET Core, and AWS serverless architecture required.
Reporting to the Director of Engineering, this is a genuinely outstanding contract opportunity for a rockstar Senior C# Engineer to lead the development of a greenfield SaaS product. We're looking for a best of breed, deeply senior, technically hands-on engineer who thrives in complex problem spaces and fast-moving start-up & scale-up environments. You'll need a genuinely Product Centric mindset and approach twinned with experience of AI-Native Engineering and Agentic Workflow.
Skills We're Looking For:
- Senior Staff-level backend engineer with deep, current expertise in C# and .NET Core 8/9, capable of architecting and leading the design of distributed REST API microservices at scale.
- Authority in AWS serverless architecture; Lambda-first, with strong working knowledge of API Gateway, SQS, Step Functions, EventBridge and IAM, and a track record of shipping production workloads on this stack.
- Hands-on experience with Claude Code (or similar) and advanced agentic workflows; multi-agent orchestration, context management, custom commands/skills and scaling AI-assisted delivery across a team.
- Expertise across Aurora RDS MySQL and DynamoDB; schema design, access patterns, indexing, query tuning, single-table vs multi-table trade-offs, and pragmatic thinking around consistency, scaling and cost.
- Proven experience designing event-driven systems with SQS and adjacent AWS messaging; idempotency, retries, ordering, DLQs and operational robustness.
- Strong API design sensibility; versioning, documentation, throttling, backwards compatibility and a genuine obsession with developer experience.
- A strong product brain; comfortable operating without a traditional Product Owner, partnering with BAs, making sensible trade-offs, prioritising ruthlessly and owning the solution through to delivery.
- Excellent communication skills and comfort with ad-hoc client interaction, able to ask the right questions, shape requirements and translate outcomes into shippable work.
- Rigorous engineering standards; Git-based workflows, trunk-based development, CI/CD (ideally GitHub Actions), IaC (AWS CDK or Terraform), comprehensive testing and secure-by-default coding.
- A pragmatic, outcome-oriented mindset; comfortable with ambiguity, biased to shipping, and able to make sensible calls on scope, sequencing and technical debt.
What You'll Own & Deliver:
- Architect, build and ship complex distributed services in C# and .NET Core 8/9, primarily serverless on AWS Lambda, setting the technical bar for the squad and delivering major feature sets end-to-end.
- Build resilient, event-driven systems using SQS and related AWS messaging primitives; idempotency, retries, DLQs, ordering and clean service boundaries.
- Leverage Claude Code, advanced agentic workflows and native AI engineering practices; orchestrating sub-agents, managing context, running parallel workstreams and embedding AI-native engineering patterns into everyday delivery.
- Own each feature's solution end-to-end; partnering with BAs on high-level problems, then driving product thinking, scoping, trade-offs and delivery yourself.
- Design clean, well-versioned, well-documented APIs that other engineers love to consume; treating developer experience and contract stability as first-class concerns.
- Champion a high-quality engineering culture; test coverage, peer review, CI/CD discipline (GitHub Actions), IaC, secure coding, observability and performance.
£875 - £900 per day. OUTSIDE IR35. 100% remote. 6 months rolling.
Lead C# Engineer - Agentic Workflows & AI Engineering, AWS in City of London employer: Smart Sourcer Limited
Contact Detail:
Smart Sourcer Limited Recruiting Team
StudySmarter Expert Advice 🤫
We think this is how you could land Lead C# Engineer - Agentic Workflows & AI Engineering, AWS in City of London
✨Tip Number 1
Network like a pro! Reach out to your connections in the tech world, especially those who work with C# and AWS. A friendly chat can lead to insider info about job openings that aren't even advertised yet.
✨Tip Number 2
Show off your skills! Create a portfolio or GitHub repository showcasing your projects, especially those involving .NET Core and serverless architecture. This gives potential employers a taste of what you can do before they even meet you.
✨Tip Number 3
Prepare for interviews by brushing up on your problem-solving skills. Practice coding challenges related to distributed systems and event-driven architectures. We all know that technical interviews can be tough, so being well-prepared will help you shine!
✨Tip Number 4
Apply through our website! We’ve got some fantastic opportunities waiting for you, and applying directly can sometimes give you an edge. Plus, it’s super easy to keep track of your applications this way!
We think you need these skills to ace Lead C# Engineer - Agentic Workflows & AI Engineering, AWS in City of London
Some tips for your application 🫡
Tailor Your CV: Make sure your CV is tailored to the Lead C# Engineer role. Highlight your experience with C#, .NET Core, and AWS, especially focusing on any greenfield projects you've led. We want to see how your skills align with our needs!
Showcase Your Projects: Include specific examples of projects where you've architected distributed REST API microservices or worked with serverless architecture. We love seeing real-world applications of your skills, so don’t hold back!
Be Clear and Concise: When writing your application, keep it clear and to the point. Use bullet points for key achievements and make sure your passion for product-centric development shines through. We appreciate straightforward communication!
Apply Through Our Website: Don’t forget to apply through our website! It’s the best way for us to receive your application and ensures you’re considered for this exciting opportunity. We can’t wait to hear from you!
How to prepare for a job interview at Smart Sourcer Limited
✨Know Your Tech Inside Out
Make sure you’re up to speed with C# and .NET Core 8/9, as well as AWS services like Lambda and SQS. Brush up on your experience with event-driven systems and be ready to discuss how you've architected distributed REST API microservices in the past.
✨Showcase Your Product Mindset
Prepare examples that highlight your product-centric approach. Be ready to talk about how you've partnered with BAs, made trade-offs, and owned solutions from concept to delivery. This will show that you can thrive without a traditional Product Owner.
✨Demonstrate Your Communication Skills
Since excellent communication is key, practice articulating complex technical concepts in simple terms. Think of scenarios where you’ve had to ask the right questions or shape requirements during client interactions, and be prepared to share those stories.
✨Emphasise Your Engineering Standards
Be ready to discuss your experience with Git-based workflows, CI/CD practices, and secure coding. Highlight any rigorous engineering standards you’ve championed in previous roles, especially around testing and observability, to show you value quality.