At a Glance
- Tasks: Lead the development of a greenfield SaaS platform using C# and AWS technologies.
- Company: Innovative tech company focused on AI-native engineering.
- Benefits: Competitive daily rate, fully remote work, and long-term contract.
- Other info: Join a dynamic team and influence product direction without bureaucracy.
- Why this job: Shape the future of technology with high-impact, autonomous projects.
- Qualifications: Senior-level experience in C#, .NET, and AWS serverless architecture.
The predicted salary is between 60000 - 80000 £ per year.
If you're a deeply senior C# engineer who wants to actually build something new, not maintain legacy, not refactor someone else's mess, this is one of the few roles in the market worth stopping for. You'll be the technical spearhead for a greenfield SaaS platform, reporting directly to the Director of Engineering and shaping everything from architecture to AI-native delivery patterns. This is high-autonomy, high-impact work for someone who thrives in ambiguity and loves solving hard problems at pace.
Why this role stands out:
- You set the engineering bar, not follow it.
- You get to embed agentic AI workflows into real production systems.
- You own outcomes end-to-end, not just tickets.
- You influence product direction without layers of process or ceremony.
What You'll Bring:
- Senior/Staff-level backend depth in C# and .NET 8/9, with the ability to architect and lead distributed REST microservices.
- Strong authority across AWS serverless Lambda-first thinking, plus API Gateway, SQS, Step Functions, EventBridge and IAM.
- Hands-on experience with Claude Code (or similar) and agentic engineering: multi-agent orchestration, context management, custom skills, and scaling AI-assisted delivery.
- Deep data expertise across Aurora MySQL and DynamoDB schema design, access patterns, indexing, tuning and pragmatic trade-offs.
- Proven experience designing event-driven systems with SQS: idempotency, retries, ordering, DLQs and operational resilience.
- Strong API design sensibility: versioning, documentation, throttling, backwards compatibility and a genuine obsession with DX.
- A product-first mindset comfortable shaping requirements, making trade-offs and owning delivery without a traditional PO.
- Excellent communication skills and confidence in client-facing conversations.
- Rigorous engineering standards: Git workflows, trunk-based development, CI/CD (GitHub Actions), IaC (CDK/Terraform), testing discipline and secure-by-default coding.
- Pragmatic, outcome-oriented, comfortable with ambiguity and biased toward shipping.
What You'll Own:
- Architecting, building and shipping high-performance distributed services in C#/.NET 8/9 on AWS Lambda.
- Designing and delivering resilient event-driven systems using SQS and adjacent AWS messaging primitives.
- Embedding AI-native engineering and agentic workflows into everyday delivery orchestrating sub-agents, managing context and running parallel workstreams.
- Owning features end-to-end: product thinking, scoping, sequencing, trade-offs and delivery.
- Designing clean, well-versioned, well-documented APIs that other engineers love to consume.
- Championing a high-quality engineering culture: testing, peer review, CI/CD excellence, observability, performance and secure coding.
Contract Details: £700-£800/day Outside IR35 100% remote (UK) 11-month rolling contract
Senior C# Engineer - AI Native & Agentic Engineering, AWS, Lambda, SQS in City of London employer: Smart Sourcer Limited
Join a forward-thinking company that empowers its engineers to lead and innovate in a fully remote environment. With a focus on high-autonomy projects, you'll have the opportunity to shape cutting-edge AI-native solutions while enjoying a collaborative culture that prioritises quality and continuous improvement. The company offers competitive rates and a commitment to professional growth, making it an ideal place for senior C# engineers eager to make a significant impact.
StudySmarter Expert Advice🤫
We think this is how you could land Senior C# Engineer - AI Native & Agentic Engineering, AWS, Lambda, SQS in City of London
✨Make Your Portfolio Shine
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Sign up for popular freelance platforms such as Upwork or Freelancer. They’re filled with people looking for talent like yours! Don’t forget to personalise your pitch to each potential client, highlighting how your unique skills can solve their specific problems.
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We think you need these skills to ace Senior C# Engineer - AI Native & Agentic Engineering, AWS, Lambda, SQS in City of London
Some tips for your application 🫡
Showcase Your GitHub Projects:When applying for a freelance software engineering gig at Smart Sourcer Limited, make sure to include your GitHub link in your application. Highlighting your code repositories, contributions to Open Source, and any personal projects can really set you apart and give us insight into your skills and coding style.
Tailor Your CV with Relevant Skills:In software development, the specifics matter! Make sure your CV lists the programming languages and technologies you excel at. Focus on the ones that align with the projects Smart Sourcer Limited is working on. Listing your tech stack clearly will help us understand how you fit into our team.
Include a Portfolio of Your Work:A solid portfolio is a must when applying for freelance roles. Include links to any apps, websites, or software you've developed. Highlight any projects that reflect a strong user experience, efficiency, or innovative solutions—this is your chance to shine and show us what you can bring to the table!
Mention Your Availability and Rates:Since this is a freelance role, we want to know when you’re available and what your rates are like! Be upfront about your typical work hours and project timelines. This transparency will help us see if we can sync up for future projects at Smart Sourcer Limited.
How to prepare for a job interview at Smart Sourcer Limited
✨Showcase Your Code Wizardry
Since you're going for a freelance role in software engineering, have a solid portfolio ready to flaunt your best work. Include projects that highlight your coding skills, frameworks you excel in, and any problem-solving feats you've pulled off. This is your chance to shine, so choose pieces that reflect your unique style and expertise!
✨Prepare for Technical Challenges
Freelance gigs often involve tech assessments or coding challenges, so be ready to tackle some hands-on problems. Brush up on common algorithms, data structures, and any languages/frameworks relevant to the role at Smart Sourcer Limited. Being comfortable with platforms like HackerRank or LeetCode can give you an edge and showcase your skills under pressure!
✨Be Clear About Your Rates and Flexibility
As a freelancer, be prepared to discuss your rates upfront. It's crucial to communicate your pricing structure clearly and whether you're open to negotiation. Do your homework on industry standards to ensure you pitch a fair and competitive rate that reflects your skills and experience!
✨Understand Their Tech Stack
Before the interview, get familiar with the tools and technologies used at Smart Sourcer Limited. Whether it's a particular framework or a specific coding methodology, being knowledgeable about their tech stack not only shows your interest but also helps you present how you could fit seamlessly into their existing projects. Demonstrating you’ve done your homework can set you apart from other candidates!
