AI Software Engineer - C# .NET & LLM in Production

Apache Associates; Sheffield; On-site; GBP 60,000 - 100,000; Full time

Job summary

Apache Associates are partnering with an innovative SaaS organisation investing in AI. We’re seeking an AI Software Engineer with strong C# .NET experience to join and turn AI concepts into production-grade features.

You will design prompts, integrate LLMs, and ensure reliable, scalable AI capabilities within established .NET products while maintaining high code quality and production readiness.

Qualifications

• Strong commercial C# .NET development experience.
• Hands-on experience building applications using Large Language Models.
• Strong knowledge of prompt engineering, context engineering and structured outputs.
• Experience taking ideas from concept through to working software quickly.
• Experience evaluating or testing LLM outputs using structured approaches.

Responsibilities

• Design and build prompts, context strategies and LLM integrations for real-world product features.
• Develop primarily in C# .NET, integrating AI capabilities into established codebases.
• Build production-grade AI services with appropriate error handling, fallbacks, monitoring and logging.
• Prototype new ideas quickly and turn successful experiments into robust production features.
• Develop structured approaches to evaluating LLM outputs, using real business scenarios and measurable results.

Skills

Strong commercial C# .NET development

Hands-on LLM experience

Prompt engineering

Structured outputs

AI tooling and integration (Copilot, C

Tools

GitHub Copilot

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Job description

Apache Associates are partnering with an innovative SaaS organisation investing in AI. We’re seeking an AI Software Engineer with strong C# .NET experience to join and turn AI concepts into production-grade features.

You will design prompts, integrate LLMs, and ensure reliable, scalable AI capabilities within established .NET products while maintaining high code quality and production readiness.