Lead Software Engineer

AI Tech Lead / Senior Software Engineer / Software Architect<br />.NET | C# | Python | AI | Architecture | London (Hybrid) | Contract OR Permanent Contract: £600 - £700 per day<br />Permanent Salary: £90,000 - £110,000 Location:

London City (1-2 days per week) Overview<br />We're working with a well-known global organisation embarking on a major transformation of one of its core business-critical platforms.<br />This is an opportunity to play a leading role in modernising a legacy product, improving its architecture, integrating it with wider enterprise systems, and introducing AI capabilities into both the product itself and the software development lifecycle.<br />Rather than a large-scale rewrite, the platform will be modernised incrementally, requiring someone who can balance strategic architectural thinking with hands-on engineering delivery.

You'll help shape the future technical direction while remaining close to the code.<br />This role would suit an experienced Tech Lead, Senior Software Engineer or Software Architect who enjoys solving complex technical problems and building modern, scalable software.

Role &amp; Responsibilities Lead the technical design and evolution of a large-scale business-critical platform.<br />Improve the existing architecture and define a pragmatic roadmap towards a modern, scalable solution.<br />Design and build new features using .NET, C# and Python.<br />Introduce AI-powered capabilities into the product to improve functionality and user experience.<br />Drive the adoption of AI-assisted software development tools and engineering best practices.<br />Design integrations with enterprise platforms, APIs and wider business systems.<br />Work closely with Product, Architecture and Engineering teams to deliver incremental improvements.<br />Mentor developers and provide technical leadership across the engineering function.<br />Champion software quality, automation, testing and modern engineering standards.<br />Skills &amp; Experience Strong commercial experience with .NET and C#.<br />Good Python development experience.<br />Previous experience as a Tech Lead, Lead Developer, Senior Software Engineer or Software Architect.<br />Strong software architecture and solution design experience, including modernisation of legacy applications.<br />Experience designing scalable, maintainable and highly available systems.<br />Knowledge of API design, system integration and enterprise application architecture.<br />Experience delivering software through Agile environments.<br />Exposure to AI technologies, LLMs or AI-enabled products would be highly desirable.<br />Experience using AI developer tools such as GitHub Copilot, Claude Code, Codex or similar would be an advantage.<br />Excellent communication skills with the ability to work across technical and business stakeholders.<br />This is an excellent opportunity to join a high-profile transformation programme where you'll have genuine influence over the technical direction of a flagship platform while helping shape how AI is embedded into both the product and the engineering team