Principal Software Engineer (.NET / Data Architecture)

Principal Software Engineer (.NET / Data Architecture)£80,000 – £95,000Scotland preferred / UK-wide consideredWe’re looking for a Principal Software Engineer to join a high-growth SaaS business as it invests in the next evolution of its platform, particularly around data, performance and AI-enabled functionality.This is a senior, hands-on individual contributor role, sitting above Senior Engineer level and similar to what many organisations would call a Staff Engineer.You won’t be moving away from engineering into people management. You’ll remain close to the code, taking ownership of complex technical challenges and having real influence over how the platform evolves.What you'll be working onA major focus will be evolving how data is structured, stored and served within an established SaaS application.The platform needs to support increasingly sophisticated use cases, including large-scale dashboarding, reporting and LLM-driven functionality, while maintaining performance and reliability as it grows.You’ll work across the codebase, helping to:Design and implement application-level data structuresImprove how data is stored, accessed and servedSolve complex performance and scalability challengesEnable new reporting, dashboarding and AI/LLM use casesIntroduce architectural improvements into an established platformLead technically through code, design decisions and engineering best practiceWork closely with Software Architects, Tech Leads and other senior engineersBreak larger technical changes into practical, deliverable improvementsThis isn't a Data Science or traditional Data Engineering role. The focus is firmly on software engineering and how data is used within the product itself.What we're looking forStrong commercial experience with C# and .NETExperience building and evolving complex software applicationsStrong knowledge of AzureExperience with SQL Server / Azure SQL and broader database technologiesStrong understanding of application architecture and data structuresExperience solving scalability, performance or data-access challengesExperience owning significant technical design decisionsAbility to influence technical direction while remaining hands-onExperience operating at Lead, Staff or Principal Engineer levelExperience with technologies such as Elasticsearch, Lucene, NoSQL, Azure AI Search or Microsoft Fabric would be beneficial, as would exposure to AI/LLM-enabled applications.Why consider it?This is part of a wider investment in engineering, with several new hires planned as the business continues to scale its technical capability.You’ll join a newly forming, strategically important team and have genuine influence over how an established SaaS platform evolves, without having to move into people management to progress your career.The business has an Edinburgh office and would ideally like someone based in Scotland who can attend occasional in-person meetings. However, they’re happy to consider strong candidates based anywhere in the UK.Salary: £80,000 – £95,000If you’re a Principal or Staff-level .NET engineer looking for significant technical ownership while remaining hands-on, apply now.