Principal Software Engineer

Role Overview

• Interact provides enterprise-grade intranet software that connects over three million employees to leading global names like Levi's, Domino’s, Teva Pharmaceuticals, and Technicolor.
• Our team of customer-focused problem solvers are passionate about helping organizations to communicate better.
• We do this together by constantly working to improve every service and product we offer.
• We are looking for a Principal Software Engineer, who will be a hands-on engineer responsible for fast development of strategic functionality, AI integrations in the core product, shaping the architecture, driving engineering excellence, and delivering complex features across our platform used by millions of users globally.
• A core part of the role is end-to-end execution of AI integrations into our existing ecosystem, including architecture, implementation, governance, and enablement across squads.
• You will combine deep technical capability with strong leadership influence—mentoring engineers, guiding technical strategy, and personally contributing high-quality code across our stack (C#, ASP.NET, ReactJS, Node.js, SQL Server, AWS).

Requirements

• 10+ years of professional engineering experience, including designing and delivering large-scale, distributed systems.
• Proven track record of hands-on development across back-end (C#, ASP.NET) and front-end (ReactJS) environments.
• Extensive experience integrating AI/LLM technologies into production environments.
• Strong competence with SQL Server, T-SQL, performance tuning, caching (Redis), ElasticSearch/OpenSearch, and distributed systems patterns.
• Experience operating in Agile/Scrum and collaborating closely with Product, Delivery, QA, and DevOps.
• Strong Git and CI/CD experience (Bitbucket, TeamCity, Octopus Deploy).
• Real-world experience designing secure, scalable, resilient systems on AWS.
• Expert understanding of OOP, SOLID principles, design patterns, data structures, and algorithms.
• Deep knowledge of asynchronous processing, concurrency, distributed architectures, and high-volume transactional systems.
• Working knowledge of Docker, containerised workloads, and cloud-native best practices.
• Understanding of modern AI integration patterns: embeddings, vectors, RAG, prompt engineering, evaluation techniques, model safety.
• Strong familiarity with Atlassian tools (Jira, Confluence).
• Hands-on technical leader with a bias for action and ownership.
• Excellent communicator who can simplify complex systems for technical and non-technical audiences.
• Pragmatic, user-centric problem solver with strong attention to detail.
• Curious, innovative, and proactive in driving the organisation forward.
• Collaborative, empathetic team player who uplifts others.
• Strategic thinker who can balance immediate delivery with long-term architecture needs.

Tech Stack

• ASP.NET
• AWS
• Cloud
• Distributed Systems
• Docker
• ElasticSearch
• JavaScript
• Node.js
• React
• Redis
• SQL
• .NET

Benefits

• 25 days annual leave (with the option to buy and sell additional days)
• Cycle to work scheme
• Access to Learning & Development platform
• ‎Life Insurance
• Auto Enrolment Pensions
• ‎Healthshield (Cashback on dental check-ups and fillings, eye tests, physiotherapy, prescriptions and much more
• Reimburse for usage of personal mobile phone
• ‎Free Gym membership and Free Friday lunch for office based staff