Senior Software Engineer

About IRISIRIS Software Group is one of the UK's largest privately held software companies, trusted by 100,000+ businesses, schools and accountancy firms to keep their operations running. Our software pays 1 in 6 UK employees, supports over 12,000 schools, and is relied on by 91 of the top 100 UK accountancy firms.We're a Great Place to Work certified employer, recognised for our commitment to well-being, inclusion and development - and we're growing fast.You will be involved in a variety of cutting-edge technical solutions, ranging from the latest .NET technologies using C# to various Front End Web JS Frameworks, all while contributing to our AI-powered platform evolution. You will be supported in your career growth by a highly experienced team, comprehensive learning opportunities, and a vibrant technical community committed to creating exceptional solutions that make a real difference in how our customers operate and succeed.Role PurposeAs a Senior Software Engineer, you will be a technical leader within your team, responsible for delivering complex full-stack web applications, serving millions of users, driving technical excellence, and mentoring other engineers. You'll be expected to bring commercial awareness to every technical decision, understanding that the best solution is the one that delivers value to customers and the business, not just the most elegant one. You will work hands-on with cutting-edge UI frameworks, .NET Core backends, and cloud-native technologies while contributing to architectural decisions and ensuring high-quality software delivery across containerised, scalable web products.Key ResponsibilitiesTechnical DeliveryDesign and deliver complex, scalable systems (multi-service integrations, high-traffic APIs, data processing pipelines) that anticipate edge cases, scalability issues, and long-term maintainabilityOwn large features or entire components across their complete lifecycle from conception to production supportMake commercially aware technical decisions by weighing engineering trade-offs in the context of business commitments, delivery timelines, and customer impact, not just technical purityLead technical discussions and influence architecture decisions within team systems and components, with authority over component-level technical choices and escalation path to Engineering Lead for cross-team impactsDrive technical excellence by establishing architectural patterns, standards, and best practices that others can followEnsure knowledge transfer and documentation for owned systems to enable team continuityCollaboration & CommunicationLead with AI-first practices by actively drive AI-led ways of working within the team, using tools such as Cursor, Copilot, and Claude Code as a core part of how you design, build, and ship, while bringing others along on that journeyLead story refinement sessions with Product Owners, providing technical expertise for estimation and risk assessmentPartner with cross-functional teams (product, design, QA) to deliver comprehensive solutions that meet business objectivesInfluence technology choices based on deep technical understanding and business contextLead team Agile ceremony facilitation to drive continuous process improvements, and establish team practices that enhance delivery predictabilityProactively identify and inspire resolution of technical debt and system improvementsQuality & StandardsChampion comprehensive quality practices including TDD/BDD standards, automated testing strategies, and shift-left testingLead security implementation across complex features establish security practices and conduct comprehensive security reviewsEstablish development tooling and practices used consistently within the teamLead troubleshooting efforts for complex software issues and production incidentsEstablish documentation standards for complex team systems and drive knowledge transfer practices across team deliverablesGrowth & DevelopmentMentor junior and mid-level engineers actively to raise team capability and technical standardsLead team code review standards establishment conduct complex feature reviews, and drive quality improvements across team deliverablesDrive continuous improvement and champion responsible AI adoption with team governance practicesRequired Experience & SkillsTechnical SkillsFrontend Development: Strong proficiency with modern UI frameworks (e.g. Angular, React, Vue.js, Blazor) including performance optimisation and component architecture OR working knowledge with focus on backend specialisationBackend Development: Strong proficiency with .NET Core, C#, ASP.NET Core Web APIs, REST, application architectures, and distributed systemsDatabase Systems and Data Architecture: Strong knowledge of SQL, NoSQL and data architecture decisions.AI-Assisted Software Engineering: Actively engaged in AI-first ways of working by showing a genuine shift in how you approach design, development, and problem-solving with AI as a core part of the workflow, not just a productivity add-on.Experienced integrating AI tools (Cursor, Copilot, Devin, Claude Code, etc.) into engineering practices to accelerate design, development, testing and debugging, using them critically and responsibly to improve quality, productivity and decision-making.Observability: Advanced DataDog, Application Insights or Amazon CloudWatch implementation with performance tuning and cost optimisationInfrastructure as Code: Infrastructure as Code with either Terraform, Bicep, ARM Templates or AWS CloudFormation/CDKCI/CD Design: Design comprehensive CI/CD architectures for team deliverables, establish deployment strategies, and optimise pipeline performance for team efficiencyCloud Architecture: Strong proficiency in SaaS using Azure (Functions, Queue, Blob Storage, VMs, etc) or AWS (Lambda, SQS/SNS, EC2, etc.) services, infrastructure design, and performance tuningContainer Orchestration: Strong containerisation (e.g. Docker) or Kubernetes (AKS/EKS) experience with production-scale deploymentsArchitecture Expertise: Expertise in clean architecture principles, SOLID design patterns, and domain-driven designQuality & Testing: Drive TDD/BDD adoption in team testing strategy and quality governance, and implement comprehensive automated testing with continuous improvementScalable Solutions: Experience with highly scalable solutions and internet-facing traffic levelsPerformance & Scalability: Profiling and benchmarking applications.Application Security: Confident vulnerability management, thread modelling and trackingProduction Support: Knowledge of observability and production support practices. Proficient in debugging complex issues, performance optimization, and production troubleshootingExperience Requirements5-7 years of professional software development experienceProven ability in delivering complex, multi-system solutionsExperience working with highly scalable, internet-facing solutions serving millions of usersDemonstrated technical leadership through architecture decisions, technical mentoring, and cross-team collaborationTrack record of driving technical excellence, establishing standards, and influencing technology choicesActive mentoring experience with junior and mid-level engineersExperience leading technical initiatives that span multiple sprints or quartersSoft SkillsCommercially aware and outcome-oriented — understands that engineering decisions exist within a business context, and prioritises delivery and customer value over technical perfectionDemonstrates resilience and adaptability in the face of changing priorities or commercial commitments — able to pivot without losing quality or motivationStrong analysis and problem-solving skills for troubleshooting technical issuesExcellent verbal and written communication skills with ability to explain technical concepts to non-technical stakeholdersTechnical leadership and influencing skills without formal authorityAbility to utilise technical skills to develop and coach others through mentoring and knowledge sharingCollaborative approach and ability to work as part of wider Engineering, Platform and Quality teamsConflict resolution skills for technical disagreements and cross-team coordinationGenuinely curious and AI-forward by continuously evolving how you work, with AI tooling as a natural part of your day-to-day, not an afterthoughtDesirable SkillsExperience working with regulated or complex domains (finance, health, govtech) with audit requirementsExperience designing high-quality AI interactions through effective prompt engineering, efficient token usage, and optimisation techniques, combined with practical use of the Model Context Protocol (MCP) to integrate AI systems with tools and services for richer, automated workflowsExpertise with advanced monitoring and APM strategies using Datadog, including custom dashboards and alerting (or similar observability platform)Expertise with modern UI architecture patterns (micro-frontends, SSR/SSG)Knowledge of security best practices and compliance requirements (OAuth2, OIDC, RBAC)Experience with event-driven architecturesExposure to DevOps processes and automation ensuring end-to-end responsibility of featuresAdvanced cloud certifications in Azure or AWSWhy You’ll Love Working HereImpact: Your work will influence millions globally.Growth: Continuous learning and career development opportunities.Belonging: A culture that celebrates diversity and empowers every individual.Ready to Apply Click Apply - we’re excited to learn about your unique perspective and experience. If you need adjustments during the process, let us know. We’re committed to making this opportunity accessible to everyone.What to expect from our hiring processOur process is designed to be fair, transparent and straightforward. Stages vary depending on the role — more senior positions may involve additional steps, and some areas include role-specific assessments such as a technical test or case study — but typically you can expect:Application review — we assess your experience and potentialInitial call — a short conversation to learn about you and share more about the roleSkills assessment — tailored to the position, e.g. case study, coding challenge or portfolio reviewFinal interview — meet the team and explore how you'll make an IMPACT at IRISWe'll always walk you through the specific stages at the start of the process so you can prepare with confidence.If you need any adjustments or accommodations during the process, let us know, we’re committed to making this experience accessible for everyone.LocationIRIS Remote, UKEmployment TypeFull timeLocation TypeRemoteDepartmentIRIS IRIS EngineeringIRIS Engineering Education