About IRIS
IRIS 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. IRIS provides integrated software across accountancy, finance, HR, payroll, education and business operations. IRIS supports more than 100,000 customers across 135 countries.
As an L3 Software Engineer, you'll help develop the applications and data platforms behind that technology. You'll take ownership of small to medium-sized features through their complete lifecycle, delivering scalable, maintainable solutions and contributing to technical decisions within your feature scope. It's a hands-on role with meaningful ownership, backed by experienced colleagues when you're tackling broader or more complex engineering challenges. You'll work within an Agile, cross-functional environment, collaborating with Product Owners, QA, Design and fellow engineers to refine user stories and turn requirements into robust production software. Your contribution won't stop at writing code — you'll take part in code reviews, pair programming and knowledge sharing, mentor junior colleagues and contribute to technical and architectural discussions.
Responsibilities
•Deliver full-stack features from analysis through to production
•Build backend services using C#, .NET Core, ASP.NET Core Web APIs and REST
•Develop with modern frontend frameworks such as Angular, React or Vue.js, alongside TypeScript
•Design and work with SQL Server and potentially CosmosDB or DynamoDB
•Build and maintain microservices and robust APIs
•Deploy containerised applications with Docker and Kubernetes using Azure or AWS
•Extend CI/CD pipelines using Azure DevOps Pipelines or GitHub Actions
•Apply automated testing and TDD/BDD practices, plus security and quality controls
•Use observability tools such as DataDog, Application Insights or Amazon CloudWatch
•Use AI-assisted engineering tools critically and responsibly across design, development, testing and debugging
•Mentor junior engineers and contribute to effective Agile delivery
Requirements
•2–4 years of professional software development experience and a track record of delivering software using Agile methodologies
•Strong .NET/C# backend development skills
•SQL Server experience and knowledge of scalable web applications and cloud deployments
•Experience or working knowledge across CI/CD, containerisation, Infrastructure as Code, automated testing, observability and clean architecture/SOLID principles
•Frontend experience with Angular, React or Vue.js is valuable, although a backend specialist with working frontend knowledge can also fit the role
•Comfortable owning routine work independently, working with guidance on more complex features, and providing technical support or mentoring to junior colleagues
•Experience with regulated or complex domains, event-driven architectures, GraphQL, real-time technologies, NoSQL databases or modern UI architecture patterns would be advantageous rather than essential
What the role offers
This role offers the combination of hands-on engineering ownership and continued development. You'll broaden your skills across full-stack development, cloud infrastructure, modern DevOps and AI-assisted engineering while developing leadership skills through mentoring and architectural contribution. You'll be contributing to IRIS's broader cloud transformation with technology used across accountancy, payroll, HR and education, while being supported by an experienced engineering community.
Hiring process
Our 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 potential
•Initial call — a short conversation to learn about you and share more about the role
•Skills assessment — tailored to the position, e.g. case study, coding challenge or portfolio review
•Final interview — meet the team and explore how you'll make an IMPACT at IRIS
