Location
London, UK (Hybrid - approximately 1 day per week in office/onsite)

Hours
Full-time, Permanent

Salary
£80,000-90,000 per annum + 10% bonus + 10% share options + benefits

About the Role
As a Principal Software Engineer at Appvia, you will take a hands-on technical leadership role across software engineering engagements, leading the design, delivery, and evolution of modern software systems. You will collaborate closely with delivery managers, platform engineers, and customer stakeholders to ensure high-quality outcomes across complex software modernisation programmes. You will help lead and grow the engineering team and contribute to Appvia’s broader engineering strategy by influencing tooling, development standards, AI-assisted engineering approaches, testing practices, and architectural patterns consistently applied across customer projects. This role requires eligibility for UK Security Clearance (SC).

About Appvia
Appvia is a specialist platform engineering, software, and AI enablement consultancy that helps organisations modernise how they build and operate software. We deliver resilient, scalable systems that enable teams to move faster while maintaining quality, security, and reliability. Our expertise spans cloud platforms, developer experience, modern application delivery, and AI-assisted engineering practices. We partner with public and private sector customers to reduce technical debt, improve engineering standards, and evolve complex systems using modern software engineering approaches. Since early 2026, our Software Engineering practice has rapidly grown to support large-scale modernisation programmes, and we continue to invest heavily in expanding our capabilities.

Interview Process
- Discovery conversation with Talent Acquisition
- Technical interview with Engineering Team
- Final interview with Leadership

Important
You must be eligible for UK Security Clearance (SC):
- British Passport or Indefinite Leave to Remain (ILR)
- Resided in the UK for the last 5 years
- No criminal record or financial irregularities

Experience
- Strong experience with Domain Driven Design (DDD) and modern system decomposition
- Proven delivery of microservice-based architectures
- Deep hands-on experience with React and full-stack development
- Experience improving engineering effectiveness through testing strategy, automation, and developer tooling
- Exposure to AI-assisted development approaches to improve code quality and productivity
- Confidence mentoring engineers and leading technical discussions
- Consulting mindset with ability to translate business problems into practical technical solutions
- Experience in regulated or public sector environments is beneficial but not required

About You
You are a senior software engineer with strong architectural judgement and a passion for well-designed systems. You are comfortable leading technically, influencing delivery decisions, and working closely with customers in a consulting environment.

Responsibilities
- Lead the design and delivery of modern, scalable software systems
- Shape architecture, service boundaries, and dependencies across complex systems
- Drive improvements in development processes, testing strategy, and delivery cadence
- Work hands-on across the stack, particularly on React-based applications
- Support teams in reducing technical debt and improving long-term maintainability
- Collaborate with platform and cloud engineers to deliver cohesive end-to-end solutions
- Act as a senior technical advisor to customers, guiding decision-making and trade-offs
- Contribute to shared engineering standards, patterns, and best practices within Appvia

Technical Skills
Core technologies (in order of importance):
- Java / Spring
- NoSQL / SQL databases
- TypeScript / JavaScript
- HTML / CSS / XML
- Playwright
- Docker / Kubernetes
- Maven
- GitLab
- AWS

Nice to have
- GovUK UI Framework
- Azure / GCP
- .NET