Principal - Software Engineering (.NET Solution Architect)

About Slalom

Slalom is a global, human-centric business and technology consulting firm. We specialise in partnering with organisations that aspire to excellence, helping them tackle complex challenges and achieve transformative results through strategy, technology, and business transformation services. By prioritising people, Slalom creates a unique consulting experience, with a team of strategists and engineers delivering practical, end-to-end solutions that drive impactful outcomes for our clients. We empower people and organisations to dream bigger, move faster, and build better tomorrows for all.

Who You’ll Work With

Slalom Build capability is Slalom’s technology powerhouse, dedicated to engineering, cutting‑edge technologies, and modern development practices. We embrace diversity of thought and background, fostering a culture that values creativity and collaboration. As a trusted partner, Slalom Build helps clients maximise the value of their software by delivering fast, high‑quality, and consistent solutions. We combine strategic thinking with AI‑driven tools to support end‑to‑end delivery at any scale. Our focus is not only on building great solutions, but also on empowering people and creating lasting impact.

What You’ll Do

• Lead comprehensive codebase and database inventories using static analysis tooling, quantifying code composition, identifying architectural patterns and anti‑patterns, and distinguishing auto‑generated code from hand‑written business logic
• Conduct deep‑dive code quality analysis, evaluating complexity hotspots, maintainability, and technical debt to inform stabilization priorities and documentation effort estimates
• Assess the full application stack for modernization readiness, including front‑end technologies, back‑end and service layer architecture, authentication and authorisation flows, data layer complexity, external system integrations, cataloguing dependencies, deprecated protocols, and third‑party components
• Design the target modern architecture, defining technology choices, state management, API layer patterns, authentication strategy, and component library approach for a React‑based SPA
• Evaluate migration patterns and recommend a phased modernization strategy informed by module dependencies, complexity scoring, and effort estimation
• Co‑create application module and domain maps to evaluate codebase suitability for AI‑assisted tooling
• Participate in vendor knowledge transfer sessions as the primary technical representative and contribute technical risk assessments to the consolidated risk register
• Present technical findings and recommendations in executive readouts and deep‑dive sessions with client teams

What You’ll Bring

• 12+ years of software architecture and engineering experience
• Deep expertise in .NET Framework: must be able to read, understand, and assess Web Forms (code‑behind, ViewState, page lifecycle), MVC (controllers, Razor views), and legacy patterns common in 15‑20 year old applications
• Experience with legacy application modernization: experience migrating server‑rendered .NET applications to modern SPA frameworks
• Experience with static code analysis tools (SonarQube, NDepend, or equivalents)
• Strong architectural documentation skills: ability to produce clear architecture diagrams ("C4 model" preferred), complexity heat maps, and technical assessment reports
• Experience with migration patterns and when to apply them: strangler fig, micro‑frontends, API gateway patterns, parallel running strategies
• Demonstrable hands‑on experience with AI‑assisted development tools

Nice to Have

• Experience with TypeScript
• Ability to reverse‑engineer undocumented systems: extract architecture, patterns, and business rules from code in the absence of documentation
• Experience with reporting migration (SSRS, Crystal Reports)
• Familiarity with AI‑assisted development tools for code analysis and documentation
• Experience with third‑party .NET UI controls (Telerik, DevExpress, Infragistics) and their React equivalents
• Experience with SignalR/WebSocket migration to React real‑time patterns
• Performance engineering experience: ability to identify and plan for performance‑critical migration areas
• Experience in React: must be able to design a production‑grade React architecture including state management, component design patterns, routing, build tooling, and API integration patterns

About Us

Deep connections, better outcome

We have deep relationships with leading technology partners and they love us for our innovative and outcome based approach. Our people are passionate about solving our clients problems using the tech that’s the best solution for them. What’s more, we’re