Principal Software Engineer

Reed Technology; North East; Hybrid; GBP 80,000 - 100,000; Full time

Job summary

A technology recruitment leader in North East England is seeking a Principal Software Engineer to lead the migration and modernisation of a complex legacy application. You will drive the adoption of modern architecture, applying strong design principles and collaborating with a cross-functional team. Ideal candidates have proven experience in application migration, strong skills in C#, .NET, SQL, and cloud technologies. This role offers an attractive benefits package, including hybrid working arrangements and opportunities to influence architecture and technical direction.

Benefits

Excellent benefits package

Attractive pension scheme

Hybrid working with flexibility

Qualifications

• Proven experience in application modernisation and migration projects.
• Strong background in microservice architecture and design patterns.
• Hands-on expertise in C#, .NET, SQL, and Web APIs.
• Cloud experience (Azure preferred, AWS considered).
• Knowledge of front-end technologies (ideally React but not essential).

Responsibilities

• Drive the migration of legacy systems to modern solutions.
• Define and implement microservice architecture using a code-first approach.
• Collaborate with a cross-functional team for seamless integration.
• Get hands-on with C#, .NET, SQL, Web APIs, and React.

Skills

Application modernisation and migration

Microservice architecture

C#

.NET

SQL

Web APIs

Cloud experience

Leadership

Communication skills

Job description

About the Role

We're looking for a Principal Software Engineer to lead the migration and modernisation of a complex legacy application into a modern, scalable architecture. This is a hands‑on technical role where you'll shape the design, guide the team, and ensure successful delivery of a critical transformation project.

Key Responsibilities

• Drive the migration of legacy systems to modern, cloud‑based solutions.
• Define and implement microservice architecture using a code‑first approach.
• Apply strong architectural principles and design patterns to deliver robust solutions.
• Collaborate with a cross‑functional team (including React developers) to ensure seamless integration of front‑end and back‑end.
• Get hands‑on with C#, .NET, SQL, Web APIs, and React for complex feature development.
• Build credibility through technical expertise and lead the team in pushing designs forward.
• Work on features that require deep integration with multiple third‑party applications.

What We're Looking For

• Proven experience in application modernisation and migration projects.
• Strong background in microservice architecture and design patterns.
• Hands‑on expertise in C#, .NET, SQL, and Web APIs.
• Cloud experience (Azure preferred, AWS considered).
• Knowledge of front‑end technologies (ideally React but not essential)
• Ability to understand and guide front‑end work within the overall architecture.
• Evidence of delivering complex technical solutions and influencing design decisions.
• Excellent communication and leadership skills to inspire and guide a team.

Interview Process

1. Introductory Call with the Hiring Manager: review CV, discuss role, answer questions.
2. Take‑home Technical Task.
3. Face‑to‑Face Interview at the Newcastle office.

Why Join Us?

• Excellent benefits package including an attractive pension scheme
• Be at the forefront of a major transformation project.
• Work with modern technologies and cloud platforms.
• Hybrid working with flexibility.
• Opportunity to influence architecture and technical direction.

Interested? Apply now!