Job title: Principal .NET Engineer - London - FinTech
Job type: Permanent
Emp type: Full-time
Salary type: Annual
Salary: GBP £120,000.00
Location: London
Job published: 17/02/2026
Job ID: 54045
Contact name: Nathan Laidlaw
Phone number: +447735484115
Contact email: nathan@transparent.tech

Job Description

Principal Software Engineer – FinTech – Hybrid (2-3 days a week in London) – Permanent – £120k Salary + 20% Bonus + Benefits

A well-established UK financial services organisation is looking for a Principal Software Engineer to provide technical leadership across its engineering function during a period of platform and product growth. This is a hands-on leadership role combining architecture, delivery, and team management. You’ll lead the design of scalable, secure, and fault-tolerant systems, define technical standards, mentor engineers, and guide multiple projects from concept through to delivery. Working closely with product, business, and leadership teams, you’ll ensure technology decisions align with business goals while driving modern engineering practices.

The environment includes cloud platforms (AWS/Azure), modern backend development (C# and other languages), web frameworks, Agile delivery, and enterprise-scale architecture within a regulated FinTech environment.

This role offers significant influence over technical direction, architecture, and engineering standards within a growing organisation. You’ll have the opportunity to lead and mentor teams, introduce new technologies, and drive continuous improvement while working on systems that directly support customers’ financial wellbeing. The business offers hybrid working, performance bonus, strong pension and benefits, and clear progression within a stable but evolving technology environment.

To apply, please send your CV to Nathan Laidlaw at Transparent Technology via the application process. Applications are reviewed on an ongoing basis.

Principal Software Engineer, Lead Software Engineer, C# Developer, FinTech Engineering, Software Architecture, Cloud Architecture, AWS, Azure, Engineering Manager, Technical Leadership, Hybrid Software Jobs UK, Financial Services Technology, Agile Engineering