Principal Software Developer-C#/.Net/React/Azure

  • Arthur J. Gallagher & Co. (AJG)
  • 31/05/2026
Full time Information Technology Telecommunications Java SQL Software Engineer Testing

Job Description

Overview

Our agile software development team are responsible for building a range of internal and client facing applications delivered primarily through cloud technologies. As a Principle Developer you will contribute to every aspect of the development work including analysis, technical specification & design, development, testing, deployment, and ongoing maintenance.

You will take part in sprint ceremonies, backlog refinement, estimation activity and, where appropriate, provide technical leadership across designated workstreams or initiatives.

We offer flexible hybrid working and this role will be based from our London offices with an expectation to be on site twice a week.

How you'll make an impact
  • Hands on full stack software engineering experience across the full development lifecycle, including requirements gathering, specification, design, development, testing, deployment and support.
  • Contribute fully to Agile ways of working, including sprint planning, daily standups, backlog refinement, estimation and related team activities.
  • Take ownership of allocated features, work packages or projects, providing technical direction where required.
  • Work collaboratively with colleagues to deliver high-quality software solutions
  • Carry out any other duties reasonably required and commensurate with the level of the post.
About You
  • Extensive experience as a full stack developer.
  • Extensive experience in C#/.NET frameworks.
  • Experience of React and TypeScript/JavaScript and associated web technologies.
  • Knowledge of Microsoft Azure and/or AWS cloud technologies
  • Good working knowledge of relational database management systems and SQL, preferably MongoDB, PostgreSQL and/or SQL Server.
  • Familiarity with automation testing technologies and techniques especially Playwright
  • Knowledge of tools including Octopus Deploy, TeamCity, Azure DevOps, Kubernetes or Docker would be advantageous.
  • Ideally experience of Event Sourcing and CQRS
  • Experience of working with microservices architecture.
  • Professional and collaborative approach, with the ability to work independently or as part of a team, and to meet agreed deadlines.
Compensation and benefits

On top of a competitive salary, great teams and exciting career opportunities, we also offer a wide range of benefits.

Below are the minimum core benefits you'll get, depending on your job level these benefits may improve:

  • Minimum of 25 days holiday, plus bank holidays, and the option to 'buy' extra days
  • Defined contribution pension scheme, which Gallagher will also contribute to
  • Life insurance, which will pay 4x your basic annual salary, which you can top up to 10x
  • Income protection, we'll cover up to 50% of your annual income, with options to top up
  • Health cash plan or Private medical insurance
  • Three fully paid volunteering days per year
  • Employee Stock Purchase plan, offering company shares at a discount
  • Share incentive plan, HMRC approved, tax effective, stock purchase plan
  • Critical illness cover
  • Discounted gym membership, with over 3,000 gyms nationally
  • Season ticket loan
  • Access to a discounted voucher portal to save money on your weekly shop or next big purchase
  • Emergency back up family care
  • And many more
Equal Employment Opportunity

Our employing entity, Arthur J. Gallagher Services (UK) Limited, is proud to be accredited as a Living Wage employer with the Living Wage Foundation. We are committed to diversity and opportunity for all and are opposed to any form of less favourable treatment on the grounds of gender or gender identity, marital status, civil partnership status, parental status, race, ethnicity, colour, nationality, disability, sexual orientation, religion/ belief, age and those with caring responsibilities.

Gallagher believes that all persons are entitled to equal employment opportunity and prohibits any form of discrimination by its managers, employees, vendors or customers based on race, color, religion, creed, gender (including pregnancy status), sexual orientation, gender identity (which includes transgender and other gender non conforming individuals), gender expression, hair expression, marital status, parental status, age, national origin, ancestry, disability, medical condition, genetic information, veteran or military status, citizenship status, or any other characteristic protected (herein referred to as "protected characteristics") by applicable federal, state, or local laws.

Equal employment opportunity will be extended in all aspects of the employer-employee relationship, including, but not limited to, recruitment, hiring, training, promotion, transfer, demotion, compensation, benefits, layoff, and termination. In addition, Gallagher will make reasonable accommodations to known physical or mental limitations of an otherwise qualified person with a disability, unless the accommodation would impose an undue hardship on the operation of our business.