Full-Stack Developer – React, React Native & .NET | Maritime Defence | Outside IR35 Contract

About the opportunity

Puma Berry is seeking two Full-Stack Developers, one mid-level and one senior, for an upcoming maritime defence software programme.

You will help develop applications that enable users to record vessel inspections, capture survey data and synchronise information across connected and offline environments. Working within an established Agile team, you will contribute across web, mobile and backend development alongside business analysts, designers, developers and testers.

These opportunities are subject to contract award.

Contract details

• Rate — £425–£525 per day, depending on experience and role level.
• IR35 status — Expected to be outside IR35, subject to confirmation.
• Location — Predominantly remote within the UK, with approximately monthly visits to Bath.
• Start — 23 November 2026, or as soon as practicable afterwards.
• End date — 31 March 2027.
• Equipment — Laptop and development tools provided.
• Working arrangements — All work must be carried out within the UK.

Responsibilities

• Develop and enhance web applications using React.
• Build mobile applications using React Native with Expo.
• Develop RESTful APIs using ASP.NET Core MVC.
• Manage application data using Entity Framework Core and SQL Server.
• Improve survey workflows, assignment tracking, synchronisation and reporting.
• Collaborate with business analysts to clarify and refine requirements.
• Produce maintainable code with clear separation of concerns and extensive unit test coverage.
• Participate in code reviews, technical discussions and demonstrations.
• Keep the Squad Lead informed of progress, blockers and concerns.
• Contribute to monthly project progress reporting.

Essential skills and experience

• At least six months’ experience developing web applications using React.
• At least six months’ experience developing mobile applications using React Native with Expo.
• At least six months’ experience developing RESTful API backends using ASP.NET Core MVC.
• Practical experience using Entity Framework Core with SQL Server.
• Experience working within Agile software development teams.
• Strong unit testing, code review and collaborative development practices.
• Clear communication skills and a constructive approach to working with colleagues.

Experience that would help you stand out

• Developing survey, inspection or field-data collection applications.
• Delivering software within the regulated maritime defence sector.
• Developing mobile applications with offline functionality and data synchronisation.
• Using TanStack Query.
• Using the Royal Navy Design System.

Role levels

The mid-level developer will deliver agreed development tasks under general direction and contribute effectively within the team.

The senior developer will handle more complex technical work independently, contribute to technical discussions and provide constructive guidance to colleagues.

Apply

Please submit your CV with your availability, expected day rate and current clearance status. Highlight your experience across web, mobile and backend development, together with any relevant survey, inspection or maritime projects.

Pay: £425.00-£525.00 per day

Application question(s):

• Do you currently hold UK SC clearance, or are you eligible to obtain it?

Experience:

• ASP.NET Core MVC, Entity Framework Core and SQL Server: 2 years (preferred)
• React and React Native with Expo: 2 years (preferred)

Work Location: Hybrid remote in Bath