Staff Engineer (.Net)

Benifex; Southampton; On-site; GBP 85,000 - 110,000; Full time

Job summary

A leading technology company in Southampton is seeking a Staff Engineer specializing in .NET to drive improvements in their Benefits platform. In this crucial role, you will leverage your technical expertise to lead modernizations and improve system architecture. Ideal candidates will have over 10 years of experience in backend development and be able to collaborate across teams effectively while driving strategic initiatives. This role offers a competitive salary and excellent benefits.

Benefits

Salary range: £85,000-£110,000

Annual learning budget

Flexible work arrangements

Comprehensive benefits package

25 days holiday plus bank holidays

Birthday day off

Healthcare cash plan

Enhanced parental leave package

Work from Anywhere policy for 90 days

Monthly personal allowance

Qualifications

• 10+ years of progressive experience in backend development.
• Exceptional technical leadership skills.
• Proven ability to solve complex business problems.

Responsibilities

• Define and evolve the long term technical vision for the product.
• Act as the primary technical authority for C#.NET solutions.
• Lead the modernisation strategy towards a cloud-native architecture.

Skills

C#.NET

.NET Core

Kubernetes

Cloud-native solutions

CI/CD pipelines

Communication

Tools

Google Cloud Platform

Redis

Grafana

Job description

Who are Benifex? 💚💜

We are a fast‑moving technology company, and one of the most successful providers of online reward and benefits solutions in the world. We believe that everyone deserves an exceptional experience at work, every day, and build workplace technology that makes this happen. Benifex’s mission is to build remarkable experiences that employees love. Today Benifex supports more than five million employees in over 3,000 organisations across more than 100 countries. To help us on our quest to be the best, we need brilliant people on board and that’s where you come in. 🚀

Why should you apply? 🌟

• Challenge: exciting opportunity to drive the evolution of a key product by implementing cutting‑edge technology, refining technical best practices, and fostering collaboration across global teams
• Impact: you’ll be working across a number of teams delivering real impact, focusing on proactively identifying issues and leaving each team in a better position than you found it!
• Ownership: you will be our technical .Net expert within the business and act as a point of technical expertise on a number of different business‑critical projects
• Top 10 Employer, Sunday Times Best Places to Work Awards
• Work for a profitable, fast‑growing market leader in the online reward and benefits space

**Please note we are unable to offer visa sponsorship and require to people to be based in the UK or Ireland for this position**

Great benefits:

💰 £85,000‑110,000

💻 Tech setup of your choice (MacBook Pro or equivalent, monitors, etc.)

📚 £/€800 annual learning budget, plus two hours per week as ‘Focus Fridays’.

🤸 Flexible work – choose a working setup that works for you, our only ask is to see you once a month in the office and you must be based in the UK or Ireland.

💸 Full access to our comprehensive benefits package, including discounts from hundreds of high street brands, salary sacrifice schemes across Finance, Health, Tech, and more

✈️ 25 days holiday plus your local bank holidays

🎂 Your birthday off

❤️ Two half day wellbeing days

🩺 Healthcare cash plan to cover the costs of day‑to‑day healthcare

🧠 Employee Assistance Plan 24/7 365 support

🤒 Income Protection (75%) and life assurance (4x salary)

💰 Referral bonuses

🌟 Enhanced parental leave package – 26 weeks fully paid maternity leave and 4 weeks fully paid paternity leave

✈️ Work from Anywhere policy for 90 days

🏖️ Buy and Sell scheme for holidays

💳 £50 monthly allowance to spend on whatever takes your fancy, your very own Benifex card will be topped up at the start of each month!

Role Overview 🚀

We’re hiring for a Staff Engineer with a focus on .NET to help drive improvements across a number of teams focused on our Benefits platform. You’ll be focusing on driving procedural and technical improvements proactively, with a focus on leaving each team in a better position than you found it.

This is a crucial role in continually improving our product offering and you’ll be driving those improvements through your technical expertise, stakeholder management, and broader product knowledge.

Responsibilities 🤘

• Work with the Architect to define, own and evolve the long term technical vision and architectural roadmap core Benefits product platform, ensuring alignment with overall business strategy and engineering excellence goals.
• Act as the primary technical authority and deep subject matter expert for C#.NET, .NET Core, and cloud‑native solutions, resolving the most complex architectural and performance challenges.
• Lead the modernisation strategy from existing systems to a robust, scalable cloud‑native architecture utilizing Kubernetes/GKE and Google Pub/Sub, setting the standard for implementation across engineering teams.
• Work across the Benefits teams and workstreams to lead the design and hands‑on development of complex, highly‑available, and scalable backend solutions for our Benefits product using C#.NET and .NET Core.
• Design and champion the end‑to‑end CI/CD and deployment strategy, focusing on advanced techniques for canary deployments, blue/green strategies, and automated reliability testing.
• Proactively collaborate with Principal/Staff Engineers and Product Leadership across the organization to resolve technical trade‑offs, align dependencies, and drive strategic initiatives that span multiple engineering teams.
• Provide deep technical mentorship and coaching to Senior and mid‑level engineers, elevating the overall technical capabilities and domain knowledge of the department.
• Partner with engineers from diverse backgrounds (e.g., Java Spring Boot teams) to design robust integration contracts and spearhead knowledge transfer to build a cohesive, unified engineering culture.

Tech stack: .NET, SQL, GCP, MSMQ (moving to Google Pub/Sub), Kubernetes.

What are we looking for? 🔎

• 10+ years of progressive experience in backend development, with extensive, expert‑level proficiency in C#.NET and .NET Core, designing and implementing systems at scale.
• Exceptional technical leadership skills with the ability to influence technical decisions across multiple teams without direct management authority.
• Highly effective communication—the ability to articulate complex technical issues and architectural proposals clearly to both engineers and non‑technical executives.
• Architectural ownership and ambiguity tolerance—proven ability to take ownership of open‑ended, complex business problems and drive them to a robust technical solution with minimal guidance.
• Proven knowledge of Kubernetes and containerisation to support modern infrastructure practices.
• Experience with modern architectural patterns, including microservices and event‑driven systems.
• Hands‑on experience with messaging systems like Pub/Sub, distributed transaction coordination (MSDTC), and caching solutions like Redis.
• Proven ability to set up and maintain CI/CD pipelines to streamline development and deployment workflows.
• Solid understanding of system performance, optimisation, and debugging.
• Collaboration: Ability to work effectively with cross‑functional and remote teams, including Java Spring Boot engineers, to deliver cohesive solutions.
• Proactive Problem‑Solving: A resourceful approach to tackling complex challenges and driving projects forward with minimal guidance.
• Technical Excellence: A strong advocate for clean code, best practices, and high‑quality software development.

Bonus Points for:

• Experience with cloud technologies, particularly in deploying and scaling .NET applications.
• Familiarity with observability tools for monitoring, logging, and alerting (e.g., Grafana, Prometheus).
• Knowledge of IaC tools such as Terraform.
• Previous experience modernising legacy systems or transitioning monolithic architectures to microservices.

Even if you don’t meet all of the requirements for this role, we encourage you to apply! We are looking for talented and passionate individuals who are eager to learn and grow. We also offer a variety of other roles, so please check out our careers page to see if there is something else that might be a good fit for you.

Our interview process

Benifex understands the need to have a fast and efficient process, the below will all be completed in the shortest time possible.

📞 Initial informal call with the Talent team

⏳ Interview with our Engineering Manager 30 min

🧪 Technical Task

🔎 Technical Interview – 60 min

🤩 Final interview with VP of Engineering – 30‑45 min

We are an equal opportunity employer and value diversity at our company. We do not discriminate on the basis of race, religion, colour, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status.

We are committed to creating a diverse and inclusive workplace where everyone feels welcome and respected. We believe that diversity and inclusion are essential to our success, and we are proud to be an equal opportunity employer.

We are a proud member of the Disability Confident employer scheme.

If you require any reasonable adjustments at any stage during the recruitment process, please let us know with your application.