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- Tasks: Develop and enhance secure web applications using cutting-edge .NET technologies.
- Company: Join Advanced Secure Technologies, a fast-growing company on a mission to combat document fraud.
- Benefits: Enjoy a competitive salary, performance bonuses, and a fun, supportive culture.
- Why this job: Shape the future of enterprise applications and work with innovative tech.
- Qualifications: 7+ years in C# .NET development and strong problem-solving skills required.
- Other info: Great career growth opportunities and a dynamic team environment.
The predicted salary is between 57250 - 66275 £ per year.
Location: Cardiff (Office-based, 5 days a week)
Salary: £57,250 - £66,275 base (DOE) + up to £3,000 annual bonus
Start Date: Early 2026
Job Overview: Are you an accomplished Senior Software Developer with a proven track record in .NET? Join us at an exciting time in our journey, where you'll help shape the future of our products as we modernise our enterprise applications with cutting-edge .NET technologies and event-driven SaaS microservice architecture to deliver enterprise-scale solutions. At Advanced Secure Technologies, we’re a fast-growing, innovative company on a mission to protect organisations from document fraud through cutting-edge security solutions. Based on site in St Mellons, Cardiff, we’re expanding and need another skilled developer to help us scale.
What You'll Do:
- Develop and enhance our secure web applications using .NET
- Apply best practices to write clean, maintainable, testable code
- Collaborate with other talented developers, taking on complex challenges
- Share ideas, solve problems, and help shape the future of our products
Requirements:
- 7+ years' commercial experience in modern C# .NET development, including time at senior level.
- Proven ability in maintaining high testing standards (unit and integration tests)
- Some experience of Clean Architecture, or similar (hexagon/onion etc) beyond traditional N-tier designs
- Strong problem-solving skills, attention to detail, and excellent communication
- Ability to mentor, guide and lead other developers, influencing technical direction and best practices
Bonus Points:
- Working with enterprise-scale software, microservices, event-driven architecture or SaaS product development
- Experience with some of the tech we use: .NET Blazor, EF Core, SQL, Redis, Elasticsearch, RabbitMQ, Docker, Kubernetes or Blockchain
- Experience with TDD, DDD, secure coding/OWASP practices, Azure DevOps, CI/CD pipelines and cloud platforms like Azure
Benefits:
- Competitive salary £57,250 - £66,275 (DOE) + monthly performance bonus
- A clear career pathway through our Senior Developer grades and beyond, with mentoring and skill development support
- 25 days holiday + Bank Holidays
- Training and development time, plus training budgets for courses/exams
- Free gym, secure parking, free eyecare, and a fully stocked kitchen
- Access to PerkBox significant retailer discounts
- Free private online GP
- Employee Assistance Programme including specialist clinical support
- Company car and cycle-to-work schemes
- A fun, supportive culture with birthday treats and epic office events
Selection Process:
- Introductory call (45m): A chance for us to get to know you, and for you to get to know us. We’ll cover your experience, a few competency-based questions, and some light technical discussion
- Technical assessment (90m): Technical questions and discussion around your approach and problem-solving, includes a 30-minute practical coding exercise
- Final conversation (20m): Meet our Managing Director for an informal chat about the role, the team, and your potential impact
Location and Hours:
Onsite, Eastern Business Park, St Mellons, Cardiff, Wales. Min Hours: 37.5hrs per week, 8.30am to 5pm Monday to Friday, with up to one hour for lunch.
If you're ready to accelerate your development career, gain hands-on experience with the latest Microsoft technologies, and work towards becoming a Senior Developer, apply now - we can’t wait to see what you’ll bring!
On Site Working:
We’re an office-based team because our culture thrives on collaboration and hands-on support, especially as we grow quickly and onboard new team members. While we don’t offer fully remote or fixed hybrid work, we’re flexible when life happens - ad hoc home working is always an option.
Diversity & Inclusion:
Advanced Secure Technologies is an equal opportunity employer, proud of our ongoing efforts to foster diversity and inclusion. We welcome applicants from all backgrounds and process your personal data in accordance with our Privacy Notice.
Senior Software Developer in Cardiff employer: Advanced Secure Technologies
Contact Detail:
Advanced Secure Technologies Recruiting Team
StudySmarter Expert Advice 🤫
We think this is how you could land Senior Software Developer in Cardiff
✨Tip Number 1
Network like a pro! Reach out to your connections in the tech industry, especially those who might know someone at Advanced Secure Technologies. A personal referral can make all the difference in getting noticed.
✨Tip Number 2
Prepare for that technical assessment! Brush up on your .NET skills and be ready to showcase your problem-solving abilities. Practising coding challenges can help you feel more confident when it’s time to shine.
✨Tip Number 3
Don’t underestimate the power of a good chat! Use the introductory call to not only share your experience but also to ask questions about the team and culture. This shows your genuine interest and helps you gauge if it’s the right fit.
✨Tip Number 4
Follow up after your interviews! A quick thank-you email can keep you fresh in their minds and show your enthusiasm for the role. Plus, it’s a great opportunity to reiterate why you’re the perfect fit for the team.
We think you need these skills to ace Senior Software Developer in Cardiff
Some tips for your application 🫡
Tailor Your CV: Make sure your CV is tailored to the Senior Software Developer role. Highlight your experience with .NET and any relevant projects you've worked on. We want to see how your skills align with what we're looking for!
Craft a Compelling Cover Letter: Your cover letter is your chance to shine! Use it to tell us why you're passionate about this role and how you can contribute to our mission at Advanced Secure Technologies. Keep it engaging and personal.
Showcase Your Problem-Solving Skills: In your application, don’t forget to mention specific examples of how you've tackled complex challenges in your previous roles. We love seeing how you approach problems and come up with innovative solutions!
Apply Through Our Website: We encourage you to apply directly through our website. It’s the best way to ensure your application gets into the right hands. Plus, it shows us you're keen to join our team!
How to prepare for a job interview at Advanced Secure Technologies
✨Know Your .NET Inside Out
Make sure you brush up on your .NET skills, especially the latest features and best practices. Be prepared to discuss your experience with C# and how you've applied it in real-world projects, as this will likely come up during technical discussions.
✨Showcase Your Problem-Solving Skills
During the interview, be ready to tackle some coding challenges. Practice common algorithms and data structures, and think aloud while solving problems. This will demonstrate your thought process and problem-solving abilities, which are crucial for a Senior Software Developer role.
✨Prepare for Technical Assessments
Expect a technical assessment that includes both theoretical questions and practical coding exercises. Familiarise yourself with Clean Architecture and event-driven design patterns, as these are key components of the role. Review your past projects where you've implemented these concepts.
✨Engage with the Team Culture
Since the company values collaboration, show your enthusiasm for teamwork. Prepare examples of how you've mentored others or contributed to team success in previous roles. This will help you connect with the interviewers and demonstrate that you're a good fit for their culture.
