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- Tasks: Drive performance improvements in applications and infrastructure while collaborating with teams.
- Company: Fully remote role with a dynamic tech company focused on innovation.
- Benefits: Competitive day rate, flexible work environment, and potential for contract extension.
- Why this job: Make a real impact by optimising performance and enhancing user experience.
- Qualifications: Strong background in performance engineering and hands-on expertise in .NET and SQL.
- Other info: Opportunity to work with cutting-edge tools and grow your career in a supportive environment.
Location: Fully Remote (UK)
Day Rate: £400-£450 per day (Inside IR35)
Contract Length: 6 months (Possible Extension)
We’re looking for an experienced Senior Software Engineer (Contract) to join on an interim basis and drive performance improvements across our applications and infrastructure. You’ll be responsible for identifying bottlenecks, putting the right telemetry in place, and helping our teams deliver a faster, more reliable experience for customers at scale.
Key Must Have Skills:
- .NET (C#), DOM performance
- JavaScript
- MS SQL Server, query optimisation, and indexing strategies
- K6, Playwright, AppInsights
- Azure DevOps - CI/CD pipelines and observability tooling
What you’ll be doing:
- Front-end performance: Investigate and optimise browser behaviour, including JavaScript execution, rendering, and DOM interactions.
- Backend performance: Analyse .NET applications for efficiency, memory usage, and concurrency, implementing improvements where needed.
- Database tuning: Optimise SQL queries, indexes, and overall database performance.
- Instrumentation & monitoring: Expand and refine telemetry across the stack using tools such as AppInsights, K6, and Playwright.
- Collaboration: Partner with engineers, testers, and product teams to prioritise performance initiatives, share best practices, and influence long-term improvements.
- Load testing: Support the design and execution of realistic load/performance scenarios to uncover weaknesses and recommend fixes.
What we’re looking for:
- Strong background in performance engineering across browser, server, and database layers.
- Hands-on expertise with:
- JavaScript profiling and browser internals.
- .NET (C#), async programming, concurrency, and memory management.
- SQL Server query tuning and indexing.
- Familiarity with modern observability and testing tools (e.g. K6, Playwright, AppInsights, Azure DevOps).
- Good knowledge of CI/CD practices and performance instrumentation.
Nice to have:
- Experience working with Vue.js or other modern front-end frameworks.
Senior Software Engineer (Contract) employer: Digital Waffle
Contact Detail:
Digital Waffle Recruiting Team
StudySmarter Expert Advice 🤫
We think this is how you could land Senior Software Engineer (Contract)
✨Tip Number 1
Network like a pro! Reach out to your connections in the tech industry, especially those who work with .NET or performance engineering. A personal recommendation can make all the difference when you're applying for that Senior Software Engineer role.
✨Tip Number 2
Show off your skills! Create a portfolio or GitHub repository showcasing your projects, especially those involving JavaScript profiling or SQL Server optimisations. This gives potential employers a taste of what you can do and sets you apart from the crowd.
✨Tip Number 3
Prepare for interviews by brushing up on your performance engineering knowledge. Be ready to discuss your experience with tools like AppInsights and K6, and how you've tackled performance issues in past projects. Confidence is key!
✨Tip Number 4
Don't forget to apply through our website! We love seeing candidates who are proactive and engaged. Plus, it’s a great way to ensure your application gets the attention it deserves.
We think you need these skills to ace Senior Software Engineer (Contract)
Some tips for your application 🫡
Tailor Your CV: Make sure your CV highlights your experience with .NET, JavaScript, and SQL Server. We want to see how your skills match the role, so don’t be shy about showcasing your performance engineering expertise!
Craft a Compelling Cover Letter: Your cover letter is your chance to shine! Use it to explain why you’re the perfect fit for this contract role. Mention specific projects where you’ve optimised performance or improved application reliability.
Showcase Your Problem-Solving Skills: In your application, give examples of how you've tackled performance bottlenecks in the past. We love seeing clear, actionable recommendations that led to real improvements!
Apply Through Our Website: We encourage you to apply directly through our website. It’s the best way for us to receive your application and ensures you don’t miss out on any important updates from our team!
How to prepare for a job interview at Digital Waffle
✨Know Your Tech Inside Out
Make sure you brush up on your .NET (C#), JavaScript, and SQL Server skills. Be ready to discuss specific performance improvements you've made in the past, especially around query optimisation and memory management. The more examples you can provide, the better!
✨Showcase Your Problem-Solving Skills
Prepare to talk about how you've identified bottlenecks in applications before. Think of a few scenarios where you used tools like AppInsights or K6 to diagnose issues and how you implemented solutions. This will show your proactive approach to performance engineering.
✨Communicate Clearly
Since you'll need to collaborate with various teams, practice explaining complex technical concepts in simple terms. You might be asked to present your findings or recommendations, so being a clear communicator is key. Try to keep it straightforward and relatable.
✨Be Ready for Practical Tests
Given the technical nature of this role, expect some practical assessments during the interview. Brush up on your load testing strategies and be prepared to demonstrate your knowledge of CI/CD practices. Familiarity with tools like Azure DevOps will definitely give you an edge!