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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 working, and potential for contract extension.
- Other info: Join a collaborative environment with opportunities for professional growth.
- Why this job: Make a real impact by optimising performance and enhancing user experience.
- Qualifications: Strong background in performance engineering and expertise in .NET, JavaScript, and SQL Server.
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 industry, attend meetups, and engage in online communities. You never know who might have a lead on that perfect Senior Software Engineer role.
✨Tip Number 2
Show off your skills! Create a portfolio or GitHub repository showcasing your projects, especially those involving .NET, JavaScript, and performance engineering. This gives potential employers a taste of what you can do.
✨Tip Number 3
Prepare for interviews by brushing up on your technical knowledge and problem-solving skills. Practice common coding challenges and be ready to discuss your experience with performance optimisation and database tuning.
✨Tip Number 4
Apply through our website! We make it easy for you to find roles that match your skills. Plus, it shows you're genuinely interested in joining our team and helps us get to know you better.
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 align with the performance engineering focus of the role, so don’t hold back on showcasing relevant projects!
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 experiences where you've optimised performance or collaborated with teams to drive improvements.
Showcase Your Technical Skills: In your application, be sure to highlight your hands-on expertise with tools like K6, Playwright, and AppInsights. We love seeing candidates who can demonstrate their knowledge of CI/CD practices and performance instrumentation.
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’re considered for this exciting opportunity. Don’t miss out!
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 implemented telemetry or monitoring tools like AppInsights or K6 to improve performance. This will show that you can think critically and act proactively.
✨Collaboration is Key
Since this role involves working closely with engineers and product teams, be ready to discuss how you've collaborated in the past. Share examples of how you’ve influenced performance initiatives and shared best practices. Communication is crucial, so highlight your ability to convey complex ideas clearly.
✨Get Familiar with CI/CD Practices
As this position requires knowledge of Azure DevOps and CI/CD pipelines, make sure you understand how these processes work. Be prepared to discuss how you've used these tools to enhance performance and reliability in previous projects. Showing that you're up-to-date with modern practices will give you an edge.