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For Companies At a Glance
- Tasks: Design and develop cutting-edge trading systems while supporting live production environments.
- Company: Dynamic financial trading firm based in London with a collaborative culture.
- Benefits: Competitive salary, flexible working arrangements, and direct exposure to live trading systems.
- Why this job: Join a fast-paced environment and make a real impact on innovative trading technology.
- Qualifications: 5+ years in software development with strong C# and .NET skills.
- Other info: Great opportunity for career growth in a high-impact role.
The predicted salary is between 36000 - 60000 £ per year.
Location: London (City) – Hybrid / On-site / Remote
We are a London-based financial trading firm seeking an experienced Software Engineer to join our development team and support the ongoing evolution of our in-house trading and brokerage systems. This is a hands-on, business-critical role within a fast-paced trading environment. You will work directly with the Head of Development and collaborate closely with trading, operations, and infrastructure teams to maintain and enhance a proprietary platform used daily across Europe, the US, and Asia.
The Opportunity
You will play a key role in developing, supporting, and modernising core trading systems covering trade booking, P&L and risk capture, confirmations, reporting, and messaging integrations. This role combines active software development with live production support and direct engagement with front-office stakeholders.
Key Responsibilities
- Design, develop, and maintain in-house trading and booking systems
- Contribute hands-on to daily development in C# / .NET
- Review and improve code quality, performance, and security
- Support architectural decisions and technical roadmap initiatives
- Enhance system stability, scalability, and resilience
- Assist in modernising legacy applications, including migration initiatives
- Provide support within live trading environments
- Diagnose and resolve complex technical and business-critical issues
- Translate business requirements into effective technical solutions
- Coordinate with Infrastructure and IT Support teams
Technical Environment
- C#
- Microsoft SQL Server
- In-house FIX engine
- Excel VBA-based systems
- Fully in-house developed platform
Skills & Experience
- 5+ years’ professional software development experience
- Strong expertise in C# and .NET (modern .NET advantageous)
- Experience maintaining and enhancing legacy systems
- Solid SQL Server and database design knowledge
- Experience with message brokers (e.g., RabbitMQ)
- Understanding of distributed systems
- Experience within financial services, brokerage, or trading environments
- Knowledge of equity and/or derivatives trading workflows
- Strong analytical and problem-solving skills
- Ability to operate effectively in high-pressure, business-critical environments
Highly Desirable
- Trading platform or booking system experience
- FIX protocol knowledge
- VBA experience
- Experience migrating WinForms applications to modern architectures
- Azure cloud architecture exposure
- CI/CD and automation experience
Profile
We are looking for a motivated, commercially aware engineer who is:
- Comfortable working with responsibility and autonomy
- A strong communicator across technical and non-technical teams
- Pragmatic and solution-focused
- Willing to take ownership and contribute beyond defined responsibilities
What We Offer
- High-impact role within a growing financial firm
- Direct exposure to live trading systems
- Competitive compensation package
- Flexible working arrangements
- Opportunity to contribute to the long-term evolution of a proprietary trading platform
Software Engineer in London employer: Marlin Selection Ltd
Contact Detail:
Marlin Selection Ltd Recruiting Team
StudySmarter Expert Advice 🤫
We think this is how you could land Software Engineer in London
✨Network Like a Pro
Get out there and connect with people in the industry! Attend meetups, webinars, or even casual coffee chats. You never know who might have the inside scoop on job openings or can put in a good word for you.
✨Show Off Your Skills
Don’t just talk about your experience; demonstrate it! Create a portfolio showcasing your projects, especially those related to trading systems or C#. This will give potential employers a taste of what you can bring to the table.
✨Ace the Interview
Prepare for technical interviews by brushing up on your coding skills and understanding of financial systems. Practice common interview questions and be ready to discuss how you've tackled challenges in past roles.
✨Apply Through Our Website
Make sure to apply directly through our website! It’s the best way to ensure your application gets seen by the right people. Plus, we love seeing candidates who take that extra step to connect with us.
We think you need these skills to ace Software Engineer in London
Some tips for your application 🫡
Tailor Your CV: Make sure your CV is tailored to the Software Engineer role. Highlight your experience with C# and .NET, and don’t forget to mention any relevant projects or achievements that showcase your skills in financial services or trading environments.
Craft a Compelling Cover Letter: Your cover letter is your chance to shine! Use it to explain why you’re passionate about this role and how your background makes you a perfect fit. Be sure to mention your problem-solving skills and experience in high-pressure environments.
Showcase Your Technical Skills: In your application, be specific about your technical expertise. Mention your experience with SQL Server, message brokers, and any work you've done on modernising legacy systems. This will help us see how you can contribute to our team right away!
Apply Through Our Website: We encourage you to apply through our website for the best chance of getting noticed. It’s the easiest way for us to keep track of your application and ensure it reaches the right people. Don’t miss out!
How to prepare for a job interview at Marlin Selection Ltd
✨Know Your Tech Inside Out
Make sure you brush up on your C# and .NET skills before the interview. Be ready to discuss your past projects and how you've tackled challenges in software development, especially in high-pressure environments like trading.
✨Understand the Business
Familiarise yourself with financial trading concepts and workflows. Knowing how trade booking, P&L, and risk capture work will help you connect better with the team and show that you're not just a techie but also understand the business side of things.
✨Prepare for Problem-Solving Questions
Expect to face technical questions that test your analytical and problem-solving skills. Practice coding challenges and be ready to explain your thought process clearly, as this role involves diagnosing complex issues in live trading systems.
✨Show Your Collaborative Spirit
This role requires working closely with various teams, so be prepared to discuss your experience in cross-functional collaboration. Highlight instances where you've effectively communicated with non-technical stakeholders or contributed beyond your defined responsibilities.
