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- Tasks: Build cutting-edge systems for quant researchers using functional programming and Python.
- Company: Top-tier quantitative research firm with advanced trading platforms.
- Benefits: Competitive salary, remote work options, and opportunities for professional growth.
- Why this job: Join a team that values functional design and makes a real impact in tech.
- Qualifications: 4+ years in software engineering with a focus on functional programming.
- Other info: Exciting opportunity to work on large-scale distributed systems.
The predicted salary is between 36000 - 60000 £ per year.
Functional Software Engineer – Research & Quant Foundations (RQF)
You must have experience in Functional programming, using one of the following: F#, Haskell, Rust, Lisp, Erlang, OCaml, Caml along with Python. You will not be considered if you haven't.
Experience: 4 years, varying levels of experience being considered.
Hires: 3+
We’re working with a top-tier quantitative research and systematic trading firm operating one of the most advanced trading platforms in the world. Their systems are fully automated, globally distributed, and run at extreme scale - executing millions of trades per day. Platform resilience, uptime, and operational efficiency are mission-critical.
As a Functional Software Engineer within the Research & Quant Foundations (RQF) group, you’ll sit at the core of the platform, building systems that enable quant researchers to move faster across a vast compute estate. The focus is on abstracting complexity, improving developer experience, and ensuring large-scale research workloads run smoothly and reliably. This is a high-bar engineering role for people who care deeply about functional design, correctness, and software quality.
What you’ll be working on:
- A core scheduling platform written in F#, responsible for distributing very large workloads across massive compute farms
- Python and .NET SDKs that form the primary day-to-day interface used by researchers
- A TypeScript/React UI backed by an F# ASP.NET service, Postgres, and Kubernetes, providing real-time visibility into workload execution
- Tooling and frameworks that enable researchers to build and deploy research platforms and express computations over streaming data
- Foundational systems designed for performance, safety, expressiveness, and long-term maintainability
The codebase is approximately 75% F#, with the remaining 25% primarily Python and Rust. Day-to-day work includes high-end, production-grade Python, but the engineering culture is strongly rooted in functional programming principles.
What they’re looking for:
- Strong interest and experience in functional programming
- 4+ years of software engineering experience in high-bar environments
- Excellent programming ability with a deep focus on code quality and design
- Experience with one or more of: F#, Haskell, Rust, Lisp, Erlang, OCaml, Caml, or similar
- Professional Python experience beyond scripting or notebooks
- An engineer who genuinely cares about developer experience
- Exposure to compiler work or language tooling is a strong plus
- MSc or PhD in Computer Science (or equivalent depth of technical background) is highly desirable
This team hires exceptionally well and is scaling deliberately, with three new hires planned. If you’re excited by functional programming, large-scale distributed systems, and building foundational tooling that world-class researchers rely on every day, this is a standout opportunity.
Functional Software Engineer in London employer: Arcus Search
Contact Detail:
Arcus Search Recruiting Team
StudySmarter Expert Advice 🤫
We think this is how you could land Functional Software Engineer in London
✨Tip Number 1
Network like a pro! Reach out to folks in the industry on LinkedIn or at meetups. We all know that sometimes it’s not just what you know, but who you know that can land you that dream job.
✨Tip Number 2
Show off your skills! Create a GitHub profile showcasing your projects in functional programming. We want to see your code quality and design chops in action, so make sure it’s polished and ready to impress.
✨Tip Number 3
Prepare for those technical interviews! Brush up on your functional programming concepts and be ready to discuss your past experiences. We recommend practicing coding challenges to keep your skills sharp.
✨Tip Number 4
Apply through our website! It’s the best way to ensure your application gets seen by the right people. We’re excited to find passionate engineers who care about developer experience just as much as we do.
We think you need these skills to ace Functional Software Engineer in London
Some tips for your application 🫡
Show Off Your Functional Skills: Make sure to highlight your experience with functional programming languages like F#, Haskell, or Rust. We want to see how you've used these skills in real-world projects, so don’t hold back!
Quality Over Quantity: When detailing your experience, focus on the quality of your work rather than just listing jobs. We care about your coding ability and how you approach software design, so share specific examples that showcase your best work.
Tailor Your Application: Don’t send a generic application! Tailor your CV and cover letter to reflect the job description. Mention how your background aligns with our needs, especially around developer experience and large-scale systems.
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 in our team!
How to prepare for a job interview at Arcus Search
✨Know Your Functional Programming Inside Out
Make sure you brush up on your knowledge of functional programming languages like F#, Haskell, or Rust. Be ready to discuss specific projects where you've applied these skills, and don't shy away from explaining the principles behind functional design and how they improve code quality.
✨Showcase Your Python Expertise
Since professional Python experience is a must, prepare to talk about your past work with Python beyond just scripting. Highlight any production-grade projects you've worked on, especially those that demonstrate your ability to write clean, efficient, and maintainable code.
✨Demonstrate Your Problem-Solving Skills
Expect technical questions that assess your problem-solving abilities. Practice coding challenges that require you to think critically and apply functional programming concepts. This will not only show your technical prowess but also your approach to tackling complex problems.
✨Understand the Company’s Tech Stack
Familiarise yourself with the technologies mentioned in the job description, such as Kubernetes, Postgres, and TypeScript/React. Being able to discuss how these tools fit into the larger picture of the company’s operations will demonstrate your genuine interest and preparedness for the role.
