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- Tasks: Build and enhance Java backend services while managing Python ETL/data ingestion.
- Company: Join a high-performing market maker in the heart of London.
- Benefits: Competitive pay, flexible working, and opportunities for professional growth.
- Why this job: Make a real impact in a lean team with a focus on data and innovation.
- Qualifications: 10+ years in production systems, strong Java skills, and some Python experience.
- Other info: Dynamic environment with excellent career advancement potential.
The predicted salary is between 60000 - 80000 £ per year.
Outside IR35 (6 month rolling) In office – City of London. Quant Capital is hiring for a small, high-performing market maker in London. This is a junior‑to‑mid role focused primarily on Java development, with a secondary responsibility owning straightforward Python ETL/data ingestion into AWS and PostgreSQL. This is a growing team focused on data ingestion and building tooling for the wider firm.
What you’ll do:
- Build and enhance Java backend services (APIs, batch jobs, integrations) used across the business
- Write clean, testable code with solid engineering discipline (testing, code review, debugging, production support)
- Maintain and extend Python-based ingestion/ETL (pragmatic plumbing, not heavy data engineering)
- Work with PostgreSQL (schemas, migrations, performant queries, data validation)
- Improve service reliability: monitoring/logging, sensible alerting, and predictable deployments via CI/CD
Tech:
- 10+ years of experience building production systems (or equivalent ability)
- Comfortable with SQL/PostgreSQL
- Some Python experience (enough to manage and improve existing ETL/ingestion)
Nice to have:
- Any finance or markets exposure
- Familiarity with common AWS patterns for running services and pipelines
Why this role:
- Broader scope than pure app dev: you’ll understand the data feeding the platform
- Lean team, high impact, strong growth runway
Contract Senior Java Developer – Data in London employer: Quant Capital
Contact Detail:
Quant Capital Recruiting Team
StudySmarter Expert Advice 🤫
We think this is how you could land Contract Senior Java Developer – Data in London
✨Tip Number 1
Network like a pro! Reach out to your connections in the industry, especially those who work in finance or market making. A friendly chat can lead to insider info about job openings that aren't even advertised yet.
✨Tip Number 2
Show off your skills! If you’ve got a GitHub or portfolio showcasing your Java and Python projects, make sure to share it during interviews. It’s a great way to demonstrate your coding chops and problem-solving abilities.
✨Tip Number 3
Prepare for technical interviews by brushing up on your SQL and PostgreSQL knowledge. Practice common coding challenges and be ready to discuss how you've improved ETL processes in past roles. Confidence is key!
✨Tip Number 4
Don’t forget to apply through our website! We’re always on the lookout for talented developers like you. Plus, it shows you’re genuinely interested in joining our team and makes it easier for us to find your application.
We think you need these skills to ace Contract Senior Java Developer – Data in London
Some tips for your application 🫡
Tailor Your CV: Make sure your CV highlights your Java development experience and any relevant Python skills. We want to see how your background aligns with the role, so don’t be shy about showcasing your achievements in building production systems.
Craft a Compelling Cover Letter: Your cover letter is your chance to shine! Use it to explain why you’re excited about this role and how your experience can contribute to our team. We love seeing genuine enthusiasm and a clear understanding of what we do.
Showcase Your Technical Skills: When detailing your experience, focus on your work with Java, SQL/PostgreSQL, and any Python ETL projects. We’re keen on seeing examples of clean, testable code and how you’ve improved service reliability in past roles.
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. Plus, it makes the process smoother for everyone!
How to prepare for a job interview at Quant Capital
✨Know Your Java Inside Out
Make sure you brush up on your Java skills before the interview. Be ready to discuss your experience with building backend services, APIs, and batch jobs. Prepare to showcase your understanding of clean coding practices and how you've applied them in past projects.
✨Get Comfortable with PostgreSQL
Since this role involves working with PostgreSQL, it’s crucial to be familiar with schemas, migrations, and writing performant queries. Practise explaining your approach to data validation and any challenges you've faced while working with databases.
✨Brush Up on Python ETL Basics
Even though the focus is on Java, having a solid grasp of Python for ETL processes is essential. Be prepared to discuss your experience with data ingestion and how you’ve managed or improved existing ETL pipelines in previous roles.
✨Show Your Interest in Finance and Markets
If you have any experience or knowledge about finance or market-making, make sure to highlight it during the interview. This can set you apart from other candidates and show that you're genuinely interested in the industry and the role.