Contract Senior Java Developer - Data

Quant Capital
London

Contract Senior Java Developer – Data

Up to £700 per day 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:

Java (primary), Python (secondary), AWS, PostgreSQL + Git, CI/CD, logging/monitoring

What they want:

  • 10+ years of experience building production systems (or equivalent ability)
  • Strong Java fundamentals (OO design, APIs/services, concurrency basics, testing)
  • Some UI development
  • 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
Posted 2026-03-12

Recommended Jobs

English Teacher - Mixed School in Lambeth (January Start)

Marchant Recruitment
London

English Teacher – Mixed School in Lambeth (January Start) Location: Lambeth Start Date: January 2026 Contract Type: Full-time, Permanent Salary: Paid to scale A vibrant mixed 11–18 s…

View Details
Posted 2025-11-28

Music Technician - Creative Secondary School - Camden

Marchant Recruitment
London

Music Technician – Creative Secondary School – Camden (London) Start Date: As soon as possible Contract: Full-time, Permanent Salary: Paid to scale (support staff scale depending on experi…

View Details
Posted 2026-03-13

Design & Technology Technician - Wembley

Marchant Recruitment
Harrow, Greater London

A forward-thinking and well-resourced secondary school in Wembley is seeking a skilled and proactive Design & Technology (DT) Technician to support their successful DT department. This is a full-time…

View Details
Posted 2026-02-19

English Specialist | Newham | Modern & Professional...

Marchant Recruitment
Newham, Greater London

An energetic school in Newham needs an English Teacher for a September start. This is a great spot for a teacher who loves literature and wants to help students become confident, articulate writers. …

View Details
Posted 2026-05-01

Client Services Director

Atlantis Health
London

Are you our next Change Agent? We are looking for a Client Services Director with a passion for patient engagement solutions to join dynamic team at Atlantis Health UK. This role is responsible f…

View Details
Posted 2026-08-01

Airside Drivers - London Heathrow Airport (Cargo Terminals) (Hiring Immediately)

Hexagon Recruitment Partners Ltd
Hounslow, Greater London

We are looking for Airside Drivers to join our team at London Heathrow Airport Cargo Terminals. This is a temp-to-perm opportunity with a competitive pay structure and excellent career progression. Y…

View Details
Posted 2026-05-03

Travel Business Development Executive

Platinum Travel Recruitment Ltd
London

Our client is a leading and highly successful Travel Management Company with an outstanding reputation for delivering first-class services to corporate clients. With exciting growth plans ahead, they…

View Details
Posted 2025-09-10

Remote Japanese Tutor - Flexible Hours and Competitive Pay

FindTutors
London

Ready to share your passion for Japanese language and culture? Join our team as an Online Japanese Tutor at FindTutors! We're seeking a dedicated tutor to lead dynamic and immersive Japanese language…

View Details
Posted 2026-04-16

Sales Enablement Specialist

Cognism
London

WHO ARE WE Cognism is the leading provider of European B2B data and sales intelligence. Ambitious businesses of every size use our platform to discover, connect, and engage with qualified decision…

View Details
Posted 2026-07-27

Food Tech Teacher - Kingston - Jan 2026

Marchant Recruitment
Kingston upon Thames, Greater London

Are you an inspirational Food Technology Teacher looking for an exciting opportunity to work in an Outstanding school who will invest in developing your career, subject knowledge and give you the opp…

View Details
Posted 2025-10-31