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

AV Technician - Independent School in Westminster!

Marchant Recruitment
London

This may be the AV Technician opportunity you’ve been looking for… A well-regarded educational institution in Westminster is seeking a skilled and reliable AV Technician to join its technical suppo…

View Details
Posted 2026-02-04

Senior Design Manager (Data Centres) - London or Bicester

London

Senior Design Manager (Data Centres) - London or Bicester RED are an expanding international M&E consultancy, with a proven track record in low energy design, focused on providing excellent desi…

View Details
Posted 2026-04-18

Psychometrist

Thames Valley District School Board
London

Psychometrist PSYCHOMETRIST POSITION TITLE:Psychometrist (0.8 FTE) SALARY RANGE: $72,614 - $97,090 per year (based on a 1.0 FTE) DATE OF VACANCY: 2026 September 2 APPLICATION DEADLINE: 2026 Ju…

View Details
Posted 2026-07-01

LKS2 Teacher | Vibrant Primary School in Hillingdon |...

Marchant Recruitment
Hillingdon, Greater London

A thriving and inclusive primary school in Hillingdon is looking to appoint a passionate and skilled Year 4 Class Teacher to join their dedicated Key Stage 2 team from January 2026 . This is an ex…

View Details
Posted 2025-10-11

Psychology ECT - Independent Girls’ School in Kingston

Marchant Recruitment
Kingston upon Thames, Greater London

Psychology ECT – Independent Girls’ School in Kingston (January Start) Location: Kingston Start Date: January 2026 Contract Type: Full-time, Permanent Salary: Paid to scale An establ…

View Details
Posted 2026-01-07

PR & VIP Manager

REISS
London

What’s the role about? We’re looking for a PR & VIP Manager to shape and protect the Reiss brand image across press, VIP relations, and key cultural moments. You will lead seasonal PR and VIP strat…

View Details
Posted 2026-05-27

Chef De Partie

Restaurant Associates
London

Job Details This is an excellent opportunity for an up-and-coming chef who is eager to develop their skills, gain exposure to premium hospitality, and learn from experienced culinary professionals…

View Details
Posted 2026-06-27

Backend Engineer (Hiring Immediately)

Weekday AI
London

This role is for one of the Weekday's clients Salary range: Rs 13000000 - Rs 16000000 (ie INR 130-160 LPA) Min Experience: 5 years Location: London JobType: full-time We are seeking…

View Details
Posted 2026-05-06

Music Teacher - Immediate requirement in Central London

Marchant Recruitment
London

Music Teacher | Hackney | April/September Start Role: Music Teacher (KS3 – KS5) Location: Hackney, East London Contract: Full-Time, Permanent/Long-term Salary: MPS/UPS (Inner London We…

View Details
Posted 2026-02-10

Teacher of Girls' PE - Independent Barnet School

Marchant Recruitment
Barnet, Greater London

We are working with a prestigious independent all-girls school in Barnet recruiting for a Teacher of PE. This is an opportunity to join a high-achieving environment where girls' sport is a flagship…

View Details
Posted 2026-01-28