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

EYFS TA NEEDED IN BRENT

Marchant Recruitment
Brent, Greater London

Job Title: EYFS Teaching Assistant Location: Wembley, North West London Salary: £21,500 – £23,000 FTE (pro-rata for part-time) Contract Type: Full-Time / Part-Time Considered Start Dat…

View Details
Posted 2026-01-16

Occupational Therapy

London

PSL Recruitment Services is recruiting an experienced Occupational Therapist (OT) for an NHS community service in South Central London. The role involves providing specialist OT interventions within…

View Details
Posted 2026-01-06

Teacher of Drama | Islington Secondary School | ASAP Start

Marchant Recruitment
London

We are seeking an enthusiastic Drama Teacher for a high-performing secondary school in Islington. This full-time, permanent role starts ASAP and offers a brilliant opportunity for a creative teacher …

View Details
Posted 2026-03-10

Teacher of Spanish with ECT support - Lovely Outstanding...

Marchant Recruitment
Brent, Greater London

School Status & Location Sector: Outstanding Ofsted Secondary School (with Sixth Form). Borough: Brent (Inner London, England). Start Date: Permanent, full-time role commencing January 2026.…

View Details
Posted 2025-12-13

Digital Engagement Lead (Sweepstake Brands)

Arena Entertainment
London

About Arena Arena is a digital entertainment company building platforms people genuinely love. Since 2021, our portfolio has grown to include MetaWin, WOW Vegas, BetZoo Media, Hit.com , and Roll…

View Details
Posted 2026-05-07

Occupational Therapy

London

PSL Recruitment Services is proud to partner with a leading independent private hospital in London to recruit an experienced Band 6 Senior Occupational Therapist to join their inpatient therapies team…

View Details
Posted 2026-01-27

Virtual School Education Officer - SO1

London Borough of Hillingdon
Hillingdon, Greater London

Job Category : Education (qualified) Client Location : London Borough of Hillingdon Hours Per Week : 36.00 Start Date : Immediate Start               Start Time : 09:00 End Time : 17:00 …

View Details
Posted 2026-05-30

Customer Service Supervisor

St Pancras, Greater London

Booker • 106 Camley St St Pancras London •  Working hours 38•  Apply by 30-Jun-2026

View Details
Posted 2026-05-28

Computer Science Teacher | Hackney (Inner London)

Marchant Recruitment
London

We are working with a school who are recruiting for a talented Computer Science Teacher for a September 2026 start in Hackney. This is a full-time, permanent position in a vibrant, aspirational learn…

View Details
Posted 2026-03-28