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# Contract Senior Java Developer - Data

- **Company:** Quant Capital
- **Location:** London, UK
- **Experience:** Expert
- **Contract:** Temporary contract
- **Skills:** Java (Programming Language), Application Programming Interfaces (APIs), Amazon Web Services, Code Review, Continuous Integration, Data Validation, Information Engineering, Extract Transform Load (ETL), Software Debugging, Python (Programming Language), PostgreSQL, Object-Oriented Software Development, SQL Databases, Data Logging, Data Ingestion, Concurrency, Git
- **Published:** August 11, 2026
- **Apply:** https://find.jobs/jobs-near-me/apply/ats-redirect/?id=2918914121-2

## About the Role

AWS, PostgreSQL + Git, CI/CD, logging/monitoringWhat they want:10+ years of experience building production systems (or equivalent ability)Strong Java fundamentals (OO design, APIs/services, concurrency basics, testing)Some UI developmentComfortable with SQL/PostgreSQLSome Python experience (enough to manage and improve existing ETL/ingestion)Nice to haveAny finance or markets exposureFamiliarity with common AWS patterns for running services and pipelinesWhy this roleBroader scope than pure app dev: you'll understand the data feeding the platformLean team, high impact, strong growth runway

## Description

Contract Senior Java Developer - Data Up to 700 per day Outside IR35 (6 month rolling)In office - City of LondonQuant 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 businessWrite 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/CDTech:Java (primary), Python (secondary)


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