Java Software Engineer – Data EngineeringUp to £100,000 + bonus and benefits4:1 hybrid 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), AWS, PostgreSQL + Git, CI/CD, logging/monitoringWhat they want:2–5 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 runwayMy client is based London. Home work is encouraged but you will need to be able to come to the City if needed.