Software Engineer - Data (Java / Kotlin / Python)

Arcus Search; Greater London; On-site; GBP 96,000 - 144,000; Full time

Job summary

Arcus Search is seeking a Data-focused Software Engineer to join a premier quantitative research and trading firm in Greater London. This 6-month contract is onsite with potential for hybrid, focusing on reference data pipelines and large-scale market datasets.

You will own and modernise data flows, convert legacy JVM pipelines, and collaborate across SQL Server, Spark, and Python tooling to deliver high-quality, reliable data for research and trading use cases.

Qualifications

• Experience building or modernising data pipelines.
• Strong JVM background with SQL/data processing knowledge.
• Financial markets data experience is a plus but not required.

Responsibilities

• Own and enhance data pipelines processing large-scale financial market data.
• Modernise existing data flows and upgrade legacy JVM pipelines.
• Remap incoming datasets and rewrite ingestion/transform pipelines.
• Work across SQL Server, JVM apps, and Spark workloads.

Skills

JVM background

Data pipelines

SQL

Performance pipelines

Financial markets data

Tools

Kotlin

Spring Boot

Python

Spark

SQL Server

Job description

Software Engineer - Data (Java / Kotlin / Python)

Do not apply if you do not have experience within Financial services, working with Java data pipelines as you will not be considered.

6-month initial contract | Onsite (potential for hybrid)

An elite quantitative research and trading firm is looking for a Data focused Software Engineer to join a Reference Data team supporting critical research and trading use cases.

This team owns complex financial market datasets that describe how markets are structured and behave, and plays a key role in ensuring high-quality, reliable data flows across the organisation.

What you’ll be doing

• Owning and enhancing data pipelines that process large-scale financial market data
• Modernising existing data flows, upgrading legacy JVM-based pipelines into newer, cleaner architectures
• Remapping incoming datasets and rewriting ingestion and transformation pipelines
• Working across SQL Server, JVM applications, and Spark-based workloads
• Contributing improvements to data quality, performance, and maintainability

Tech environment

• Kotlin & Spring Boot for core data processing services
• Python for tooling and automation
• Legacy systems in C# and Scala / Spark
• Exposure to data lakes and large-scale data platforms is a strong plus

What they’re looking for

• Strong JVM background (Kotlin, Java, or Scala)
• Experience building or modernising data pipelines
• Solid understanding of SQL and data processing systems
• Comfortable working in complex, performance-sensitive environments
• Financial markets or trading data experience is beneficial but not essential

6-month initial contract with potential to extend. Onsite by default, with some flexibility for hybrid working.