Quantitative Developer – Data Infrastructure

Millennium; Dublin; On-site; EUR 120,000 - 180,000; Full time

Job summary

Millennium, a global investment firm, is seeking a senior data platform engineer to own and extend its research data platform. You will work on petabyte-scale datasets, optimize storage and compute performance, and collaborate with trading, research, and engineering teams in Dublin and across locations.

Responsibilities include building robust storage layers with Arrow/Parquet/Delta Lake, ensuring high throughput, low latency, and strong production quality through CI/CD and testing.

Qualifications

• 6+ years of kdb+ and systems engineering in a quantitative finance setting.
• Bachelor’s degree in CS, math, physics, or financial engineering.
• Strong kdb+/q skills for platform development and data formats knowledge.
• Proficient with Git, Unix/Linux, Bash and CI/CD practices.
• Ability to optimize correctness, latency, throughput, and cost.
• Experience collaborating across cross-functional teams.

Responsibilities

• Own and extend the internal data platform that stores petabytes of research and production data
• Develop and enhance core storage capabilities with Arrow-backed formats and replication across AWS and on‑prem
• Drive throughput and latency improvements across read and write paths
• Design for concurrency in the distributed compute layer with thousands of readers
• Write, test, document, and maintain code with CI/CD and testing
• Partner with team members on platform direction and architecture
• Collaborate with compute and research teams to meet evolving needs

Skills

kdb+/q

Systems engineering

Distributed storage

C++

Git / Unix / Linux

CI/CD practices

Education

Bachelor’s degree in Computer Science, Mathematics, Physics, Financial Engineering, or related field

Tools

Arrow

Parquet

Delta Lake

S3

PyKX

Database internals

Job description

About Millennium

Millennium is a global, diversified alternative investment firm, founded in 1989. Defined by evolution, innovation and focus, Millennium’s mission is to deliver results for our investors. Our people are empowered with both independence and support: the autonomy to pursue ideas with conviction and the backing of a global network committed to collaboration, disciplined risk management and continuous learning. With opportunities to deepen expertise and accelerate development, talent at Millennium is equipped to adapt, evolve and build lasting impact over time. Discover how transformative growth accelerates impact.

Meet the Team

The Execution Services team supports trading across products and geographies, with a focus on execution quality, trading efficiency, and the tools that help portfolio managers make informed decisions. Within this group, Central Liquidity Strategies develops and operates trading capabilities that support internal liquidity solutions across the platform. The team works at the intersection of quantitative research, engineering, and production infrastructure, building the systems and data foundations that support evolving trading and compute needs.

What You\'ll Do

• Own and extend the internal data platform that stores petabytes of research and production data


• Develop and enhance core storage capabilities, including Arrow-backed columnar formats, replication and tiering across AWS and on-prem environments, high-concurrency APIs, and delta-style append and reconciliation semantics


• Drive throughput and latency improvements across read and write paths, with a focus on correctness, performance, and production reliability


• Design for the concurrency demands of the distributed compute layer, including workloads that generate thousands of concurrent readers


• Write, support, maintain, and test code using strong engineering practices, including unit testing, integration testing, documentation, automation, and CI/CD workflows


• Partner with team members on the direction, design, and architecture of the platform


• Collaborate closely with compute and research teams to ensure the storage layer continues to meet evolving platform and user needs

What You Bring

• 6+ years of kdb+ and systems engineering experience in a quantitative finance environment, with a strong track record of delivering and operating production data platforms at scale


• Bachelor’s degree in Computer Science, Mathematics, Physics, Financial Engineering, or a related field


• Strong kdb+/q skills for platform development and a deep understanding of columnar data formats, distributed storage systems, and high-throughput I/O


• Strong working knowledge of Git, Unix/Linux, Bash, and modern CI/CD practices


• Sound systems judgment, with the ability to evaluate tradeoffs across correctness, latency, throughput, and cost


• Confidence making design decisions that shape long-term platform architecture


• Strong communication skills and the ability to work effectively in a collaborative team environment


• Experience with Apache Arrow, Parquet, Delta Lake, S3 and cloud storage, PyKX, C++, and/or database internals is a plus