KDB Application Technology Lead Analyst (VP)

Citigroup Inc.; Belfast City District; Hybrid; GBP 110,000 - 140,000; Full time

Benefits offered by this job

27 days annual leave

Discretional bonus

Private Medical Care & Life Insurance

Employee Assistance Program

Pension Plan

Paid Parental Leave

Employee discounts

Job summary

Citigroup Inc. is seeking an Applications Development Technology Lead Analyst (KDB Lead Developer) in Belfast to architect, implement, and optimize high-performance data systems for electronic trading and analytics.

You will mentor engineers, guide technical direction, and collaborate with traders, researchers, and infrastructure teams to deliver low-latency time-series solutions.

Qualifications

• Hands-on development with KDB+/q in low-latency trading or market data.
• Expertise in building scalable, fault-tolerant tick architectures.
• Experience with real-time and historical time-series databases.

Responsibilities

• Lead end-to-end design and maintenance of KDB+ architectures (TP, RDB, HDB, GW).
• Set best practices for q code, memory management, and partitioning.
• Drive collaboration with traders, risk managers, and researchers.
• Develop high-throughput feedhandlers and APIs interfacing with Kafka/Solace.

Skills

KDB+/q mastery

Python

C/C++

Linux/Unix

Java interface with KDB+

Cloud platforms

CI/CD

Education

Bachelor's degree in CS/Engineering

Tools

Kafka

Solace

LBM/29West

Docker

Kubernetes

Job description

The Applications Development Technology Lead Analyst (KDB Lead Developer) is a senior-level technical leadership role responsible for architecting, establishing, and implementing high-performance, low-latency tick and time-series data systems. This role leads the design, development, optimization, and support of real-time and historical KDB+/q architectures supporting Electronic Trading, Market Data, Quantitative Research, Risk, and Analytics.

The ideal candidate will serve as the subject matter expert (SME) in KDB+/q, guiding technical direction, mentoring engineers, and collaborating closely with business stakeholders, quantitative researchers, traders, and infrastructure teams.

Key Responsibilities

Architecture, Design & Technical Leadership

• Lead the end-to-end design, implementation, and maintenance of scalable, fault-tolerant KDB+ architectures, including real-time tickerplants (TP), Real-Time Databases (RDB), Historical Databases (HDB), Real-Time Subscribers (RTS), Intraday Databases (IDB), and Gateway (GW) query routers.
• Define and enforce best practices for q code development, schema design, memory management, data partitioning/splaying, query optimization, and indexing/attributes (p#, g#, s#, u#).
• Serve as the primary technical authority for KDB+ platform engineering, ensuring architectural alignment with enterprise technology blueprints, cloud adoption strategies, and compliance standards.
• Partner with Quantitative Analysts, Trading Desks, and Risk Managers to translate complex quantitative models and business requirements into highly optimized time-series calculations and analytical engines.

Development & Integration

• Design and build high-throughput feedhandlers, APIs, and microservices interfacing KDB+ with upstream messaging fabrics (e.g., Kafka, Solace, LBM/29West, ZeroMQ) and downstream consumer platforms.
• Develop high-performance C/C++ or Python shared libraries (embedPy, PyQ, C API) for real-time analytics, machine learning integration, or proprietary calculation engines.
• Oversee the migration, integration, or hybrid deployment of KDB+ on-premises and in cloud environments (e.g., AWS, GCP, KX Insights).

Performance Engineering & Stability

• Conduct deep profiling, capacity planning, and latency/memory optimization across high-volume market and transactional data streams.
• Implement robust Disaster Recovery (DR), business continuity (COB), high-availability (HA), and automated failover mechanisms across distributed multi-region environments.
• Develop and institutionalize automated testing frameworks (unit, regression, and load testing) and modern CI/CD release pipelines for KDB+ code and data schemas.

People Leadership, Governance & Controls

• Lead, mentor, and coach mid-level and junior KDB developers; conduct rigorous code reviews and foster a culture of technical excellence.
• Supervise work allocation, sprint deliverables, and release management across distributed agile development pods.
• Appropriately assess risk when business decisions are made, demonstrating particular consideration for the firm’s reputation and safeguarding the firm, its clients, and assets by driving compliance with applicable laws, rules, and regulations, adhering to Policy, applying sound ethical judgment, and managing control issues with transparency.

Qualifications & Skill Set

Core Technical Experience

• Proven hands-on experience in application software development with a specialized focus on KDB+/q in a high-volume, low-latency financial trading or market data environment.
• Deep KDB+/q Mastery:
  • Expert proficiency in writing idiomatic, vectorized q code and advanced complex event processing (CEP).
  • Proven track record designing and tuning full-stack KDB+ Tick architectures (Tickerplant, Chained Tickerplant, RDB, HDB, CEP, Gateway/Query Routers).
  • Advanced knowledge of IPC, multi-threading (-s), worker processes, memory allocators, compression algorithms, and partitioned database maintenance.
• Languages & Frameworks:
  • Strong proficiency in Python (including data science stack: Pandas, NumPy, and integration tools like embedPy, PyKX, or qPython).
  • Solid understanding of Java interface programming with KDB+ and platform
  • Familiarity with enterprise messaging middleware (Kafka, Solace, Tibco EMS/LBM).
• Operating Systems & Infrastructure:
  • Expert-level proficiency in Linux/Unix operating systems, shell scripting (Bash), and system-level performance tuning (CPU affinity, NUMA, I/O schedulers, NVMe/SSD storage optimization).
• DevOps, Tooling & Modernization:
  • Familiarity with CI/CD pipelines (Git, Teckton, Harness, GitHub, Artifactory etc).
  • Knowledge of containerization and orchestration (Docker, Kubernetes/OpenShift) as applied to KDB+ workloads is a strong plus.

Business & Domain Knowledge

• Strong knowledge of Capital Markets, Electronic Trading, and Financial Instruments (Equities, FX, Fixed Income, Rates, Commodities, or Derivatives).
• Familiarity with Market Data protocols (L1/L2/L3 order books, FIX, ITCH, OUCH, BBO/NBBO) and quantitative analytics (TCA, VWAP/TWAP, volatility surfaces, PnL, pre/post-trade risk).

Leadership & Soft Skills

• Proven leadership skills with demonstrated experience managing project workstreams and coaching technical teams.
• Excellent problem-solving, interpretive thinking, and analytical capabilities under time-sensitive constraints.
• Strong written and verbal communication skills with the ability to articulate complex technical concepts to non-technical stakeholders, traders, and senior management.

This job description provides a high-level review of the types of work performed. Other job-related duties may be assigned as required.

What we’ll provide you

By joining Citi, you will not only be part of a business casual workplace with a hybrid working model (up to 2 days working at home per week), but also receive a competitive base salary (which is annually reviewed), and enjoy a whole host of additional benefits such as:

• 27 days annual leave (plus bank holidays)
• A discretional annual performance related bonus
• Private Medical Care & Life Insurance
• Employee Assistance Program
• Pension Plan
• Paid Parental Leave
• Special discounts for employees, family, and friends
• Access to an array of learning and development resources

Visit our Global Benefits page to learn more.

Alongside these benefits Citi is committed to ensuring our workplace is where everyone feels comfortable coming to work as their whole self, every day. We want the best talent around the world to be energized to join us, motivated to stay and empowered to thrive.

#LI-AP2

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Job Family Group:

Technology

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Job Family:

Applications Development

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Time Type:

Full time

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Most Relevant Skills

Please see the requirements listed above.

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Other Relevant Skills

For complementary skills, please see above and/or contact the recruiter.

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