Full-Time

Citadel X – Production Engineer

Posted on 9/27/2025

Citadel Securities

Citadel Securities

1,001-5,000 employees

Global market maker delivering liquidity

Compensation Overview

$150k - $300k/yr

+ Discretionary incentive compensation program

New York, NY, USA

In Person

Category
DevOps & Infrastructure (3)
, ,
Required Skills
Kubernetes
Python
JavaScript
React.js
Java
Postgres
Linux/Unix
Requirements
  • Experience with Linux systems, shell scripting
  • Experience with Kubernetes, cloud-based infrastructure, distributed systems, and large-scale infrastructure management
  • Experience with Java (JVM, Heap management)
  • Experience with databases such as Postgres
  • Proficiency in at least one programming language (e.g., Python, Java) and strong scripting skills. Familiarity with Q/KDB a plus
  • Experience with monitoring, logging, and automation frameworks.
  • Ability to analyze complex systems, identify failure modes, and design solutions that improve resiliency.
  • Strong problem-solving skills, with the ability to perform under pressure in mission-critical environments.
  • Excellent communication and collaboration skills, with the ability to influence and partner effectively across teams.
  • Prior experience in low-latency, high-performance, or financial technology environments is a plus.
  • Experience with Front-End technologies (React, Javascript) – a plus!
  • Bachelor’s degree
Responsibilities
  • Build, operate, and maintain critical production infrastructure that supports trading and research systems.
  • Partner with engineering teams to design systems that are scalable, resilient, and observable from the ground up.
  • Troubleshoot complex issues across the technology stack—application, systems, networks, and storage—under time-sensitive conditions.
  • Develop automation to reduce manual effort, improve reliability, and accelerate incident response and recovery.
  • Continuously monitor performance, reliability, and capacity, proactively identifying opportunities for improvement.
  • Establish best practices for deployment, change management, incident management, and operational excellence.
Desired Qualifications
  • Prior experience in low-latency, high-performance, or financial technology environments is a plus.
  • Experience with Front-End technologies (React, Javascript) – a plus!
  • Familiarity with Q/KDB a plus

Citadel Securities is a global market maker that provides liquidity and trading services to institutional clients in equities, options, and FICC markets. It uses advanced technology and data analytics to place and manage bid-ask quotes, execute trades, and optimize order routing, earning a small margin on each trade and charging fees for services. Its products and services help clients meet liquidity needs with low-cost, efficient execution. The company distinguishes itself by aiming for the fairest, most transparent, and open markets, continually reinvesting in technology and expertise to improve market efficiency and transparency. The goal is to bridge the financial markets with the real economy by creating reliable liquidity and transparent trading environments.

Company Size

1,001-5,000

Company Stage

Growth Equity (Venture Capital)

Total Funding

$1.2B

Headquarters

Miami, Florida

Founded

2002

Simplify Jobs

Simplify's Take

What believers are saying

  • Hired Rachel Underhill from BNP Paribas to bolster fixed income ETF sales in New York.
  • Appointed Scott Rubner from Goldman Sachs as head of equity strategy in July 2025.
  • Relocated headquarters to Miami's 830 Brickell Plaza to attract talent in financial hub.

What critics are saying

  • CFO Andrew Philipp defects to Schonfeld as co-president in September 2026, eroding leadership.
  • Jane Street captures 15-20% of retail flow with superior latency, slashing spread revenues.
  • DOJ antitrust probe into 40% equities share forces divestitures within 18-24 months.

What makes Citadel Securities unique

  • Citadel Securities provides one-third of U.S. market liquidity as NYSE's largest designated market maker.
  • Firm leads global ETF trading with block-sized liquidity across equities and fixed income.
  • Launches 24/5 overnight liquidity via three venues starting June 2026.

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Benefits

Health Insurance

Life Insurance

401(k) Retirement Plan

Performance Bonus

Growth & Insights and Company News

Headcount

6 month growth

0%

1 year growth

0%

2 year growth

1%
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