Principal Software Engineer

Fidelity Investments is a privately held, Boston-headquartered financial services company providing investing, trading, retirement, wealth management, brokerage, workplace benefits, custody and clearing, and digital-asset services.

Maintainer signals as of 9/25/2026

Boston, Massachusetts, United States
About Fidelity Investments

Fidelity serves individual investors, employers, wealth-management firms, institutions, innovators, and charitable donors through diversified financial-services businesses. Current offerings include brokerage and trading, mutual funds and exchange-traded products, retirement and workplace savings, financial planning and advice, wealth management, institutional custody and clearing, and crypto/digital-asset products.

View jobs by Fidelity Investments

Skills

Candidate Availability

Required and preferred rules are kept separate and reflect the wording in the original posting.

About the Role

You will lead the hands-on design and development of resilient trading infrastructure. You will optimize KDB databases and q analytics, develop Python AI and quantitative models, build backtesting frameworks, integrate models into production pipelines, and mentor engineers while supporting production systems.

Requirements

  • Bachelor's degree in Mathematics, Computer Science, Engineering, Information Technology, or equivalent.
  • 10 years of professional experience in quantitative finance or trading systems.
  • Advanced KDB/q proficiency, including time-series modeling, high-performance querying, joins, and analytics.
  • Python skills for quantitative analysis, AI and machine-learning model development, and KDB integration.
  • Experience with large-scale, high-frequency, or noisy datasets.
  • Git, testing, and modular software design experience.
  • Experience with AI developer-assist tools such as GitHub Copilot.
  • Experience with GitHub, Maven, Jenkins, Artifactory, uDeploy, and CI/CD tools.
  • AWS or other cloud platform experience.
  • Familiarity with Java, Linux, shell scripting, and production support.

Responsibilities

  • Design, develop, and optimize KDB databases and q analytics for trading and market data.
  • Develop Python-based AI and quantitative models for research, prediction, classification, and signal generation.
  • Apply machine learning to time-series data.
  • Build research and backtesting frameworks using historical data.
  • Translate quantitative and machine-learning research into production systems.
  • Integrate AI models into real-time and batch pipelines.
  • Optimize analytics and model evaluation for performance, stability, and scalability.
  • Collaborate with quantitative, product, and engineering partners on model deployment and monitoring.
  • Lead technical design, mentor engineers, and support production systems and on-call rotations.

Benefits

  • Comprehensive health care coverage.
  • Emotional well-being support.
  • Retirement benefits.
  • Paid time off.
  • Parental leave.
  • Charitable giving employee match program.
  • Student loan repayment.
  • Tuition reimbursement.