Paul James O'Toole

Lead Software Engineer at MarketAxess

Atlanta Metropolitan Area

About

Experienced engineering leader with a proven record of building scalable platforms, leading high-performing teams, and delivering production systems that drive business impact across finance, federal, and healthcare sectors. Currently a Lead Software Engineer at MarketAxess, where we architect and deliver distributed, event-driven systems powering high-throughput market data processing and low-latency bond trading. My technical background spans cloud-native microservices, real-time APIs, event streaming, service orchestration, CI/CD infrastructure, and machine learning systems. I pair deep backend knowledge with a strong product mindset—consistently aligning engineering outcomes with business goals. I began my career in computational bioengineering research at Notre Dame, applying image analysis and modeling to study cellular signaling in cancer formation. That foundation in quantitative problem-solving led to a career in software engineering, alongside earning an M.S. in Computer Science from Georgia Tech while working full time.

Experience

  • MarketAxess (Remote)
    • Lead Software Engineer
      Jan 2025 - Present · 1 yr 6 mos

      Led an engineering team delivering scalable, event-driven systems for fixed-income trading. Oversaw critical initiatives including cloud migration, platform expansion, and system integrations supporting significant business growth.

    • Senior Software Engineer
      Nov 2021 - Dec 2024 · 3 yrs 2 mos

      Designed and built distributed services and infrastructure supporting fixed-income trading workflows.

  • Accenture Federal Services (Full-time · 1 yr 10 mos)
    • Senior Software Engineer
      May 2021 - Nov 2021 · 7 mos

      Led development efforts modernizing logistics systems for a major federal agency, including hybrid cloud integrations and CI/CD automation. Delivered backend systems and infrastructure supporting large-scale SAP environments.

    • Software Engineer
      Feb 2020 - May 2021 · 1 yr 4 mos

      Built production systems to deploy and serve machine learning models at scale across distributed edge infrastructure for a federal client. Focused on microservices, model orchestration, and continuous delivery for secure federal operations.

  • Application Support Engineer at Epic
    Sep 2018 - Dec 2019 · 1 yr 4 mos

    Worked with large healthcare clients to enhance patient engagement platforms through custom development, technical troubleshooting, and cross-functional coordination. Supported operational strategy, compliance, and platform upgrades.

  • Software Engineer at University of Notre Dame
    Jun 2015 - May 2018 · 3 yrs

    Contributed to research focused on the quantitative analysis of pattern formation, growth, and regeneration in epithelial tissue in Jeremiah Zartman's Bioengineering lab at Notre Dame.

  • Summer Intern at Memorial Sloan Kettering Cancer Center
    Jun 2013 - Aug 2013 · 3 mos

    Contributed to research focused on the genetics of Liposarcoma in Dr. Andrew Koff's Molecular Biology lab at Memorial Sloan-Kettering Cancer Center.