Principal ML Engineer

Realm.Security, Inc

Realm.Security, Inc

Software Engineering, Data Science

Posted on May 2, 2026

About Us: We are a Series-A cybersecurity startup, helping SOC teams manage their distributed security data by leveraging cutting-edge AI and streaming technologies. Our Security Data Fabric normalizes, enriches, and correlates security data from dozens of disparate sources in real-time. This creates the high-fidelity data foundation needed to power next-generation AI-SIEMs, while reducing customer data costs through intelligent filtering. We are seeking a Principal ML Engineer to develop AI/ML product features that power our pipeline.

Role Overview: We are seeking a hands-on Principal ML Engineer to build production-level solutions that empower cybersecurity teams. You will innovate with data exploration, model training, and system design to produce software solutions that automate the challenges SOC teams face as they manage their security data. Your work will extend the capabilities of our cutting-edge Data Fabric technology, and make managing complex security pipelines simple, so that teams can focus on catching attackers and keeping their businesses safe.

Key Responsibilities:

  • AI/ML Innovation: Develop new machine learning models and software algorithms to address complex product requirements.
  • Project Ownership: Take ownership of project deliveries and stay connected with Product requirements.
  • Development: Leverage Python to develop, debug, and optimize software systems that integrate AI/ML into the product.
  • Big Data Analysis: Derive insights from large datasets to identify opportunities for model and algorithm development.
  • Model Selection: Choose the right technique to address the problem, balancing performance and speed of delivery.
  • GenAI and Agents: Solve problems with unstructured text data using LLM and agentic solutions.
  • Collaboration: Partner with Engineering and Security experts to understand the domain, and iterate rapidly to a solution.
  • Learning Champion: Continually learn about new technologies and techniques in AI/ML, and champion them within the company.

Qualifications:

Experience:

  • Masters degree in Computer Science, STEM, or related field; PhD preferred.
  • 10+ years of hands-on experience in Data Science, ML Engineering, or a related role.

Technical Skills:

  • Proven expertise in developing machine learning and AI solutions
  • Solid understanding of mathematical and statistical principles applied to ML
  • Hands-on use of ML frameworks such as PyTorch or Tensorflow
  • Broad experience with neural networks, classical ML, and large language models
  • Strong Python development skills at a production-level, including testing and deployment considerations
  • Proficiency in software algorithms and data structures
  • Experience working with large datasets using tools like Polars and Spark; streaming expertise preferred
  • Experience with designing scalable and robust ML systems
  • Proficiency with Linux and Cloud environments
  • Rust programming is a plus

Soft Skills:

  • Excellent problem-solving skills and attention to detail, with a passion for learning new technologies and innovating.
  • Effective communication and collaboration skills, with the ability to work well in a fast-paced, dynamic startup environment.

Benefits:

  • Fully remote or hybrid opportunity with Boston office.
  • We foster a collaborative and inclusive culture, prioritizing sustainable team growth and a strong commitment to work-life balance.
  • Opportunity to join an early-stage company and make a significant impact in shaping and improving our core infrastructure.
  • Competitive salary and equity package.
  • Comprehensive health, dental, and vision insurance plans.

Join Us: If you’re an experienced ML Engineer with a passion for security and innovation, we look forward to learning more about you. Let’s build something great together. Apply now!