Principal Active Defense Engineer

Workday, Inc.; Reston, Northern (VA, KY); Hybrid; USD 167,000 - 300,000; Full time

Job summary

Workday, Inc. is seeking a Principal Active Defense Engineer to set the technical direction for threat detection and lead multi-system initiatives from concept to production.

This hands-on role emphasizes detections-as-code, CI/CD tooling, and mentor-mentee growth across the security engineering team. You will apply AI-assisted analysis and agents to detection work, partner with incident response and security tooling, and shape the future of Workday's Active Defense platform from Reston, VA.

Qualifications

• 10+ years in detection or security engineering at production scale.
• Experience leading multi-system initiatives as an individual contributor.
• Proficiency in Python, Java, Kotlin, Scala, or JavaScript for detection/automation.
• Experience architecting a detections-as-code pipeline or production data pipeline.
• Experience applying generative AI or AI agents in security engineering.
• Experience with SIEM platforms like Splunk and cloud security.

Responsibilities

• Set the technical direction for the detection portfolio and platform.
• Serve as the senior reviewer for infrastructure changes and complex detections.
• Lead large initiatives from concept to production, including playbooks and validation.
• Advance the detections-as-code lifecycle, CI/CD tooling, and curated datasets.
• Mentor engineers through design and code reviews to scale delivery.
• Determine where AI, agents, and automation belong in detection work.

Skills

Detection engineering

Technical leadership

Software development

Detections-as-code

AI in security

Cloud platforms

Tools

Splunk

CI/CD tooling

AI-assisted tools

Job description

Your work days are brighter here. We’re obsessed with making hard work pay off, for our people, our customers, and the world around us. As a Fortune 500 company and a leading AI platform for managing people, money, and agents, we’re shaping the future of work so teams can reach their potential and focus on what matters most. The minute you join, you’ll feel it. Not just in the products we build, but in how we show up for each other. Our culture is rooted in integrity, empathy, and shared enthusiasm. We’re in this together, tackling big challenges with bold ideas and genuine care. We look for curious minds and courageous collaborators who bring sun-drenched optimism and drive. Whether you're building smarter solutions, supporting customers, or creating a space where everyone belongs, you’ll do meaningful work with Workmates who’ve got your back. In return, we’ll give you the trust to take risks, the tools to grow, the skills to develop and the support of a company invested in you for the long haul. So, if you want to inspire a brighter work day for everyone, including yourself, you’ve found a match in Workday, and we hope to be a match for you too.

About the Team

Our Active Defense team is a group of highly skilled and dedicated professionals who are passionate about protecting our organization from cyber threats. We source, evaluate, and analyze both internal and external data, providing critical insight to a variety of security and business teams. We use emerging and relevant intelligence to test our defenses rapidly. We perform detailed analysis while meeting the challenge to scale to the business needs. We are a core function of the overall Cyber Defense organization at Workday that helps keep the company and its customer data safe every day. Our team members have a strong background in cybersecurity, data analysis, AI and machine learning, and detection engineering. We use innovative tools and technologies to analyze and visualize data, including Splunk, Spark, Python, and AI-assisted analysis and automation tools. We value teamwork and collaborate closely with other security teams to ensure that our organization stays ahead of emerging cyber threats. We are committed to continuous learning and professional development, and regularly attend industry conferences and training sessions to stay up to date on the latest trends and best practices in security analytics.

About the Role

This role is the senior technical anchor for Active Defense. As a Principal Active Defense Engineer, you will set the technical direction for how Workday detects threats, and you will be the engineer the team looks to when a problem is ambiguous, spans several systems, or has no obvious owner. The breadth here is real. Our work runs from translating threat intelligence into new detections, through the quality and fidelity of the alerts we hand to incident response, to the detections-as-code pipeline, curated datasets, and CI/CD tooling that all of it depends on. We also serve as the subject matter experts other teams come to for audits, coverage questions, and platform decisions. You will be expected to operate across that whole surface rather than in one corner of it. The engineers who do best in this seat tend to come from a strong software, platform, or data engineering foundation applied to security, rather than from a purely analytical security path. You will lead large initiatives from concept to production with little direction, and you will decide how we apply AI‑assisted analysis, automation, and agents to detection work. This is a team early in its growth, so the standards you set will be adopted broadly and quickly, and raising the technical ceiling of the engineers around you through mentorship, design review, and the standard your own work sets is a core part of the job. This is a hands‑on engineering role rather than a people management role.

Responsibilities

• Set the technical direction. Own the architecture decisions, detection methodology, and design standards for the detection portfolio and the platform it runs on.
• Be the review authority. Serve as the senior reviewer for infrastructure changes and complex detections, so that design and code review is a fast path for the team rather than a queue.
• Lead large initiatives through to live operation. Take ambiguous problems from concept all the way to running in production, including the validation, documentation, and response playbook that make an alert worth acting on.
• Build for reuse. Advance the detections-as-code lifecycle, CI/CD, validation tooling, and curated datasets, turning one-off solutions into patterns the whole team adopts.
• Raise the technical ceiling of the team. Mentor engineers through design review, code review, and pull request feedback so that judgment and delivery scale beyond any one person.
• Lead how we apply AI. Determine where agents, automation, and generative tooling belong in authoring, validating, and tuning detections, and where they do not.
• Own detection quality. Drive coverage, fidelity, and noise reduction so that the alerts reaching our incident responders are worth their attention.
• Represent detection engineering across Workday. Partner with incident response, threat intelligence, security tooling, audit, and platform teams, and serve as the expert voice on detection coverage and capability.
• Shape what comes next. Evaluate emerging detection approaches, platforms, and vendors, and bring in what measurably improves outcomes.

About You

Basic Qualifications

• Depth in detection engineering: 10+ years in software, platform, or security engineering, including significant time building and operating detection or security capabilities at production scale.
• Technical leadership as an individual contributor: Experience setting technical direction, leading complex multi-system initiatives, and raising the level of the engineers around you through design and code review, without managing people.
• Software development expertise: Experience in a general-purpose programming language such as Python, Java, Kotlin, Scala, or JavaScript, used to build detection logic, tooling, and automation.
• Detection platform ownership: Experience architecting a detections-as-code pipeline, detection platform, or production data pipeline that other engineers build on, rather than working within one someone else built.
• AI-assisted engineering judgment: Experience applying generative AI, conversational AI, or AI agents to security engineering work, including cases where you concluded the AI-assisted approach was the wrong one.
• Platform and cloud breadth: Experience with SIEM platforms such as Splunk, and with developing, securing, and monitoring applications in public cloud environments.

Other Qualifications

• Production engineering discipline: Experience with automated testing, validation, and deployment for detection content, not only version control.
• Threat-informed detection: Experience translating threat intelligence, adversary techniques such as those in MITRE ATT&CK, and incident learnings into durable detections, and verifying that those detections fire.
• Adaptive detection analytics: Familiarity with behavioral baselines, entity-level context, anomaly detection, or risk-based alerting.
• Cross-team technical leadership: Experience serving as the subject matter expert for partner teams, audits, and compliance or customer inquiries.
• Program judgment: Proven ability to run several complex technical projects at once across competing priorities and ongoing operations.
• Communication: Strong communication skills and the ability to present technical information to a non-technical audience.
• Continuous learning: Enthusiasm for emerging work in security, data science, and machine learning, with the judgment to know what is worth adopting.
• Relevant certifications or training such as SANS or CISSP are useful but not required.

Workday Pay Transparency Statement

The annualized base salary ranges for the primary location and any additional locations are listed below. Workday pay ranges vary based on work location. As a part of the total compensation package, this role may be eligible for the Workday Bonus Plan or a role-specific commission/bonus, as well as annual refresh stock grants. Each candidate’s compensation offer will be based on multiple factors including, but not limited to, geography, experience, skills, job duties, and business need, among other things.

Primary Location: USA.VA.Reston Additional US Location(s) Base Pay Range: $167,200 USD - $300,000 USD

Our Approach to Flexible Work

With Flex Work, we’re combining the best of both worlds: in-person time and remote. Our approach enables our teams to deepen connections, maintain a strong community, and do their best work. We know that flexibility can take shape in many ways, so rather than a number of required days in‑office each week, we simply spend at least half (50%) of our time each quarter in the office or in the field with our customers, prospects, and partners (depending on role). This means you'll have the freedom to create a flexible schedule that caters to your business, team, and personal needs, while being intentional to make the most of time spent together. Those in our remote home office roles also have the opportunity to come together in our offices for important moments that matter.

Equal Opportunity & Accommodations

Pursuant to applicable Fair Chance law, Workday will consider for employment qualified applicants with arrest and conviction records. Workday is an Equal Opportunity Employer including individuals with disabilities and protected veterans. Workday is committed to providing reasonable accommodations for qualified individuals during our application process, in order to perform one or more essential functions of their job, as well as regarding the use of AI tools for employment decision-making to any degree. Workday prohibits taking adverse action against any candidate or employee for reporting a possible violation of this policy, requesting one or more work accommodations, exercising a privacy right, or cooperating in an investigation in accordance with applicable law. Any employee who retaliates against a candidate or employee for doing so may be subject to disciplinary action, up to and including termination of employment, to the fullest extent allowable under applicable law. If you require a reasonable accommodation, you may email [e-mail], as far in advance as possible. We do not accept resumes from headhunters, placement agencies, or other suppliers that have not signed a formal agreement with us. Workday is a proud equal opportunity workplace. Individuals seeking employment at Workday are considered without regards to age, ancestry, color, gender (including pregnancy, childbirth, or related medical conditions), gender identity or expression, genetic information, marital status, medical condition, mental or physical disability, national origin, protected family care or medical leave status, race, religion, sexual orientation, military or veteran status, or any other characteristic protected by federal, state, or local laws.