Senior Staff Machine Learning Engineer

ServiceNow; York and North Yorkshire; On-site; GBP 120,000 - 180,000; Full time

Benefits offered by this job

Generous family leave

Matched donations

Annual learning stipends

Flexible PTO

Competitive retirement plan

Paid volunteer time

Job summary

ServiceNow is seeking a Senior Staff Engineer to own the end-to-end architecture of a novel exploitability engine in security and risk engineering. You will set technical direction, make defensible calls, and multiply the engineers around you.

You will lead cross-team architecture reviews with product, SecOps, and R&D, establishing guardrails for AI-powered systems while delivering reliable, scalable solutions in production.

Qualifications

• Experience evaluating AI safety, governance, or policy guardrails.
• Track record owning architecture across large systems or multiple teams.
• Technical leadership and mentorship that moves teams through influence.
• Demonstrated experience as technical owner or lead for a major system.
• Strong programming in Python and/or Java, Go, or TypeScript.

Responsibilities

• Lead zero-to-one work at production scale across security harness architecture.
• Define architectural direction and drive decisions with product and SecOps partners.
• Mentor engineers and raise the engineering bar across incubation efforts.
• Manage calibration, validation, and guardrails for AI-driven predictions.

Skills

Python

Java/Go/TS

Distributed systems

Cloud-native

Graph analytics

Probabilistic modeling

Agentic AI

Security products

Tech leadership

Architecture direction

Zero-to-one

Mentorship

Education

Bachelor’s/Master’s in CS/AI/ML or related

Tools

Claude Code

Codex

Cursor

Windsurf

Job description

• The Security and Risk Engineering organization builds scalable, AI-powered security solutions that reduce risk and protect ServiceNow and its customers
• We value AI-first thinking, clean architecture, intuitive experiences, and a culture of continuous learning
• This is a zero-to-one incubation. We’re building a new class of exposure analysis that ranks security work by exploitability—where an attacker could realistically get in—rather than raw severity. The architecture is evolving, and this role helps define what good looks like
• As a Senior Staff Engineer, you own the architecture of an security harness with novel exploitability engine end to end, and you’re accountable for the decisions that shape everything downstream
• You set technical direction, make the hard calls defensible, and multiply the engineers around you
• The end-to-end architecture of the exploitability engine—from evidence ingestion and entity resolution, through the attack-path probability core and choke-point ranking, to the validation loop that keeps predictions honest
• The decisions that cascade through the system: calibrated probability versus ordinal rank, identity as a first-class graph edge, assume-breach seeding, and how the most critical assets are defined. These are model-shaping calls, not implementation details
• The probabilistic ranking core: edge-traversal probability, guided path search with hop and likelihood limits, correlated-control-failure modeling, and honest uncertainty bands
• The calibration and validation loop—canaries, purple-team and incident replay, calibration measured by zone and vector—that turns modeled weights into evidence rather than opinion
• Make-or-break metrics as first-class engineering targets, starting with entity-resolution accuracy and calibration quality
• The build-on strategy—extending the existing portfolio rather than rebuilding it, and knowing precisely what to reuse and what must be net-new
• Lead zero-to-one work at production scale: turn an ambiguous, novel problem into a reliable system other teams build on, and set the bar where no precedent exists
• Drive technical direction across architecture, design, and code reviews, and raise the engineering bar across the incubation
• Mentor senior engineers and lead by influence, not title
• Partner with product, security R&D, SecOps to turn customer problems into architecture, and translate that architecture into decisions leaders can act on
• Establish AI safety, security, governance, and guardrails for agentic systems running in production

Benefits

• Generous family leave
• Matched donations
• Annual learning stipends
• Flexible PTO
• Competitive retirement plan
• Paid volunteer time

• Experience with AI evaluation, safety, governance, or policy guardrails is a plus
• A track record of owning architecture across a large system or multiple teams, with deep experience operating production-quality software
• Technical leadership and mentorship that moves teams through influence
• Demonstrated experience as the technical owner or lead for a major system or across teams
• Strong programming experience in Python and/or Java, Go, or a similar language
• Cybersecurity or security-product experience, or familiarity with modern security architectures and operations, is strongly preferred
• Command of distributed systems, APIs, cloud-native development, and data or graph systems
• Hands-on depth in both agentic and LLM systems and probabilistic or ML-driven scoring—graph modeling, calibration, search and optimization, or risk and probability engineering
• Proven zero-to-one at scale: you’ve taken an ambiguous problem to a reliable production system that others depend on
• Applied interest in security problems—attack-path analysis, vulnerability management, identity security, threat intelligence, or detection and response is strongly preferred
• Bachelor’s or Master’s degree in Computer Science, Artificial Intelligence, Machine Learning, or a related technical discipline, or equivalent practical experience
• Expert-level Python, and/or Java, Go, or TypeScript
• Depth building AI/ML-powered production systems; probabilistic modeling, graph analytics, or calibration and evaluation is a strong plus
• Modern AI experience: LLMs, RAG, embeddings, vector search, agentic harness and workflows, model evaluation, or AI observability
• 10+ years of software engineering experience, including leading the design and delivery of complex production systems
• Experience with AI-assisted development tools and coding agents such as Claude Code, Codex, Cursor, or Windsurf is a plus
• Cloud-native technologies, distributed systems, APIs, databases, and scalable architectures
• The judgment to make consequential architecture decisions under uncertainty, and make them defensible to engineers and executives alike.