Knowledge Graph Engineer

About the Position

Playbook is building the Operating Memory for regulated industries. We turn procedural documents into structured, usable data making critical operational knowledge consumable by humans, software systems, and AI agents. This living layer of procedural knowledge is what we call Operating Memory.

We are hiring a Knowledge Graph Engineer to own the production systems behind that translation. You will report directly to our Head of AI and operate as a senior Individual Contributor, collaborating closely with our cross-functional teams.

Responsibilities

• Build and ship the core knowledge representation layer of the platform (ontology-based, structured, deterministic where required)
• Translate regulatory and operational rules into machine-executable logic
• Design and own: data pipelines, APIs, validation logic, and runtime enforcement mechanisms and decide when not to use ML (and replace it with formal logic, constraints, or deterministic systems)
• Use LLMs deliberately for interpretation, assistance, and interface layers; never as an uncontrolled source of truth
• Make and own architectural decisions for the knowledge and enforcement layers (with clear constraints, but real decision authority)
• Own correctness, reliability, and maintainability in production including defining what “correct” means and how it is verified

Requirements

• 5+ years building production systems involving AI, ML, or complex logic
• Strong CS fundamentals (data structures, algorithms, system design)
• Experience in regulated or high-stakes environments (healthcare, pharma, finance, compliance)
• Exposure to: knowledge graphs, ontologies, rules engines, formal logic, symbolic or hybrid AI systems
• Comfort with greenfield systems and long-term ownership
• Willingness to learn novel approaches to knowledge representation (we are building something fundamentally new)

Nice to Have

• Tech environment (indicative, not dogmatic):
  • Python
  • Graph databases / ontology tooling
  • LLMs with a focus on reliability and control
  • AWS

We Offer

• Define the production backbone of a new category at the intersection of enterprise software, regulated operations, and AI infrastructure.
• Foundation: Real influence on the foundation of the company. You will shape the architecture that every future product capability is built on.
• Build from Zero: Real ownership from day one. High ambition, high standards, and a strong bias towards execution - with the runway to ship.
• An emerging category: Work at the intersection of AI, compliance, and enterprise operations - genuinely new ground.
• State-of-the-art hardware: A hardware setup of your choice, designed for deep, focused engineering work.
• Remote-first, high-trust: A culture where execution and impact are what matter - not hours or optics.

About the Company

Playbook is building the Operating Memory for regulated industries. We work with leading global life sciences companies and are building the foundational data model for procedural knowledge in regulated industries. We're a Series A founder-led startup with high ambition, high standards, and a strong bias toward execution.

Why Now

Enterprise AI agents can't run on fragile data pipelines. They need deterministic, auditable, and low-latency infrastructure under the hood.

Think this is your kind of challenge?

Send us your CV, a short note on why you'd be a great fit, and links to anything you've built. We're looking forward to hearing from you.

Apply for this role