Legal Engineer

Reporting To: Head of Legal Engineering (working closely with the CEO)

Location: London hybrid / remote (UK-based)

Salary: £35,000–50,000 + Opportunity for equity

Lexical Labs is an innovative legal technology company specialising in AI-driven contract analysis and review. Our mission is to revolutionise the legal sector by automating routine contract tasks, enabling legal professionals to focus on high-value strategic work. We blend cutting‑edge Large Language Models (LLMs) with deep legal expertise to deliver precise, reliable, and insightful data‑driven solutions.

We offer an exciting environment for ambitious individuals passionate about technology, innovation, and transforming the future of legal work.

We’re now hiring a Legal Engineer — a hybrid legal‑and‑technical role at the heart of how we design, build, and deliver our automated contract review systems.

This is a hands‑on, influential role that sits at the intersection of legal practice, product design, and AI implementation.

As Legal Engineer, you’ll help design and refine our automated contract review workflows, build and maintain negotiation playbooks, shape prompts and evaluation datasets for LLMs, and ensure our products genuinely align with how lawyers and in‑house teams actually work.

You’ll work closely with our Head of Legal Engineering, engineers, and founders to:

• Encode legal judgment into scalable, repeatable systems; and
• Bridge the gap between “how lawyers think” and “how machines operate”.

This role is ideal for a lawyer or legal professional who enjoys the technical side of things, is curious about how AI works under the hood, and is excited by the idea of building tools rather than just using them.

• Assist in the design and development of automated solutions for reviewing contracts, identifying risks, and surfacing negotiation positions.
• Analyse existing legal workflows (e.g. intake, review, escalation, approval) to identify where automation can streamline processes and reduce errors.
• Help define and refine issue taxonomies, risk categories, and decision trees that underpin our automated review.

• Develop and maintain tailored contract playbooks that capture positions, fall‑backs, risk ratings, and internal guidelines.
• Work with internal and client teams to keep playbooks current with evolving policies, case law, and commercial strategy.
• Translate playbooks into structures that can be used effectively by LLM‑based systems (e.g. rules, templates, structured data).

• Collaborate with developers to design, test, and refine prompts and workflows for LLMs, ensuring outputs are accurate, consistent, and useful to legal users.
• Experiment with different prompting strategies, instructions, and context formats to reduce hallucinations and capture nuanced legal reasoning.
• Document patterns, edge cases, and best practices so we can scale what works across matters and clients.

• Prepare, label, and curate legal datasets for training and evaluating our systems (e.g. annotated clauses, test contracts, gold‑standard answers).
• Support the design of evaluation pipelines: define what “good” looks like, craft test scenarios, and help measure quality and risk.
• Test new product features end‑to‑end, identify failure modes, and provide structured feedback to the engineering team.
• Help ensure our products stay tightly aligned with the needs of lawyers and contract managers in practice.
• Support product demos and proof‑of‑concepts by preparing realistic example documents, workflows, and playbooks.
• Contribute to user training, documentation, and internal FAQs, helping legal users understand how to get the best from our tools.
• Act as a subject‑matter bridge in client conversations, translating between legal context and technical implementation.

• Legal experience with contracts: Familiarity with commercial contract life cycles and workflows in law firms or in‑house legal teams, including experience drafting, reviewing, and negotiating contracts.
• Workflow and systems…