We’re hiring!
AI Engineer
Design, build, and ship the AI-powered features at the heart of Lexapar
Description
We are seeking an AI Engineer to design, build, and ship the AI-powered features that sit at the heart of the Lexapar platform. A core part of this role is building and owning the model harnesses that let the team develop, test, and compare AI systems with confidence with the evaluation suites, agentic/tool-use scaffolding, and production instrumentation that turn frontier model capability into reliable, shippable features. You will work closely with product, engineering, and legal domain experts to translate real legal workflows into AI-driven product experiences that meet the accuracy and reliability bar the profession demands.
What you’ll do
Model Harness Development: Build and maintain the harnesses that power model development at Lexapar, evaluation harnesses, agentic/tool-use scaffolding, prompt and context test beds, and regression suites that let the team run, compare, and validate models quickly and reproducibly. This is a major, ongoing focus of the role.
AI Feature Development: Design, build, and ship production features powered by LLMs and other AI models, from prototype to scaled, reliable functionality within the Lexapar platform.
Retrieval & Agentic Systems: Build and optimize RAG pipelines, tool-use/agentic workflows, and orchestration layers that let models reason over legal documents and take multi-step actions reliably.
Prompt & System Design: Design and iterate on prompts, context strategies, and system architecture to maximize accuracy, consistency, and cost-efficiency across use cases.
Model Integration & Evaluation: Integrate best-fit foundation models (proprietary and open-source) into the product through the team’s harnesses, running structured evals to measure output quality, latency, and cost trade-offs before and after release.
Production Reliability: Own the AI layer end-to-end in production, monitoring, guardrails, fallback logic, and observability to ensure outputs meet legal-grade accuracy and reliability standards.
Cross-Functional Collaboration: Partner with product, engineering, and legal domain experts to translate ambiguous workflow problems into well-scoped AI features, and to validate outputs against professional legal standards.
Qualifications
AI/LLM Experience: 3+ years of hands-on experience building applications or systems on top of LLMs and other AI models, in production settings.
Harness & Eval Building: Demonstrated experience building model harnesses or evaluation infrastructure: test suites, benchmark runners, or scaffolding used to systematically compare and validate model behavior.
Applied Systems Skill: Practical experience with retrieval-augmented generation, agentic/tool-use frameworks, prompt engineering, and orchestration across multiple models or providers.
Software Engineering Fundamentals: Strong backend/software engineering skills, with the ability to design and ship robust, well-tested production systems.
Evaluation Mindset: Comfortable designing evals and quality checks to validate AI output before and after shipping, and iterating based on real usage data.
Model Fluency: Working knowledge of the LLM landscape including API-based and open-source models, fine-tuning vs. prompting trade-offs.
Autonomy & Drive: Comfortable operating with a high degree of independence, initiative, and speed in a fast-moving, resource-lean environment.
Domain Context (Preferred): Interest in or exposure to legal technology, document-heavy workflows, or other high-stakes, regulated application areas.
What we offer
The opportunity to build the AI-powered features and infrastructure at the core of a category-defining legal tech product, with direct visibility into company strategy.
A collaborative environment working alongside experienced technologists and legal professionals who speak your language.
Competitive compensation, commensurate with experience.
About Lexapar
At Lexapar, we're reimagining how legal work gets done - combining powerful Al with human expertise to make contracts faster, smarter, and more accessible. We're building technology that doesn't just automate processes, but truly transforms how businesses, lawyers, and professionals think about legal delivery.
If you're excited by the idea of shaping the next generation of legal technology — whether you're a lawyer, engineer, data scientist, or business strategist — Lexapar is the place where your ideas can have real impact. We value curiosity, clarity, and courage — and we're always looking for driven individuals who want to build something meaningful.
We're growing fast and always open to connecting with exceptional people who share our vision. If you'd like to explore opportunities to work with us.
