Senior AI Engineer
LexroomAI-powered legal company
Barcelona, Spain€70,000 - €100,000Senior
Left Lane Capital
Eurazeo
Base10 Partners
Acurio Ventures
Entourage
View Different
Data & AINew
About the role
TL;DR
Design and build AI systems for legal tasks, fine-tune LLMs, and optimize search pipelines.
- •Lexroom is building the AI platform where legal work gets done.
- •In just over two years, we've grown from zero to €25M ARR, and today more than 20,000 legal professionals across Italy, Spain, Germany, France, and Bulgaria rely on Lexroom.
- •We're backed by $73M from Left Lane Capital, Base10 Partners, and Eurazeo, and we're a team of around 300 builders who move fast, say things straight, and own each outcome.
- •Our next goal? Become Europe's most-used legal product.
- •Why Lexroom? Shape the Standard: Be part of the team setting the benchmark for legal AI in Europe.
- •Work with the Best: Collaborate with exceptional colleagues in a culture that values competence, curiosity, and ambition.
- •Deliver Meaningful Results: Your contribution will directly influence how legal professionals work—faster, clearer, and more efficiently.
- •At Lexroom, we leave buzzwords behind.
- •Here, you’ll build something that lasts: a trusted platform, a strong reputation, a new standard for the legal world.
- •What You'll Do Design and build agent-driven and RAG-based AI systems to solve complex legal tasks with precision and efficiency.
- •Fine-tune and post-train LLMs using cutting-edge supervised and reinforcement learning techniques to raise response quality.
- •Develop and optimize large-scale search pipelines for LLM-powered agents.
- •Implement and refine NLP algorithms to extract, structure, and validate information from legal documents.
- •Run end-to-end evaluations to pinpoint bottlenecks, measure performance, and guide continuous improvements.
- •Work closely with legal experts to design evaluation protocols and build reliable, domain-specific datasets that strengthen every layer of the stack.
- •Maintain technical excellence by following established best practices, coding standards, and rigorous code-review processes.
- •What You’ll Bring Proven expertise in building and managing robust ML pipelines.
- •Strong Python skills with hands-on experience in LLM research and deep learning systems.
- •Knowledge of search technologies such as full-text search, vector databases, or other large-scale retrieval systems.
- •Collaborative mindset and readiness to work with legal experts, researchers, and engineers to keep improving the product.
- •Familiarity with MLOps and integrating ML models into production backends (a strong plus).
- •Up-to-date with LLM innovation, ideally with experience in pre-training or deploying large-scale models in real-world scenarios.
- •Fluency in English, both written and spoken, knowledge of Italian is a plus.
- •What Sets Us Apart An Exceptional Team.
- •At Lexroom.ai, you’ll work alongside top talent in tech and legal AI.
- •Our focused teams operate with purpose and autonomy, so every contribution delivers visible results.
- •You’ll collaborate with people who pair innovation with rigor, curiosity with discipline, ambition with depth.
- •Growth that Matters.
- •We hire exceptional people to make a difference—and we give them space to lead.
- •As we scale, your work will shape the future of legal technology and set new standards for the field.
- •Impact is defined by vision and execution, not by age or title.
- •If you’re ready to take responsibility, you’ll find real opportunities to grow and lead high-stakes projects.
- •Rewarding Your Contribution.
- •We value excellence and share success: Annual Salary Range: €70,000
- •€100,000 Equity Package: Align your growth with the company’s long-term success.
- •Benefits That Matter Hybrid Work: Flexibility to balance remote work with in-person collaboration at our Barcelona office.
- •Health Coverage: Comprehensive insurance to keep you secure and focused.
- •Meal Vouchers: Daily support for your lunch breaks.
- •Performance Bonuses: Rewards directly tied to measurable results.
- •Team Retreats & Off-sites: Dedicated time to connect, collaborate, and spark bold ideas. **At Lexroom.ai, ambition meets discipline and purpose.
- •We’re not just building a product—we’re setting a new standard for the legal world.
- •If you’re ready to contribute to something lasting and meaningful, we’d love to hear from you.**
Required skills
PythonLLMsNLP
Domain expertise
legaltechaiproductivity
Benefits & perks
Equity Package, Health Coverage, Meal Vouchers, Performance Bonuses, Team Retreats & Off-sites, Hybrid Work
Tech stack
PythonLLMsNLPDockerKubernetesGitLinux