Senior LLM Engineer

Technical · San Sebastian, Spain

Multiverse Computing is a rapidly growing deep-tech company founded in 2019. We are one of the largest quantum software companies in the EU, recognized by CB Insights (2023 and 2025) as one of the 100 most promising AI companies in the world. With 180+ employees worldwide, our multicultural and international team develops advanced quantum and AI solutions to tackle complex challenges across finance, energy, manufacturing, telecoms, and beyond.

Our mission is to empower organizations to achieve significant competitive advantage through cutting-edge quantum computing and AI technologies.

About the Role

We are seeking a Senior LLM Engineer to lead the development and optimization of large language models and advanced AI systems. This role focuses on architecting and implementing state-of-the-art LLM solutions that drive our products and support our customers' AI transformations.

Responsibilities

• Design and implement large language models and transformer-based architectures

• Optimize LLM training and inference for performance and efficiency

• Develop tools and frameworks for model evaluation and benchmarking

• Lead research initiatives in advanced NLP and AI techniques

• Collaborate with product teams to translate LLM capabilities into customer solutions

• Mentor junior engineers on ML best practices and LLM development

• Stay current with latest advances in large language models and AI research

• Contribute to internal knowledge sharing and technical documentation

What we are looking for:

• 6+ years of experience in machine learning or AI engineering

• 3+ years hands-on experience developing or fine-tuning large language models

• Deep understanding of transformer architectures and modern NLP techniques

• Strong proficiency in Python and deep learning frameworks (PyTorch, TensorFlow)

• Experience with distributed training and inference optimization

• Familiarity with LLM frameworks and tools (HuggingFace, LangChain, etc.)

• Knowledge of model compression techniques (quantization, distillation, pruning)

• Strong understanding of Large Language Model capabilities and limitations

• Published research or contributions to open-source ML projects is a plus

• Excellent communication and leadership skills

• Bachelor's degree in Computer Science, Mathematics, or equivalent professional experience

What we offer:

• Competitive salary (€65,000 - €85,000 annually based on experience)

• Stock options in a well-funded deep-tech company

• Flexible work arrangements (hybrid model)

• Professional development budget and training opportunities

• Health insurance and retirement benefits

• International, collaborative team environment

• Direct impact on advancing AI and quantum computing innovation

If you're passionate about large language models and want to shape the future of AI, we'd love to hear from you.