Mid/Senior AI LLM Engineer (Full Remote - Europe)

Role overview

Improve open weight language models that power a large consumer AI product, taking work from failure analysis and experiments through production deployment. The role spans data, post training, evaluation, and model behavior, with a focus on personalization, consistency, multilingual interaction, and faster experimentation.

Responsibilities

- Fine tune open weight models using supervised fine tuning, LoRA or QLoRA, and methods such as DPO or GRPO. - Investigate model failures and choose whether to address them with data, post training, prompts, or classifiers. - Build training datasets and evaluations that guide subsequent model development. - Improve model behavior across personalization, tone, consistency, languages, and group conversations. - Deploy model improvements and use real user behavior to inform further iterations. - Make training experiments faster, easier to compare, and more reproducible.

Requirements

- Hands on experience post training open weight LLMs for a user facing product and shipping them to production. - Experience in a product or business where AI is central, with fine tuning as a core part of your work. - Strong Python, PyTorch, and Hugging Face skills, including GPU training and debugging. - Ability to build datasets and evaluations, make evidence based decisions, and take work from notebooks into production. - Daily use of AI tools in engineering work. - Comfort working with uncensored models and explicit adult content, including harmful material when developing or evaluating moderation systems.

Nice to have

- Experience with conversational or roleplay AI, personalized consumer products, or multilingual models. - Background in moderation, safety, adversarial testing, multimodal systems, or open source model training.

Benefits and work setup

- Fully remote, with work from anywhere and a preference for long term B2B arrangements, though contract terms are flexible. - Four weeks of paid time off and an annual team gathering. - Monthly health insurance support and access to individual wellbeing sessions, including for up to three family members. - Coworking visits, professional learning funds, and budgets for computer equipment; a laptop and premium AI tools are provided.