Research Engineer - Customer Feedback AI Scaleup

Want to work on NLP problems where model quality genuinely matters? Interested in building and evaluating production transformer models rather than simply orchestrating APIs? Looking for a role where you'll directly shape the next generation of AI-powered customer intelligence products? We're partnered with a fast-growing AI product company helping global brands better understand their customers through machine learning and natural language processing. Their platform analyses vast volumes of unstructured customer feedback to uncover actionable insights, enabling organisations to make better product and customer experience decisions. Rather than relying solely on third-party models, the team develops and deploys proprietary NLP and language models across core product workflows. This is an opportunity to join a highly technical, low-ego environment where applied research, experimentation and real-world impact sit at the centre of the roadmap. Role Summary Seeking a Senior Machine Learning Scientist to build, fine-tune and evaluate production NLP and language models across customer feedback intelligence products. You'll work on problems spanning sentiment analysis, retrieval, search, clustering, taxonomy generation and GenAI-powered insight generation while owning model performance from experimentation through deployment. Key Responsibilities * Train, fine-tune and optimise transformer models, LLMs and SLMs for production use cases * Design and execute rigorous evaluation frameworks, experiments and benchmarking processes * Build and improve semantic search, retrieval and reranking systems * Develop solutions across aspect-based sentiment analysis, classification and taxonomy generation * Partner closely with Product and Engineering teams to ship production-ready ML systems * Contribute to model serving, monitoring and continuous improvement processes * Mentor colleagues and bring relevant advances in NLP, GenAI and Machine Learning into production Key Details Salary: £90,000 (stretch to £100k) + equity Working Model: 100% remote flexibility, with optional access to the London (Spitalfields) office Tech Stack: Python, PyTorch, Hugging Face, Transformers, LoRA, PEFT, LLMs, SLMs, Qwen, Gemini, Retrieval Systems, Embeddings, Semantic Search Visa Sponsorship: Available Interested? Please apply below.