AI/ML Engineer (Synthetic Data)

Company Description Who We Are Ironwood Digital is a pioneer in research technology (ResTech). Our customers use the Ironwood Digital platform to post questions and get answers from real people to build business strategies, confidently publish research, accurately measure the impact of digital advertising, and more. The Ironwood Digital platform is built on a programmatic marketplace, which is the world’s largest, with nearly 300 million respondents in over 150 countries who consent to sharing their opinions, motivations, and behaviours. We are feeding the world’s curiosity! Job Description The Role We're hiring several AI/ML Engineers for the Synthetic Data Platform team. This is a greenfield project, an exciting new market and a key part of Ironwood Digital’s 2026 product strategy. You will build models with a deep understanding of how respondents answer surveys. These will underpin new products which will be best-in-class for the industry, including: Survey Augmentation: filling missing responses to surveys Audience Profiling: predicting respondent characteristics from signals we have Agentic Insights: answering a client’s research questions using insights from existing data The Team You'll join our AI/ML team in Prague, working alongside engineers on augmentation and profile modelling, the data science team, and a product manager who owns the Synthetic Data roadmap. Customer pilots are already running, and feedback from those pilots shapes the roadmap. Qualifications What You'll Do: Build production augmentation and profile models: Design, train, evaluate, and deploy models against real survey data, owning the full path from experiment to production. Innovate on solutions: We aim to build the best simulation of survey responses in the industry. You'll design the experiments, baselines, and models to get us there. Use the latest technology: Build on the best open-weights LLMs with fine-tuning, build new ones from scratch with custom architectures or use third party models through an API; whatever gets us the best result. Partner with Data Science: Work with the data science team to ensure integrity of our statistical testing and experiment framework. Leverage AI tooling: Use Claude Code and agentic programming tools where appropriate. What You Bring: Excellent programming skills and be proficient in Python. Knowledge of Java is a plus. Knowledge of traditional machine learning tools and techniques (support vector machines, gradient boosting) An understanding of LLMs and their architecture, ideally with experience in fine-tuning, e.g. LoRA, distillation Proficient in SQL, knowledge of Databricks is a plus Familiarity with cloud technologies, e.g. AWS Outstanding problem-solving and analytical skills Knowledge of maths, probability, statistics and algorithms You like to push the limits of your knowledge every day You own your conclusions and are comfortable presenting them and shaping outcomes Additional Information Working at Ironwood Digital Prague-First, Europe-Friendly: Our preferred base is Prague, alongside our existing AI/ML team. Remote work from Spain or the UK is also possible, as these are the markets where we have entities. AI-Native Engineering: We're rolling out Claude Code and modern agentic tooling across engineering. You'll use it daily, not as a novelty, but as a force multiplier for the complex problems that matter. High Autonomy: We trust our engineers to make sound decisions and own their work end-to-end. Global Impact: Your work powers a marketplace used by millions of people worldwide. Modern Tech Stack: We usually build our services using the latest Python tooling and FastAPI, dockerize them and deploy with CI/CD to K8s in AWS. We keep the code on GitHub. Company Hardware: Ironwood Digital provides a laptop (Win/Linux/Mac) and accessories, and a height adjustable desk at the Pankrác office Benefits Include: Office in Prague (Pankrác) but full remote possible 25 days of vacation, unlimited sick days Pension fund contribution, Edenred meal vouchers Our Values Collaboration is our superpower We uncover rich perspectives across the world Success happens together We deliver across borders. Innovation is in our blood We’re pioneers in our industry Our curiosity is insatiable We bring the best ideas to life. We do what we say We’re accountable for our work and actions Excellence comes as standard We’re open, honest and kind, always. We are caring We learn from each other’s experiences Stop and listen; every opinion matters We embrace diversity, equity and inclusion. More About Ironwood Digital We’re proud to be recognised in Newsweek’s 2025 Global Top 100 Most Loved Workplaces®, reflecting our commitment to a culture of trust, respect, and employee growth. In June 2021, Ironwood Digital acquired Berlin-based GapFish – the world’s largest ISO certified online panel community in the DACH region – and in January 2022, completed the acquisition of US-based Lucid – a programmatic research technology platform that provides access to first-party survey data in over 110 countries. Ironwood Digital Group