Research Engineer, AI Safety & Alignment
At a glance
Mid-level AI Research role at Character.AI. Redwood City · full-time · $225,000–$400,000 base.
aimlroles summary, based on the employer's posting.
What you'll do
- Build ways to measure how well large language models meet safety and alignment goals
- Develop methods for alignment, value learning and interpretability in models
- Probe models for weaknesses, then address bias, toxicity and other harmful outputs
- Turn safety research into usable approaches with engineering and product teams
- Track new AI safety research and share findings through papers or presentations
What you bring
- A PhD or equivalent background in computer science, machine learning or a related area
- You can write clear code for training and production use, and work with GPUs across training, serving or debugging
- You have experience with data pipelines and infrastructure, plus a strong grasp of transformers and reinforcement learning
Who this fits
This mid-level research engineering role suits someone focused on applying machine learning to AI safety and alignment. The role is based in Redwood City with a hybrid arrangement.
From the employer
About the role and team
Joining us as a Research Engineer, you'll be at the forefront of tackling one of the most critical challenges in AI today: safety and alignment. Your work will be pivotal in understanding and mitigating the risks of advanced AI, conducting foundational research to make our models safer, and solving the core technical problems of AI alignment—ensuring our models behave in accordance with human values and intentions.
The Safety team is dedicated to pioneering and implementing techniques that make our models more robust, honest, and harmless. As a Research Engineer, you will bridge the gap between theoretical research and practical application, writing high-quality code to test hypotheses and integrating successful safety solutions directly into our products. Your research will not only protect millions of users but also contribute to the broader scientific community's understanding of how to build safe, beneficial AI.
What you'll do
Develop and implement novel evaluation methodologies and metrics to assess the safety and alignment of large language models.
Research and develop cutting-edge techniques for model alignment, value learning, and interpretability.
Conduct adversarial testing to proactively uncover potential vulnerabilities and failure modes in our models.
Analyze and mitigate biases, toxicity, and other harmful behaviors in large language models through techniques like reinforcement learning from human feedback (RLHF) and fine-tuning.
Collaborate with engineering and product teams to translate safety research into practical, scalable solutions and best practices.
Stay abreast of the latest advancements in AI safety research and contribute to the academic community through publications and presentations.
Who you are
Hold a PhD (or equivalent experience) in a relevant field such as Computer Science, Machine Learning, or a related discipline.
Write clear and clean production-facing and training code
Experience working with GPUs (training, serving, debugging)
Experience with data pipelines and data infrastructure
Strong understanding of modern machine learning techniques, particularly transformers and reinforcement learning, with a focus on their safety implications.
Are passionate about the responsible development of AI and dedicated to solving complex safety challenges.
Nice to Have
Experience with product experimentation and A/B testing
Experience training large models in a distributed setting
Familiarity with ML deployment and orchestration (Kubernetes, Docker, cloud)
Experience with explainable AI (XAI) and interpretability techniques.
Have research in AI safety, alignment, ethics, or a related area.
Knowledge of the broader societal and ethical implications of AI, including policy and governance.
Publications in relevant academic journals or conferences in the field of machine learning
About Character.AI
Character.AI empowers people to connect, learn and tell stories through interactive entertainment. Over 20 million people visit Character.AI every month, using our technology to supercharge their creativity and imagination. Our platform lets users engage with tens of millions of characters, enjoy unlimited conversations, and embark on infinite adventures.
In just two years, we achieved unicorn status and were honored as Google Play's AI App of the Year—a testament to our innovative technology and visionary approach.
Join us and be a part of establishing this new entertainment paradigm while shaping the future of Consumer AI!
At Character, we value diversity and welcome applicants from all backgrounds. As an equal opportunity employer, we firmly uphold a non-discrimination policy based on race, religion, national origin, gender, sexual orientation, age, veteran status, or disability. Your unique perspectives are vital to our success.