Character.AI · 4 days ago
Research Engineer, AI Safety & Alignment
Redwood City, CA
Full-time
Onsite
Senior LevelCharacter.AI empowers people to connect, learn and tell stories through interactive entertainment. As a Research Engineer, you will tackle critical challenges in AI safety and alignment, conducting foundational research and developing techniques to ensure models behave according to human values. Your work will bridge theoretical research and practical application, contributing to both user safety and the broader scientific community.
AppsArtificial Intelligence (AI)Generative AIInformation TechnologyMobile AppsSoftware
Responsibilities
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
Qualification
Required
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
Preferred
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
Company
Character.AI
Character.ai provides open-ended conversational applications in which users create characters and converse with them.
Founded in 2021
51-200 employees
H1B Sponsorship
Character.AI has a track record of offering H1B sponsorships. Please note that this does not
guarantee sponsorship for this specific role. Below presents additional info for your
reference. (Data Powered by US Department of Labor)
Distribution of Different Job Fields Receiving Sponsorship
Represents job field similar to this job
Trends of Total Sponsorships
2025 (9)
2024 (16)
2023 (6)
2022 (1)
Funding
Current Stage
Growth StageTotal Funding
$150.08MKey Investors
Andreessen Horowitz
2023-03-23Series A· $150M
2023-01-24Seed· $0.08M
Leadership Team
Karandeep Anand
CEO
Recent News
2025-12-19
2025-12-13
2025-12-12
Company data provided by crunchbase