Character

ABOUT THE ROLE AND TEAM We are building the future of open-ended interactions between people and intelligent agents. This requires rethinking design, user interfaces, workflows and interactivity from first principles. We’re looking for a Core Product engineer who is genuinely excited about this future and can make significant contributions to our front-end development efforts. If you are a skilled software engineer with a deep passion for front end development, design, craft, and you thrive in a fast-paced, agile environment, we encourage you to apply for this exciting opportunity. WHAT YOU’LL DO - Develop highly performant, visually appealing, and user-friendly interfaces that push the boundaries of what's possible. - Enhance and refine our user interface, focusing on engaging our users by fulfilling their needs, desires, and expectations. - Collaborate closely with the design team to translate visionary concepts into tangible user experiences and product interfaces. - Establish, evolve, and maintain design foundations, systems, and patterns for the team, setting the bar for product consistency and quality. - Collaborate with others to define and implement new product features and design patterns WHO YOU ARE - Experience as a Front-End or Full-Stack Software Engineer with a strong focus on user experience and design systems - Deep understanding of Typescript, React, React Native, Tailwind, HTML, and modern front-end best practices. - Demonstrated experience with building features and experiences for consumer products - Passionate about the pixels, an exceptional eye for detail, and a focus on craft and polish - Proven ability to work in a fast-paced development environment and deliver timely results. - Excellent communication and collaboration skills across engineering, product, design, and data. ABOUT CHARACTER.AI Character.AI http://Character.AI empowers people to connect, learn and tell stories through interactive entertainment. Over 20 million people visit Character.AI http://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.

Character.AI is looking for a high-leverage, force-multiplying Technical Program Manager (TPM) to partner directly with our Chief Product Officer (CPO). In this role, you will operate across the entire product and design purview of the CPO to ensure our core development engines run seamlessly. This is not a traditional, rigid corporate TPM role. We are looking for someone with "fixer energy"—a relentless, high-agency problem-solver who possesses a founder's mindset, exceptional execution skills, and the technical weight to act as a core operational extension of the CPO. You will be the ultimate guardian of momentum: chasing down engineering bottlenecks, optimizing cross-functional roadmaps, and ensuring team velocity scales alongside our technology. Key Responsibilities Operational Rigor & Technical Execution - Keep the Trains Running on Time: Own the end-to-end execution of major initiatives under the CPO's umbrella, ensuring critical product, design, and engineering milestones are hit without friction. - Eliminate Blockers: Proactively manage cross-functional dependencies across product, design, and engineering teams. Your primary metric of success is that development is never left stalling for information or decisions. - Drive Accountability: Attend weekly core team meetings, capture critical technical notes, synthesize action items, and relentlessly chase down owners to ensure rigorous follow-through. - Process Evolution: Analyze how teams are currently working and design/implement lightweight, scalable processes to improve cross-functional execution across the software development life cycle (SDLC). Strategic Alignment & Technical Delivery - Product & Design Sync: Build deep context on the CPO's vision and product strategy to seamlessly bridge the gap between creative design concepts and technical implementation. - Unstructured Problem Solving: Roll up your sleeves to solve ambiguous, complex technical or operational problems that don't neatly fall into a single team's bucket. - AI-Driven Workflows: Actively leverage AI tools (like Gemini) to optimize team workflows, ensure project knowledge is captured efficiently, and explore agentic workflows to enhance team intelligence. Who You Are - Founder Energy & High Agency: You possess extreme ownership. You don't wait to be told what to do—you see a gap, you fill it, and you autonomously solve problems. - Execution Machine: You have a strong background in technical program management, product management, or an intensive technical operations role where you have successfully navigated fast-moving tech roadmaps. - High Cognitive Agility: You can pivot from a deep-dive technical alignment with engineers to high-level roadmap prioritization with design and product leaders in the span of an hour. - Relentless Communicator: You are crisp, direct, and excellent at synthesis. You know how to get to the point quickly and ensure information flows seamlessly across the organization. - AI-Curious: You have a genuine fascination with artificial intelligence and are eager to experiment with cutting-edge tools to optimize operational efficiency. Qualifications & Background We care far more about your capability, trajectory, and "fixer energy" than a rigid checklist of past titles. You might be an incredible fit if you are a: - Technical Program Manager (TPM) or Product Manager (PM) looking for a highly impactful, executive-facing execution role. Experience enabling product/design teams to become "AI-ready" is a major plus. - Former Founder who loves the early-to-mid stage tech grind but wants to focus heavily on hyper-scale execution and organizational stability. - Management Consulting Alum (particularly from technical or digital practices) with a proven track record of intensive work, extreme attention to detail, and cross-functional influence. - Seasoned Operational Leader—a highly capable, mature operator who brings stability, structured execution, and mentorship to a fast-growing team. A

ABOUT THE ROLE AND TEAM Joining us as a Research Engineer on the Multimodal team, you'll be at the forefront of building and advancing video and image generation models that bring AI characters to life in entirely new ways. Your work will directly shape how millions of users experience rich, expressive, and visually compelling AI interactions every day. The Multimodal team is responsible for training, fine-tuning, and deploying cutting-edge image, audio and video generation models that power Character.AI http://Character.AI's visual experiences. We work across the full model lifecycle — from data pipelines and training to deployment and product integration. As a Multimodal Research Engineer, you will own and advance our video model training efforts, including joint audio-visual generation and image-to-video. You will collaborate across research, product, and infrastructure to push the boundaries of what AI-generated visuals can look and feel like at scale. WHAT YOU'LL DO - Lead fine-tuning and continued training of video generation models, including image-to-video and joint audio-visual generation. - Design and experiment with novel model architectures for multimodal generation, including multimodal conditioning (voice, structured text, reference images). - Leverage techniques such as LoRA, RLHF, and full-parameter fine-tuning to improve model quality across diverse visual scenarios. - Design and build large-scale data pipelines and automated annotation workflows to support continuous model improvement. - Explore model compression, inference acceleration, and serving optimizations to enable efficient real-time video processing at scale. WHO YOU ARE - Strong passion for pushing the boundaries of visual AI, with a self-driven, hands-on approach to solving complex technical problems - Proficient in PyTorch with end-to-end experience across data processing, model training, and deployment - Solid understanding of video and image generation architectures, including diffusion models, DiT, ControlNet, and SOTA video generation models - Experience with multimodal model training, including working with audio, vision, and language modalities together - Experience with distributed training tools (FSDP, DeepSpeed, etc.) - Experience with large-scale data processing, dataset construction, and automated data cleaning NICE TO HAVE - Experience with joint audio-visual or speech-conditioned generation models - Experience with AIGC, video effects, character animation, or asset generation products - Familiarity with ML deployment and orchestration (Kubernetes, Slurm, Docker, cloud platforms) - Publications in relevant venues (NeurIPS, ICLR, CVPR, ECCV, ICCV, or similar) ABOUT CHARACTER.AI Character.AI http://Character.AI empowers people to connect, learn and tell stories through interactive entertainment. Over 20 million people visit Character.AI http://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.

ABOUT THE ROLE AND TEAM Joining us as a Research Engineer on the Post-Training team, you'll be diving into the exciting world of fine-tuning AI models, optimizing their performance, and ensuring they meet the highest standards of quality and efficiency. Your work will directly contribute to our groundbreaking advancements in AI, helping shape an era where technology is not just a tool, but a companion in our daily lives. At Character.AI http://Character.AI, your talent, creativity, and expertise will not just be valued—they will be the catalyst for change in an AI-driven future. The Post-Training team is responsible for developing our powerful pretrained language models into intelligent, engaging, and aligned products. As a Post-Training Researcher, you will work across teams and our technical stack to improve our model performance and training methods, including data, compute and algorithms. You will get to shape the conversational experience of millions of users per day. WHAT YOU'LL DO - Develop alignment algorithms and loss functions to improve data sample efficiency. - Write data pipelines to process diverse web data into a format models can ingest. - Identify quality signals to understand our model’s performance in the real world. - Design sampling algorithms to improve serving efficiency of large generative models. WHO YOU ARE - "All Industry Levels": have at least PhD (or equivalent) - 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 (reinforcement learning, transformers, etc) - Track-record of exceptional research or creative applied ML projects 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) - Publications in relevant academic journals or conferences in the field of machine learning ABOUT CHARACTER.AI Character.AI http://Character.AI empowers people to connect, learn and tell stories through interactive entertainment. Over 20 million people visit Character.AI http://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.

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 http://Character.AI empowers people to connect, learn and tell stories through interactive entertainment. Over 20 million people visit Character.AI http://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.

ABOUT THE ROLE We’re looking for seasoned ML Infrastructure engineers with experience designing, building and maintaining training and serving infrastructure for ML research. Responsibilities: - Provide infrastructure support to our ML research and product - Build tooling to diagnose cluster issues and hardware failures - Monitor deployments, manage experiments, and generally support our research - Maximize GPU allocation and utilization for both serving and training Requirements: - 4+ years of experience supporting the infrastructure within an ML environment - Experience in developing tools used to diagnose ML infrastructure problems and failures - Experience with cloud platforms (e.g., Compute Engine, Kubernetes, Cloud Storage) - Experience working with GPUs Nice to have - Experience with large GPU clusters and high-performance computing/networking - Experience with supporting large language model training - Experience with ML frameworks like Pytorch/TensorFlow/JAX - Experience with GPU kernel development ABOUT CHARACTER.AI Character.AI http://Character.AI empowers people to connect, learn and tell stories through interactive entertainment. Over 20 million people visit Character.AI http://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.