Research Engineer, Post-Training (All Industry Levels)
Hybrid (Redwood City or New York City)$225k - $400kFull-timePosted 11mo ago
About the role
Research Engineer on the Post-Training team focusing on fine-tuning AI models, improving performance, and aligning products. Collaborates across teams to enhance model data, compute, and algorithms, shaping conversational experiences for millions of users.
Responsibilities
- 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.
Qualifications
- PhD or equivalent (All Industry Levels)
- 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
Skills
Required:PhD or equivalentProduction-facing and training codeGPUs (training, serving, debugging)Data pipelines and data infrastructureModern ML techniques (reinforcement learning, transformers)
Benefits
- Top-notch health coverage for you & your family, with majority of the premium covered
- Generous 401(K) contribution
- Paid leave up to 20 weeks for new parents
- 4 weeks of PTO
- Daily in-office catering plus a monthly Doordash stipend
- Monthly wellness stipend
Last updated Jul 15, 2026. Interested? Apply on the company site.
About Character.AI
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