Character.AI
Software Engineer, Applied ML (Discovery, Recommendation & Search)
$200K–$300K
Redwood City, CA · Hybrid · Full-time · Posted Dec 18, 2025
- Experience
- 5+ years of industry experience.
- Education
- B.A.S. in Computer Science or equivalent experience.
About the job
Build and optimize applied ML models and backend infrastructure for Character.AI discovery features, including recommendations, ranking, and search.
What you'll do
- Design and implement ML models and infrastructure, including data pipelines, model training, and model serving.
- Develop ML backend systems for discovery surfaces and support new AI-generated content formats.
- Optimize existing ML systems in collaboration with product, data science, and data platform teams.
What they ask for
- B.A.S. in Computer Science or equivalent experience.
- 5+ years of industry experience.
- Experience building or consuming RESTful and gRPC-based web services, and managing cloud infrastructure (GCP, AWS, or Azure).
- Familiarity with a popular ML framework such as Pytorch or Tensorflow; experience with performant services in a modern typed language and CI/CD pipelines with automated testing.
Nice to have
- Experience shipping intelligent features end-to-end and building pipelines from data ingestion to model training.
- Experience with production AI/ML systems, GPU/TPU deployment optimization, or vector databases and feature storage.
Pay
$200K – $300K (base salary)
Tools
RESTful, gRPC, GCP, AWS, Azure, Pytorch, Tensorflow, GPU/TPU
AI focus
Applied ML for recommendations, ranking, search, and AI-generated content, including model optimization, training, and serving.
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