Software Engineer, Backend/Applied ML (Safety & Integrity)

About this role

Character.AI is seeking an experienced Backend/Applied ML engineer to join their Safety Engineering team in designing and scaling systems that address integrity and safety challenges in AI interactions. You'll architect robust backend solutions, develop ML models for content classification and risk detection, and provide technical leadership on platform trustworthiness initiatives.

What you'll do

• Design and maintain scalable backend systems for integrity and safety features
• Lead technical design of solutions to detect and mitigate AI-related risks and content integrity issues
• Develop and deploy machine learning models for content classification, anomaly detection, and risk scoring
• Collaborate cross-functionally with product, data science, security, and operations teams
• Drive long-term technical vision and roadmap for backend integrity systems
• Mentor engineers and champion engineering best practices across the organization

What they're looking for

• Backend system design and distributed systems architecture
• Python, Go, Java, or C++ programming
• Machine learning lifecycle (data preparation, feature engineering, model training, deployment)
• Content classification and anomaly detection
• Generative AI safety and bias mitigation techniques
• Problem-solving in ambiguous, complex technical environments
• Technical leadership and cross-functional communication
• System optimization and performance analysis