Character.AI
Software Engineer, Backend/Applied ML (Safety & Integrity)
$150K–$300K
Redwood City, CA · Hybrid · Full-time · Posted Jan 7, 2026
- Experience
- 8+ years of professional software engineering experience, with a strong emphasis on backend systems development.
- Education
- Bachelor's, Master's, or PhD degree in Computer Science, Engineering, or a related technical field.
About the job
Designs and operates scalable backend systems and applies machine learning to detect and mitigate integrity and safety risks in AI products.
What you'll do
- Build and optimize resilient backend systems for integrity and safety features.
- Develop and deploy machine learning solutions for content classification, anomaly detection, risk scoring, and generative AI safeguards.
- Set technical direction and collaborate across teams on integrity systems and AI safety.
What they ask for
- Proven experience designing, building, and operating large-scale, highly available distributed systems.
- Expertise in one or more of Python, Go, Java, or C++.
- Hands-on machine learning experience addressing integrity, trust, or safety challenges, plus understanding of the ML lifecycle.
- Strong problem-solving, communication, interpersonal, and leadership skills.
Nice to have
- Experience on a dedicated Trust & Safety, Integrity, or Risk engineering team.
- Open-source contributions or relevant publications; experience leading large cross-cutting technical projects.
Pay
$150K – $300K USD base salary
Tools
Python, Go, Java, C++
AI focus
Applies machine learning to integrity and safety, including content classification, anomaly detection, risk scoring, behavior analysis, content filtering, bias mitigation, and output monitoring for generative AI.
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