Senior Software Engineer, Risk

Defend Replit's platform from AI-native threats by building detection systems.

• •The Risk team defends Replit's platform from exploitation by building detection systems, heuristics, and automated responses, with a focus on AI-native threats like prompt injection and malicious AI-generated code.
• •Key Responsibilities Design and implement LLM guardrails and AI-powered detection systems.
• •Build and operate abuse detection for phishing, cryptomining, account takeover, and fraud.
• •Design automated response mechanisms and own the abuse response lifecycle.
• •Analyze attack patterns using BigQuery and maintain internal monitoring tools.
• •Integrate security scanners into CI with performance SLAs.
• •Requirements 4+ years in security engineering, anti-abuse, trust & safety, or fraud detection.
• •Strong programming in Python and/or TypeScript.
• •Experience with SQL and data analysis at scale (BigQuery, Snowflake).
• •Experience building or fine-tuning ML/LLM-based classifiers and familiarity with prompt injection vectors.