Staff Software Engineer (Trust & Safety)

Join Replit's Trust & Safety team as a Staff Software Engineer. You'll be on the front lines of defending our platform from exploitation, detecting and shutting down phishing deployments, preventing cryptomining, and stopping LLM token farming. This role offers a unique opportunity to work on AI-native security problems and have hands-on experience applying AI to security challenges. You'll own problems end-to-end, from identifying emerging abuse patterns to shipping the systems that stop them at scale.

• Concevoir et mettre en œuvre des garde-fous pour les modèles de langage (LLM) qui détectent les scénarios d'abus dans le code généré par l'IA et les interactions des agents.
• Construire des systèmes de détection alimentés par l'IA qui utilisent les LLM pour identifier les modèles malveillants, classifier les menaces et automatiser les décisions de réponse.
• Posséder l'ensemble du cycle de vie de la réponse aux abus : détection, enquête, application et gestion des appels en collaboration avec le support et le juridique.
• Ability to investigate complex abuse patterns and translate findings into automated defenses
• 8+ years of experience in security engineering, anti-abuse, trust & safety, or fraud detection
• Experience building or fine-tuning ML/LLM-based classifiers for security or abuse detection
• Familiarity with prompt injection, jailbreaking, and other LLM-specific attack vectors
• Strong programming skills in Python and/or TypeScript for building detection systems and automation
• Clear communication skills for working across Security, Support, Legal, and Engineering teams
• Experience with SQL and data analysis at scale (BigQuery, Snowflake, or similar)
• Familiarity with common attack patterns: phishing infrastructure, account takeover, credential stuffing, resource abuse
• Experience at a platform company dealing with user-generated content or compute abuse (hosting providers, cloud platforms, developer tools)
• Background in fraud detection, payment abuse, or financial crime
• Experience with CI/CD security tooling (SAST, SCA, Dependabot, Snyk)
• Familiarity with device fingerprinting, IP reputation, and email validation services
• Knowledge of container security, Linux internals, or cloud infrastructure (GCP preferred)
• Prior work with abuse reporting pipelines, trust & safety tooling, or content moderation systems