Senior Anti-Abuse Security Engineer

ActiveCampaign is the autonomous marketing platform for people at the heart of the action. They are seeking a Senior Anti-Abuse Security Engineer to architect and implement advanced detection capabilities to protect their platform from abuse and security threats.

Responsibilities:

• Architect and implement automated behavioral analysis pipelines to detect trial abuse, account takeovers, and sophisticated sending pattern anomalies
• Build continuous risk scoring systems that evaluate customer accounts across their entire lifecycle to proactively identify emerging threats
• Develop a sender reputation tracking system that seamlessly integrates with email deliverability signals to safeguard our platform's reach
• Engineer advanced analysis capabilities for campaign content, including specialized tools for URL, image, and web-based threat detection
• Deploy complex detection logic and custom Python services, utilizing Sift rules to automate real-time security responses
• Collaborate with the Security Platform Engineering team to enhance the data pipelines feeding our core security and monitoring tools
• Design automated response workflows—from account suspension and campaign throttling to manual review queuing—to mitigate abuse at scale
• Partner with Product Security Engineering to instrument AI feature telemetry and build systems capable of detecting synthetic content and inauthentic behavior

Requirements:

• 5+ years of hands-on experience building robust fraud detection, abuse prevention, or security monitoring systems
• Expert-level Python development skills, with a proven track record of writing production-grade code integrated into large-scale systems
• Deep expertise in messaging abuse patterns, specifically regarding email/SMS phishing, spam, and the nuances of sender reputation
• A strong understanding of ML-based detection systems and behavioral analytics, with the ability to build automated detection at scale with limited resources
• Technical proficiency with modern abuse tooling (e.g., Sift) and ideally experience in content moderation or text/image analysis
• Prior experience in SaaS messaging, marketing automation, or Email Service Provider (ESP) platforms a bonus—you understand the unique abuse dynamics of our industry
• A collaborative mindset and the ability to work cross-functionally with engineering, product, and security teams to drive strategic security outcomes