Arcjet has launched Advanced Bot Signals, a CAPTCHA-free bot detection system that collects client-side browser telemetry via a WebAssembly module and evaluates it server-side. Unlike edge-only bot scoring, it integrates directly into application logic so developers can enforce protection only on sensitive routes like login, signup, or checkout — where application context (user state, business rules, downstream costs) matters most. The system stores a token in a cookie; missing cookies are an easy automation indicator, while present ones trigger deeper signals analysis. A real-world example shows it stopping newsletter spam without interrupting legitimate users. The approach avoids CAPTCHA UX friction and is compatible with Next.js, Python, Deno, Bun, NestJS, FastAPI, Flask, and other frameworks.
