Sailthru JavaScript API (Personalization Engine)
The client-side Sailthru JavaScript tag (spm.v1.min.js, served from ak.sail-horizon.com) used for on-site behavior tracking, content-library sync, userSignUp/userSignUpConfirm calls and on-site personalization. It is the browser counterpart to the server-side API and is loaded as a script rather than called over REST.