In addition to saving time on software development, Vercel Edge can also:

Personalize content: based on the request, Edge connects to configuration tools to run A/B tests for site visitors. If a visitor is part of an A/B test, they’ll be routed to a variant from the edge server. Developers no longer need to load heavy client-side personalization libraries or worry about layout shifts from validating whether users were part of the test.
Localization: Edge Middleware API contains a geolocation object pre-populated with information about the visitor’s geographic location based on their IP address. The site can then conditionally show or restrict content based on a brand’s regulatory requirements. Built-in geolocation capabilities save money – companies no longer have to pay for an additional geolocation service and customers get a seamless experience.
Authentication: when a visitor requests an application, Edge Middleware validates the request to check the visitor’s authorization. If the user isn’t authorized, Edge Middleware routes them to a page explaining they don’t have access (even if that page is cached on the CDN). With customers, faster, easier log-in authentication means they can be routed to offers tailored just for them, based on previous purchases with no gaps or pauses in the experience.