Deno deploy is an Edge hosting service which deploys your Deno apps instantly. Because it already likes on the edge, you can add your middleware in your app. As an example, Deno Fresh supports this intrinsically, with no need to create a separate functions folder for your host or anything of that nature. You can use the middleware to update security headers or page HTML body. On top you might want to check for an authorisation cookie and redirect the visitor to the log page, it they are not yet logged in.