I use Chef's test kitchen for testing my chef recipes, and I do so at Digital Ocean because they have a plugin (https://github.com/test-kitchen/kitchen-digitalocean). It looks like someone has independently started work on a linode plugin for vagrant, which is the underlying technology used by test kitchen to manage boxes. I've also been looking at Rexify as an alternative to chef, and it includes a component Rex::Box for managing virtual machine instances (WebService::Linode could probably be wrapped in a Rex::Box provider).