My upvote for Unpoly. Used it in severa projects and it's awesome. Only drawback I've found so far is that the source is CoffeScript, so it might be a bit harde

My upvote for Unpoly. Used it in severa projects and it's awesome. Only drawback I've found so far is that the source is CoffeScript, so it might be a bit harder to read the internals when necessary. But In my opinion it gets a lot of things right, specially around form submissions, validation, error handling, modals, history, navigation, passive updates, etc. It is like Turbolinks++.