They're kind of differently inflexible. :-) So, they're both moving away from the generality of the bindings, which are a pretty faithful mapping of the capab

They're kind of differently inflexible. :-) So, they're both moving away from the generality of the bindings, which are a pretty faithful mapping of the capabilities of the API, to make simplifying assumptions to make the API easier to use. But they're so different that it's difficult to compare directly. The Shopify app is a pretty normal web app. None of its users know that there's anything API-ish about it, nor do they care. You can set weights, but only for pre-specified things: https://skitch.com/scotchi/rw5a3/directed-edge-expressrex-for-shopify https://skitch.com/scotchi/rw5a3/directed-edge-expressrex-fo... There are a bunch of features of the API that aren't exposed via the Rails plugin (even a couple that are used in the Shopify app) and it does, at present, assume that you're just latching onto a preexisting model. That said, using the Rails plugin is kind of like using a C API from C++ -- you can drop down to the lower level of abstraction if you need to. So while the plugin is, say, a minimum viable plugin at the moment, you can still get the full flexibility of the bindings at will if you're willing to trade some simplicity.