Well, if it's worth adding a whole new layer to my stack to deal with this kind of stuff, surely it's even more worth extending an existing layer to deal with it; as a corollary, if I know enough about the problems I'm having to know what I need Templar to do for me, then I know enough about them to know what I need nginx to do for me, too.

Again, though, maybe I'm just missing the point here. Perhaps it would help to know what use case prompted Templar's development.

In my opinion, the draw is the ability to use it when connecting to third party endpoints (so you can't control how they cache or how they respond) with third party libraries (which means you lack fine grained control over timeouts and caching on your end).

Personally, I'd rather gain the necessary control through the request mechanisms, but for a quick-and-dirty solution, this would probably work pretty well.

It's very true that things like timeouts are done better within the client library. But Templar can combine timeouts with caching, allowing an API to appear to still be active and returning something even when it's just very slow.

Because a cache is best when it's populated often, it make sense to put that into a service that many different processes on different machines can use.

Everything within templar can be done by adding capabilities to client libraries, no argument. But most client libraries don't provide these capabilities in one programming language, let alone many of them. By having the functional available as a service, Templar provides these capabilities fairly transparently (and even more transparently in the future when there is per/host and per/url configuration).

That assumes nginx has the capability to do what Templar does and I don't believe that's true.