[lordlarm]

Serious question: why would you not use HAProxy, nginx or similar software which arguably are more battle tested in this domain?

[jamescun]

For general rate limiting, yes HAProxy or Nginx make more sense.

Having different rate limits for different endpoints becomes unmanageable in HAProxy/Nginx; and having different rate limits say across different plans or users is all but impossible.

[Thaxll]

You can do that when the HTTP call is simple, when you need some logic in the rate limitation ( auth, login ect... ) it's impossible.

[brightball]

The best reason I can imagine is so that it can all be wrapped in your portable Go binary. Because of the portability aspect, there are a lot of use cases for Go similar to Java where there is an incentive to do everything "in Go".

[didip]

Four startups ago, I did a simpler one in Nginx using embedded Lua and Redis. It can definitely be done, but writing it in Go is easier, and funner :D