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kotlinlang

Also: we noticed that things like `Cookie.expires` has become a `GMTDate` -- what was the thinking behind moving away from standard Java date types to a homebrewed date API?

Ktor is multiplatform, it can't rely on Java types.

What other platforms does Ktor target? Isn't it pretty coupled to a lot of JVM stuff?

Afaik it also runs on native (at least experimentally) and JS at some point

Most of the library is written multi-platform. It does provide helpers for migrating between JVM/ktor types (ie, `Url` vs `URI`) and entry points for using JVM engines (ie, Netty, Jetty), but for the most part, it's fairly uncoupled