我正在考虑将Java(Android)库移植到Kotlin.我真的很喜欢Kotlin，相对于Java的好处应该会减少库中的bug数量.
Since the library is targeting a resource constrained environment I'm worried that by porting the library to Kotlin there will be extra overhead.
Does a Kotlin library (distributed as .class files) introduce any runtime or extra overhead versus a Java library?
Will the resulting Android app be any larger or slower because of Kotlin?
Kotlin has many optimizations specifically that help Android. If you read through blog posts you can see how it has constantly reduced stdlib size, and amount of classes at every release.
Will the resulting Android app be any larger or slower because of Kotlin?
No
Does a Kotlin library (distributed as .class files) introduce any runtime or extra overhead versus a Java library?
标准库非常小，它的许多函数都是内联的，这意味着它们在编译后不存在，只是成为内联代码.Proguard也能处理很多事情.
Since the library is targeting a resource constrained environment I'm worried that by porting the library to Kotlin there will be extra overhead.
您没有定义哪些资源受到限制.Kotlin不会使用更多内存，也不会使用更多磁盘，而且stdlib很小.
我真的很喜欢Kotlin，与Java相比的好处应该可以减少库中的bug数量.
Kotlin is popular on Android for a reason, and you should take that as a sign that there are many more benefits than negatives. Really you can see this for yourself by having a small example in Java and small in Kotlin and compare the difference. Proguard both, have the same type of build pipeline.