Coding standards
As an open-source project, there will be a lot of eyes on our code.
The main purpose of having a coding standard is for the code to be as immediately readable as possible to as many potential contributors, and hence most of it focuses on defaulting to coding structures that exist in other similar languages (Java, C#) when possible.
Don't use .let{}
and ?:
Kotlin is made greater for being strict with nullability. Don't let this fact confuse people new to it. These can be simply replaced by if(x!=null)
which is much more readable. They all probably compile to the same bytecode anyway, so when in doubt - readability.
for(item in list)
and not list.forEach{}
For loops go waaaay back, forEach doesn't. As an added bonus, I'm pretty sure that because forEach accepts a function parameter, then when debugging it won't automatically step into these lines, unlike for.
Avoid premature abstraction
There's no need to create an interface if there is only one implementation of that interface. Doing so obfuscates the actual code that's running and increases the Time To Relevant Code. If abstraction becomes necessary later, we can always do it later.