Is there a piece of official text that mentions th...

# k2-adopters

[Edoardo Luppi]

Is there a piece of official text that mentions the compatibility of libraries compiled with K2 and consumed by K1?

[dmitriy.novozhilov]

Forward compatibility rules weren't affected by the K2 compiler
• Binaries produced by 2.0.x compiler with LV 2.0 can be consumed by 1.9.x compiler (but not 2.1.x and LV 2.1)
• If LV is set to lesser version, then binaries will be compatible with LV-1 compiler version

[dmitriy.novozhilov]

LV is the language version

[Edoardo Luppi]

Thanks!
> Binaries produced by 2.0.x compiler with LV 2.0 can be consumed by 1.9.x compiler
So the cap is at 2.0.x? Starting from 2.1.x (with LV 2.1), 1.9 won't be able to reliably consume them?

[dmitriy.novozhilov]

Yep
That's the same as with all previous releases
Forward compatibility always was up to one version

[Pavel Kunyavskiy [JB]]

Just in case, this is for JVM binaries. For klib-based backends (all except jvm), we never explicitly supported forward compatibility. 1.9 would probably work with 2.0.20 for js/native/wasm. But this was not tested.

[Edoardo Luppi]

Do you think you'll get to a point where the same behavior could be applicable to all backends?

[Pavel Kunyavskiy [JB]]

Eventually yes, but not in plans right now.