Greets,
I've been looking over
https://github.com/Sereal/Sereal but there is no LICENSE file or other indication I can find at a high-level of the license for the code.
I think it would be helpful to declare the license very visibly up top, and to specify which version of the license(s) you are using. Specifically, Artistic 2.0 is more friendly with copyleft licenses like Apache, MIT, BSD, etc.
I know many open source developers don't care about licensing stuff, and I used to be one of them, but things like this can make a difference for other projects adopting your code. I work with Apache Lucy and would like to experiment with Sereal; GPL and Apache don't play well though, so it's a non-starter based on licensing.
Thanks for the consideration.