Mixins are not classes. I didn't realize this until very recently, so Krypton has some bugs around memory management, including leaking native memory for libdeflate peer objects and not allocating the optimal amount of storage for compressed buffers. We will need to rectify this ASAP.

This came up in the course of my zstd testing.

I will probably fix this by removing PacketDeflaterMixin and PacketInflaterMixin and instead adding handlers from Velocity instead.