I'd like to get some eyes on this MR, since it's a pretty big rewrite of deku: Impl `from_reader` by wcampbell0x2a · Pull Request #352 · sharksforarms/deku · GitHub.
In particular, i'd like to remove the allocations within https://github.com/sharksforarms/deku/blob/19ee68779f7ba0ef5670a649190ab823456a0e42/src/reader.rs#L143. The BitVec stored in the Reader should somehow always retain the allocation of only 8 bits and read_bits should write the leftover into it, but I can't quite figure it out. At least, I think that will help the performance.