This is my Rust solution for the CodeCrafter's "Build Your Own DNS server" Challenge.

tl;dr - this was a real challenge with:

• Bit-packing the header, bit shifts and all that.
• Parsing and reading different formats of low-level bytes.
• Rust is a nitpicky language.
• The QNAME pointer requires the full packet to resolve, but my initial implementation consumed a BytesMut via like buf.get_u16() a lot, such that pointers couldn't be resolved in line with the rest of the code. Thinking of a way to defer the pointer resolve was tricky, and I don't really think it's an amazing solution. Much better would be to use a Cursor that allows you to move around the buffer as you go. Maybe in the future.