If you work with library data, you work with MARC21 — the length-prefixed binary record format catalogues have run on since the 1960s, complete with a directory of field offsets, subfield delimiters, and a pre-Unicode character encoding called MARC-8 that needs a lookup table with thousands of entries to decode. In Python that problem is solved: pymarc is mature, complete, and pleasant to use. In Go it wasn't. gomarc is a port of pymarc to Go. It covers the binary MARC21 transm...