The actual name of the package is type_conv
(https://github.com/janestreet/type_conv). Having it named
ocaml_typeconv adds a verbosity that isn't required and actually makes
the package harder to find.
This library defines a syntax extension for OCaml using Camlp4 that
can be used to define first class values representing record fields,
and additional routines, to get and set record fields, iterate and
fold over all fields of a record and create new record values.
Homepage: https://ocaml.janestreet.com/