graphql_ppx was forked from mhallin/graphql_ppx at tag 0.2.9.
A number of changes were made atop that, including support for
compilation with Bazel.
For OCaml 4.11.2, some additional changes were made due to changes in the OCaml AST structure.
The library has more recent versions than 0.2.9, but the code is written in Reason, and not in OCaml.