Error: Required module `Ppx_deriving_yojson_runtime' is unavailable

ppx

#1

Trying to update some dependencies and explore with http-af, I’ve hit this error:

File "_none_", line 1:
Error: Required module `Ppx_deriving_yojson_runtime' is unavailable

In my _tags_ file I have:true: package(yojson,ppx_deriving_yojson)`, and I see that it’s there, and that it’s been there since early 2016 at least, so I don’t understand what I’m missing, or even how to start debugging this.

This is with ocaml 4.04.2, if that helps at all


#2

There’s a ppx_deriving_yojson.runtime package that you need to include.