We have a similar setup for extending our app with custom fields / forms using ruby-json-schema and react-jsonschema-form [1]. ruby-json-schema has worked out

We have a similar setup for extending our app with custom fields / forms using ruby-json-schema and react-jsonschema-form [1]. ruby-json-schema has worked out quite well, we added a custom schema reader so that we could generate enums dynamically based on records in the database via custom refs eg. app://schemas/organizations?type_eq=education&tags=one, any of these internal refs are inlined at the API layer. One issue we did run into with ruby-json-schema, is the schema caching is not thread safe. We opted to clear the cache after each validation, this ended up causing race-condition issues. In the end we had to use a mutex on write and cache the validation result (not ideal, but our app isn't that write heavy). [1] https://github.com/mozilla-services/react-jsonschema-form https://github.com/mozilla-services/react-jsonschema-form