Semantic Nullability: A Path Toward Safe Non-Null Fields

Jordan EldredgeMeta, Software Engineer

One of GraphQL’s killer features is field-granular error handling which can dramatically increase the resiliency of network responses. However, this has traditionally come at the cost of developer ergonomics, with client developers being forced to contend with nearly every field potentially being null. In the last year, members of the Nullability Working Group, and engineers at Meta have been exploring how we can untangle nullability and error handling in order to safely allow clients to “see” the true nullability of the server’s resolvers without sacrificing response residency. In this talk we’ll explain the ideas and RFCs that underpin this change, share the work we’ve done at Meta and across the community to validate this approach, and demonstrate Semantic Nullability in action!