Blog
Mert Özen's blog posts on software development, backend, frontend, and DevOps.
What Changed in gRPC and GraphQL: From .NET Core 3.0 to .NET 11 and Hot Chocolate 13 to 16
The first things to check in an old gRPC or GraphQL project are Grpc.Core usage and the Hot Chocolate major version: Grpc.Core has been in maintenance mode since 2021, and Hot Chocolate 16 rewrote the scalar API. We show what grpc-dotnet brought from .NET Core 3.0 to .NET 11 and Hot Chocolate from 13 to 16, the same ISBN scalar on both versions, and the September 2025 GraphQL specification, with real output.
Building the Bookstore GraphQL API with Hot Chocolate 16: Schema, EF Core Integration and Mutations
The safe way to connect EF Core in Hot Chocolate 16 is to give every resolver its own DbContext from a pooled factory and to choose deliberately every field, filter and error the schema exposes. We show the random failures of a shared DbContext, the SQL behind projection and sorting, a purchase price leaking from the entity, typed errors with mutation conventions, and onError, all with real output.
GraphQL Fundamentals: Schema, Queries, Mutations, Subscriptions and How Resolvers Work
In GraphQL the client describes what a screen needs in one query and the server resolves each field with its own resolver; this ends over-fetching but brings N+1 and the loss of HTTP caching with it. With Hot Chocolate 16 we show the type system, variables, fragments and aliases, partial data and null propagation, @oneOf from the September 2025 spec and GraphQL over HTTP behaviour with real responses.