Hot Chocolate

Hot Chocolate is a self-hosted GraphQL server built for .NET teams working in ASP.NET Core. It is a strong fit for developers who want schema control in C# and a free, commercially usable server. The trade-off is operational responsibility: your team runs and maintains the service.

Overview

Hot Chocolate turns C# types and resolvers into a typed GraphQL schema, with implementation-first and code-first approaches. It implements the GraphQL 2025 specification and GraphQL over HTTP, and supports spec-compliant clients including Strawberry Shake, Relay and Apollo Client. That makes it a flexible server-side choice for .NET applications without locking clients to a particular vendor.

Self-hosting gives teams control over deployment, but also means they own the runtime and its operation. The getting-started tutorial requires the .NET 8 SDK or later and guides developers to a running server. Its MIT license permits commercial and private use, modification and distribution.

Key features

Transport and schema tools

HTTP and WebSocket cover common request patterns, while Server-Sent Events support streaming responses. Developers can download schemas, use the Nitro GraphQL IDE endpoint and export schemas through a command-line interface. These options help with inspection and tooling, though they do not remove the need to operate the server itself.

Data loading and integrations

DataLoader and batch resolvers group related fetches and cache requests, addressing the N+1 problem that can otherwise make GraphQL queries expensive. Documented integrations include Entity Framework, MongoDB and Marten, which give teams using those data stores a direct path to connect their data layer.

Security and observability

For public APIs, the security guidance recommends cost analysis alongside pagination limits, execution-depth limits and timeouts. Private APIs can use trusted documents to restrict requests to operations registered with the server, a practical safeguard for services used by known clients such as an organization's own applications. Authentication and authorization are also covered.

OpenTelemetry instrumentation spans the server, execution engine and DataLoader layers, including request, resolver and DataLoader spans. This offers useful visibility into GraphQL behavior for teams already working with OpenTelemetry, but instrumentation is not a substitute for operating and securing the service.

Federation and uploads

A Hot Chocolate server can serve as a Fusion subgraph, supporting composition behind a gateway when teams need independent ownership and deployment. File uploads are supported through the Upload scalar, but uploads through a gateway to stitched services are not supported. That limitation makes Hot Chocolate a poorer fit when gateway-mediated file handling is a requirement.

Pricing

The Hot Chocolate plan costs nothing and is MIT licensed for commercial or private projects. There are no paid software tiers to compare; the cost advantage comes with self-hosting, so teams still need to account for running the server themselves.

ChilliCream offers free community support and paid support plans starting at $450 per month for Startup, including two critical incidents. That support option may suit teams that need a formal escalation path, while the free community option fits teams comfortable relying on community help.

Platforms

Hot Chocolate is a self-hosted API server for C# on ASP.NET Core, with web support and an API explorer. Its operation testing capability supports development workflows, but the server is not a hosted service that removes deployment duties.

Who it's for

Choose Hot Chocolate if your team builds .NET services and wants to author GraphQL schemas in C#, use DataLoader to manage related fetches, and retain control of hosting. It is less suitable when you need a managed server or must route uploads through a gateway to stitched services.

Pros and cons

• Pros: MIT-licensed and free for commercial or private projects, with implementation-first and code-first schema options.
• Pros: DataLoader, batch resolvers and documented database integrations help address common data-fetching needs in GraphQL services.
• Pros: OpenTelemetry spans and documented query safeguards support observability and API protection.
• Cons: Self-hosting leaves deployment and ongoing operation to your team.
• Cons: Gateway uploads to stitched services are not supported, which can block a specific file-handling architecture.

Alternatives

Explore GraphQL Tools for a broader directory of GraphQL software. Choose Altair GraphQL Client when you need a client and query workspace rather than a .NET server; its Basic plan allows up to two team members and 20 queries. Apollo Studio is an option for teams seeking Apollo's platform, with a free plan capped at three developers and a router limited to 60 requests per minute.

Apollo Client is a client-side alternative, not a server replacement; its free plan includes up to three developers and a self-hosted GraphOS Router limited to 60 requests per minute. Consider Hasura if its free plan's project-based allowance suits your needs: two databases per project, up to 100MB data passthrough per month and up to 3M API requests per month. Ariadne is another free GraphQL option, without enough detail here to compare its capabilities.

GraphiQL is better suited to teams seeking an MIT-licensed GraphQL package for React applications than a .NET server. GraphQL Hive may fit teams focused on schema and operation usage monitoring, with a free Hobby plan that includes 1M operations per month, seven-day usage-data retention and unlimited seats, projects, organizations and schema pushes. Lighthouse is a free installable PHP package requiring a Laravel or Lumen project, making it a language- and framework-specific alternative.

Verdict

Hot Chocolate is a compelling choice for ASP.NET Core teams that want a capable, MIT-licensed GraphQL server with C# schema authoring, data-loading tools and OpenTelemetry instrumentation. Choose it for control and a zero software price; look elsewhere if you need managed hosting or gateway uploads to stitched services.