---
title: "Federation-Compatible Subgraph Implementations"
canonical: "https://support.apollographql.com/space/ETKB/639139854/Federation-Compatible%20Subgraph%20Implementations"
format: markdown
---
Whenever you encounter a GRAPHQL_VALIDATION_FAILED error it’s important to check the compatibility of the subgraph implementation being used.

Since GraphOS relies on Apollo Federation 2 for core functionality, it is compatible with a wide variety of [servers that support Federation 2](https://www.apollographql.com/docs/federation/supported-subgraphs). You do not need to already be using Apollo Federation in your schema to connect your server to GraphOS.

There is also a [test suite available here](https://github.com/apollographql/apollo-federation-subgraph-compatibility) that will allow you to check if your implementation is compatible.