---
title: Upcoming changes to schema composition for Schema Stitching projects
description:
  Due to stitching limitations we need to slightly alter the schema composition behaviour for more
  predictable results.
date: 2024-02-08
authors: [laurin]
---

Due to limitations within the stitching implementation powered by
[graphql-tools](https://github.com/ardatan/graphql-tools), we are going to slightly alter the
behaviour of the schema composition for better predictability of the schema composition result.

Currently, composition for schema stitching projects can lead to unexpected (seemingly unpredictable
schema changes) appearing when publishing a service schema or running a schema check.

The reason for this is that the composite schema output from the stitching composition
implementation is affected by the order of the input (subgraph) schemas. Today, the input
schemas/subgraphs for the composition are ordered by their creation date (publish date). This means
that each publish/check (unless they are strictly run in the same order), can result in a different
output schema.

Some of you reached out to us because of this confusion and unpredictability.

Due to these limitations, we decided to make subtle changes to the sorting of the input subgraph
schemas in order to make the output composite schema more predictable.

Starting on **20.04.2024,** the subgraphs will always be sorted alphanumerically by their name to
ensure a stable input order across schema publishes and schema checks.

We also recommend everyone that uses the graphql-tools stitching implementation to sort their
schemas alphanumerically by their name in their gateway implementation. The Hive CDN will also serve
the service list in that given order.
