# Migrating from Apollo Tooling to GraphQL Codegen at Yelp

[Yelp](https://yomu.fyi/company/yelp) · Igor Kusakov, Software Engineer · Jul 16, 2026

**Type:** Problem & solution

## Summary

Yelp migrated its frontend React monorepo from the deprecated apollo-tooling to GraphQL Codegen to ensure ongoing maintenance and build reliability. Because the monorepo spans over 500 packages with thousands of generated type files and custom nested type imports, the Client Data team prioritized a transparent migration that avoided codebase-wide changes. The team rejected approaches requiring syntax updates or altered import paths, choosing instead to configure GraphQL Codegen and contribute upstream plugin changes so output structures and naming conventions matched the legacy output. Migrating packages incrementally through small pull requests enabled continuous feedback while allowing developers across dozens of teams to maintain their workflows without editing existing code. Completing the migration to GraphQL Codegen v6 simplified Yelp's build tooling, eliminated deprecated dependencies, and left upstream compatibility enhancements available for the wider open-source community.

## Context

Yelp relied on apollo-tooling to generate TypeScript types from GraphQL queries and mutations in its React monorepo. In April 2023, Apollo deprecated its CLI service commands and recommended migrating to GraphQL Codegen. With apollo-tooling reaching end of life, existing bugs were no longer resolved and diagnosing issues became difficult, requiring Yelp to adopt a supported replacement.

## Approach / What changed

Yelp's Client Data team configured GraphQL Codegen to replicate apollo-tooling's output patterns, such as query-based file naming and inlined schema types, preserving thousands of existing imports across 500+ packages. Rather than relying on fragile post-processing scripts, the team upstreamed configuration capabilities to GraphQL Codegen plugins and migrated packages incrementally in batches to validate stability before removing the legacy tooling.

## Takeaways

- Transparent tooling migrations in large monorepos prevent disruption across dozens of teams by keeping file structures and type signatures backwards-compatible.
- GraphQL Codegen default outputs diverged from apollo-tooling by using component-named files, external globalTypes imports, and combined field-and-type nested type names.
- Upstreaming custom plugin improvements to open-source dependencies eliminates private maintenance overhead and ensures long-term upgrade compatibility.

**Tags:** [Developer Experience](https://yomu.fyi/topic/developer-experience), [GraphQL](https://yomu.fyi/topic/graphql), [Migrations](https://yomu.fyi/topic/migration), [Open Source](https://yomu.fyi/topic/open-source), [TypeScript](https://yomu.fyi/topic/typescript)

[Read original post](https://engineeringblog.yelp.com/2026/07/migrating-to-graphql-codegen.html)