MIGRATING NETFLIX TO GRAPHQL SAFELY

Summary from the TLDR Web Dev newsletter

Netflix migrated their mobile apps to GraphQL in 2022. This was done with zero downtime and involved a total overhaul from the client to the API layer. Doing this safely for 100s of millions of customers without disruption was exceptionally challenging, especially considering the many dimensions of change involved. This blog post shares the broadly-applicable techniques (beyond GraphQL) Netflix used to perform this migration. The three strategies discussed are AB Testing, Replay Testing, and Sticky Canaries. Netflix first created a new GraphQL service over the previous legacy monolith API endpoints. It then deprecated both the service and legacy API in favor of GraphQL services owned by the domain teams.