Calvin Cestari
IOS Engineer at Apollo GraphQL
Vancouver, British Columbia, Canada
Summary
🤩
Rockstar🎓
Top SchoolCalvin Cestari is an iOS engineer and seasoned software leader with 15 years of experience bridging backend systems and mobile platforms, now contributing at staff level to Apollo GraphQL from Vancouver. He has led cross-platform transitions and growth-oriented product teams at Clio, shipping the company’s first client-facing mobile app and establishing a Product Growth team that fused analytics with experimentation. Hands-on and managerial, he still codes—recently enhancing Apollo’s widely used apollo-ios client with support for GraphQL’s @defer directive to improve runtime behavior and maintainability. Known for scaling teams and shipping pragmatic technical changes, he combines deep mobile expertise with a knack for organizational change and data-informed product decisions.
15 years of coding experience
20 years of employment as a software developer
National Diploma, Information Technology, Computer Science, National Diploma, Information Technology, Computer Science at Port Elizabeth Technikon
Github Skills (6)
graphql10
swift10
ios10
mobile-development10
wordpress-graphql10
wpgraphql10
Programming languages (10)
Github contributions (5)
apollographql/apollo-ios
May 2021 - Jan 2023
📱 A strongly-typed, caching GraphQL client for iOS, written in Swift.
Role in this project:
iOS Mobile Developer
iOS Mobile DeveloperContributions:33 releases, 714 reviews, 217 commits in 1 year 8 months
Contributions summary:Calvin's commits primarily focus on enhancing the functionality and maintainability of the Apollo iOS client. They implemented features related to the `@defer` directive support, enabling features within the Apollo iOS client related to the defer directive. These changes included modifying the `DataDict` and `Selection` structures, as well as updating the `GraphQLExecutor` to properly handle the defer directive.
graphql-clientapollographqlcachingapollo-iosstrongly-typed
apollographql/apollo-ios-dev
Aug 2023 - Mar 2025
Apollo iOS Development Repo
Contributions:391 reviews, 464 PRs, 549 pushes in 1 year 7 months
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