Confetti: building a Kotlin Multiplatform conference app in 40min

on YouTube ↗43m

" summary

Live coding produces a working Confetti app end to end: a graphql-kotlin backend serving Kotlinx‑serialized Kotlin models (including a custom LocalDateTime scalar), an Apollo pipeline that generates Kotlin multiplatform models and uses normalized in‑memory and persistent caches, a KMM shared view model exposing StateFlow to Jetpack Compose and SwiftUI via km‑viewmodel/KMP native coroutines, and native Android and iOS apps that mostly run (with one live build hiccup) and are published to the stores.

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" chapters (28)

1. 0:00Introduction
2. 1:05Kotlin Multiplatform and GraphQL overview
3. 2:51Declarative UI with Jetpack Compose & SwiftUI
4. 3:12GraphQL basics and Kotlin integration
5. 5:19Conference app architecture plan
6. 6:23GraphQL backend setup with Kotlin
7. 7:29Spring Boot and Gradle config
8. 8:56GraphQL schema and queries
9. 10:00Backend server and GraphQL Playground
10. 12:10Conference data models with Kotlin serialization
11. 13:58GraphQL schema with nested types
12. 15:43Custom scalar types for dates
13. 17:51Android and iOS clients with shared Kotlin
14. 18:12KMM project structure setup
15. 18:54Kotlin models from GraphQL queries
16. 20:21Shared repository for GraphQL data
17. 21:25Shared ViewModel for UI state
18. 22:49Android UI with Jetpack Compose
19. 24:20Android UI with tabs and sessions
20. 26:03iOS UI with SwiftUI
21. 27:06Shared Kotlin in iOS apps
22. 28:29Query updates and room display
23. 29:53Live demo challenges and fixes
24. 30:14Community contributions and features
25. 31:00Kotlin Multiplatform and GraphQL benefits
26. 32:11Open source project and community
27. 32:54Future plans for web and WebAssembly
28. 33:17Q&A

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