Cross-Platform Messaging Experience
Article Summary
Snap rewrote their entire messaging system in C++ to solve a problem that plagues most mobile teams: platform inconsistency causing bugs and doubled engineering effort.
Two years ago, Snap's messaging team embarked on a complete rewrite to improve performance, cut infrastructure costs, and eliminate behavior differences between Android and iOS. Their solution? Build once in C++ instead of maintaining two separate codebases.
Key Takeaways
- Single C++ codebase handles all messaging logic for both iOS and Android
- Used Djinni to generate consistent Java, Objective-C, and C++ interfaces automatically
- Built cross-platform gRPC client with Cronet and QUIC for identical network behavior
- SQLite provides consistent data storage and schema across both platforms
- Small C++ team now maintains what previously required separate iOS and Android teams
Critical Insight
By investing in consistency at every layer (logic, interfaces, networking, storage), Snap ships messaging features faster with fewer bugs and lower maintenance costs.
