A native Twitch chat client for iPhone, built for the pace of a live stream.
2,700 active usersSeptember 2026; 4.7 stars on the App Store
Live chat combines sustained message traffic, image-heavy content, and a UI people expect to scroll smoothly. I build the native app and its release workflow, including chat, moderation tools, third-party emotes, accessibility, widgets, Live Activities, and Siri Shortcuts.
I build it with AI coding agents and my own review plugins: ios-code-review reviews every pull request that changes code, and apple-ui-craft reviews interface and accessibility work.
Per-channel ring buffers overwrite at capacity in O(1). Observer updates are batched, and a collection-view engine handles visible chat. Keeping the latest conversation useful does not require retaining an unbounded transcript in memory.
Swift 6 strict concurrency separates network and IRCv3 parsing from main-actor UI state. That boundary makes ownership explicit and keeps incoming traffic from turning every parsed message into immediate UI work.
The emote pipeline shares in-flight downloads and caps its caches at 48 MB in memory and 200 MB on disk. Widgets read a snapshot the app writes to a shared App Group, and the app updates Live Activities on the device, so the extensions never touch the network.
How a chat message reaches the screen.
SwiftUI provides the application structure; the chat surface uses a collection-view engine where scrolling and reuse need closer control. Native integration and accessibility remain part of the same product, including VoiceOver, Dynamic Type, and Reduce Motion.
More engineering work