Valdi – A cross-platform UI framework that delivers native performance

Original Article ↗ Hacker News Discussion ↗

Overview and Goals

  • Valdi is presented as a declarative TypeScript UI framework that renders to native views on iOS, Android, and macOS, aiming for “write once” UI with native performance and no webview/bridge.
  • Some commenters are excited to see a polished internal Snap framework finally open-sourced, but others want more real-world examples, components, and screenshots before taking it seriously.

Architecture and TypeScript Compilation

  • Under the hood it uses native views, conceptually similar to React Native.
  • There are three execution modes for TS:
    • Interpreted JS,
    • JS bytecode,
    • AOT TS→C compilation.
  • The AOT compiler reportedly supports most of TS/JS, including a limited eval, but currently trades larger binaries for modest and inconsistent performance gains; it’s described as a work in progress.
  • State is handled via class-style components reminiscent of pre-hooks React.

Comparison with Other Frameworks

  • Frequently compared to React Native and ByteDance’s Lynx.js: same general idea (React-style TS → native views, multiple execution modes).
  • Some see Valdi’s ideas (AOT options, debugging, native bindings) as parallel to or converging with recent React Native improvements.
  • Others note the lack of Swift/SwiftUI, Linux, Windows, and HTML targets as a major limitation.

Snapchat’s Track Record and Camera Tradeoffs

  • Skepticism arises from Snapchat’s historically poor Android experience, especially the “screenshot of camera preview” approach.
  • Multiple commenters familiar with mobile camera stacks argue that this was a pragmatic tradeoff given old Android hardware, fragmented camera APIs, and Snapchat’s need for near-zero shutter delay.

Native vs WebView vs Cross-Platform

  • Large subthread debates whether frameworks like Valdi are worthwhile versus:
    • Fully native per-platform UIs with a shared core,
    • Hybrid/WebView apps (Cordova/Ionic/Capacitor/Tauri),
    • Alternatives like Flutter, Kotlin Multiplatform, Qt/QML, SwiftUI.
  • Many report hybrid apps often feel “off” or sluggish, but some claim well-done WebView apps can be indistinguishable from native for many use cases.
  • Several note that AI/codegen doesn’t remove deep architectural and platform constraints (e.g., App Store policies, native integrations).

UX and Ecosystem Concerns

  • Opinions on Snapchat’s UX are polarized: some call it confusing, manipulative, and ad-heavy; others see it as a major UX innovator copied by nearly every social app and intuitive for younger users.
  • Some worry Valdi’s codebase looks over-engineered for solo or small-team use and that in-house BigTech frameworks tend to be moving targets.
  • Using Discord as the primary community channel draws criticism for being closed, hard to search, and privacy-unfriendly.