Lov — Large object viewer

A fast, browser-based viewer for large structured data files.
Rust/WASM handles parsing; React virtualizes the tree so only visible rows render.

Features

• Formats: JSON, JSON5, YAML, TOML, CSV
• Input: drag-and-drop, file picker, or fetch from a URL
• Virtualized tree — renders only what's on screen; handles large files without freezing
• Collapsible nodes — click any row to toggle subtrees
• Dark mode — persisted in localStorage
• Data samples — 6 different examples hosted by the JSON placeholder api

Stack

Tech	Layer
React 19, TypeScript, Tailwind CSS 4, DaisyUI 5	UI
Rust compiled to WASM (wasm-bindgen)	Parsing / rendering
@tanstack/react-virtual	Virtualization
Vite 8, Bun	Build

Getting started

# Install dependencies
bun install

# Dev server
bun run dev

# Production build
bun run build

Requirements: wasm-pack must be installed — Vite compiles the Rust crate automatically on dev/build.

cargo install wasm-pack
# or
npm i -g wasm-pack
# or
bun i -g wasm-pack

Project layout

src/
  components/   React components (MainPage, ViewerPage, Upload, …)
  hooks/        useDragDrop
  utils/        WASM loader helpers
  worker/       Web Worker + WASM bridge
rs/
  src/          Rust source (parsers, viewer, tree logic)
  pkg/          Pre-built WASM output

Supporting

Lov is free and open source (MIT).
If it saves you time, consider sponsoring me or starring this repo.

License

MIT © 2026 Bishops-exe