File Viewers

A cross-platform desktop app for viewing and editing Markdown, MDX, JSON, CSV, Excel, and Parquet files. Built with Tauri 2 + React 19.

Features

• Multi-tab file management with session persistence across restarts
• Markdown / MDX viewer with GFM, tables, and syntax-highlighted code blocks
• JSON tree viewer with collapsible nodes and dark/light theme support
• CSV and Excel viewer — sortable columns, global search, in-browser SQL queries; cell editing with copy/cut/paste/delete, undo/redo history, multi-cell selection (click-drag and Cmd+click), column context menu (sort, select, delete), and row split/merge
• Parquet viewer powered by DuckDB-WASM — query large files entirely in-browser
• Monaco editor for Markdown and JSON with live preview
• Command palette (Cmd+K) — open local files or load any file by URL
• File tree sidebar for navigating all open tabs
• Auto-updater — checks for new releases on startup with an in-app install prompt
• Drag-and-drop file loading
• System / Light / Dark theme

Prerequisites

• Rust (stable toolchain)
• Bun >= 1.0

Platform support: macOS 12+, Linux (GTK), Windows 10+

Development Setup

cd apps/desktop-app
bun install
bun run tauri dev

Other commands

bun run tauri build   # production bundle for current platform
bunx tsc --noEmit     # type check only

Tech Stack

Layer	Library
App shell	Tauri 2
UI	React 19 + TypeScript
Build	Vite 7 + Tailwind CSS 4
State	Zustand
Editor	Monaco Editor (local bundle, no CDN)
Markdown	react-markdown + remark-gfm + rehype-highlight
JSON	react-json-view-lite
CSV / Excel	TanStack Table v8 + PapaParse
Parquet	DuckDB-WASM (in-browser query engine)
SQL mode	alasql (in-memory SQL on csv table)
Icons	Hugeicons
UI primitives	shadcn/ui + Radix

Project Structure

file-viewers/
├── apps/
│   ├── desktop-app/        # Tauri + React desktop application
│   │   ├── src/
│   │   │   ├── App.tsx
│   │   │   ├── components/
│   │   │   │   ├── table/      # DataTable, Header, Toolbar, ContextMenu, StatusBar, VirtualRow, SearchInput, SqlInput
│   │   │   │   ├── toolbar/    # Toolbar, ToolbarActions, FormatTabs
│   │   │   │   ├── ui/         # Button, Input, Dialog, and other primitives
│   │   │   │   └── workspace/  # FileTree sidebar
│   │   │   ├── hooks/
│   │   │   ├── store/          # Zustand store
│   │   │   └── utils/
│   │   ├── src-tauri/
│   │   │   ├── src/lib.rs
│   │   │   ├── tauri.conf.json
│   │   │   └── capabilities/
│   │   └── docs/           # Architecture + component reference
│   └── landing/            # TanStack Start landing page (Cloudflare Workers)
└── scripts/

Supported Formats

Extension	Viewer
.md, .markdown, .mdx, .txt	Markdown
.json	JSON tree
.csv	CSV table + SQL
.xlsx	Excel table + SQL
.parquet	Parquet table (DuckDB-WASM)

License

MIT — see LICENSE

Docs

• apps/desktop-app/docs/architecture.md — component hierarchy, state, file loading, theme system, Tauri capabilities
• apps/desktop-app/docs/components.md — props reference for every component