/opentui

React Configuration

Project Setup

Quick Start

bunx create-tui@latest -t react my-app
cd my-app && bun install

The CLI creates the my-app directory for you - it must not already exist.

Options: --no-git (skip git init), --no-install (skip bun install)

Manual Setup

mkdir my-tui && cd my-tui
bun init
bun install @opentui/react @opentui/core react

TypeScript Configuration

tsconfig.json

{
  "compilerOptions": {
    "lib": ["ESNext", "DOM"],
    "target": "ESNext",
    "module": "NodeNext",
    "moduleResolution": "NodeNext",
    
    "jsx": "react-jsx",
    "jsxImportSource": "@opentui/react",
    
    "strict": true,
    "skipLibCheck": true,
    "noEmit": true,
    "types": ["bun-types"]
  },
  "include": ["src/**/*"]
}

Critical settings:

• jsx: "react-jsx" - Use the new JSX transform
• jsxImportSource: "@opentui/react" - Import JSX runtime from OpenTUI
• module / moduleResolution: "NodeNext" - Recommended for OpenTUI compatibility

Why DOM lib?

The DOM lib is needed for React types. OpenTUI's JSX types extend React's.

Package Configuration

package.json

{
  "name": "my-tui-app",
  "type": "module",
  "scripts": {
    "start": "bun run src/index.tsx",
    "dev": "bun --watch run src/index.tsx",
    "test": "bun test",
    "build": "bun build src/index.tsx --outdir=dist --target=bun"
  },
  "dependencies": {
    "@opentui/core": "latest",
    "@opentui/react": "latest",
    "react": ">=19.0.0"
  },
  "devDependencies": {
    "@types/bun": "latest",
    "@types/react": ">=19.0.0",
    "typescript": "latest"
  }
}

Project Structure

Recommended structure:

my-tui-app/
├── src/
│   ├── components/
│   │   ├── Header.tsx
│   │   ├── Sidebar.tsx
│   │   └── MainContent.tsx
│   ├── hooks/
│   │   └── useAppState.ts
│   ├── App.tsx
│   └── index.tsx
├── package.json
└── tsconfig.json

Entry Point (src/index.tsx)

import { createCliRenderer } from "@opentui/core"
import { createRoot } from "@opentui/react"
import { App } from "./App"

const renderer = await createCliRenderer({
  exitOnCtrlC: true,
})

createRoot(renderer).render(<App />)

App Component (src/App.tsx)

import { Header } from "./components/Header"
import { Sidebar } from "./components/Sidebar"
import { MainContent } from "./components/MainContent"

export function App() {
  return (
    <box flexDirection="column" width="100%" height="100%">
      <Header />
      <box flexDirection="row" flexGrow={1}>
        <Sidebar />
        <MainContent />
      </box>
    </box>
  )
}

Renderer Configuration

createCliRenderer Options

import { createCliRenderer, ConsolePosition } from "@opentui/core"

const renderer = await createCliRenderer({
  // Rendering
  targetFps: 30,
  
  // Behavior
  exitOnCtrlC: true,        // Set false to handle Ctrl+C yourself
  autoFocus: true,          // Auto-focus elements on click (default: true)
  useMouse: true,           // Enable mouse support (default: true)
  
  // Debug console
  consoleOptions: {
    position: ConsolePosition.BOTTOM,
    sizePercent: 30,
    startInDebugMode: false,
  },
  
  // Cleanup
  onDestroy: () => {
    // Cleanup code
  },
})

Building for Distribution

Bundling with Bun

// build.ts
await Bun.build({
  entrypoints: ["./src/index.tsx"],
  outdir: "./dist",
  target: "bun",
  minify: true,
})

Run: bun run build.ts

Creating Executables

// build.ts
await Bun.build({
  entrypoints: ["./src/index.tsx"],
  outdir: "./dist",
  target: "bun",
  compile: {
    target: "bun-darwin-arm64",  // or bun-linux-x64, etc.
    outfile: "my-app",
  },
})

Environment Variables

Create .env for development:

# Debug settings
OTUI_SHOW_STATS=false
SHOW_CONSOLE=false

# App settings
API_URL=https://api.example.com

Bun auto-loads .env files. Access via process.env:

const apiUrl = process.env.API_URL

React DevTools

OpenTUI React supports React DevTools for debugging.

Setup

1. Install DevTools as a dev dependency (must use version 7):

   bun add react-devtools-core@7 -d

2. Run DevTools standalone app:

   npx react-devtools@7

3. Start your app with DEV=true environment variable:

   DEV=true bun run src/index.tsx

Important: Auto-connect to DevTools ONLY happens when DEV=true is set. Without this environment variable, the DevTools connection code is not loaded.

How It Works

OpenTUI checks for process.env["DEV"] === "true" at startup. When true, it dynamically imports react-devtools-core and connects to the standalone DevTools app.

Testing Configuration

Test Setup

// src/test-utils.tsx
import { createTestRenderer } from "@opentui/core/testing"
import { createRoot } from "@opentui/react"

export async function renderForTest(
  element: React.ReactElement,
  options = { width: 80, height: 24 }
) {
  const testSetup = await createTestRenderer(options)
  createRoot(testSetup.renderer).render(element)
  return testSetup
}

Test Example

// src/components/Counter.test.tsx
import { test, expect } from "bun:test"
import { renderForTest } from "../test-utils"
import { Counter } from "./Counter"

test("Counter renders initial value", async () => {
  const { snapshot } = await renderForTest(<Counter initialValue={5} />)
  expect(snapshot()).toContain("Count: 5")
})

Common Issues

JSX Types Not Working

Ensure jsxImportSource is set:

{
  "compilerOptions": {
    "jsx": "react-jsx",
    "jsxImportSource": "@opentui/react"
  }
}

React Version Mismatch

Ensure React 19+:

bun install react@19 @types/react@19

Module Resolution Errors

Use moduleResolution: "bundler" for Bun compatibility.