Jits Builder

Instantly build, deploy, and access single-page, vanilla JS mini-apps from voice or text descriptions via a Cloudflare tunnel URL.

Danny Shmueli@dannyshmueli

Install

openclaw skills install @dannyshmueli/jits-builder

JITS Builder - Just-In-Time Software 🚀

Build instant mini-apps from voice or text descriptions. Describe what you need, get a working tool deployed in seconds.

What is JITS?

Just-In-Time Software - the idea that you don't need to find or install tools. You describe what you need and it gets built on the spot.

"I need a timer that plays a sound after 25 minutes" "Make me a tool to split a bill between friends"
"Create a page where I can paste JSON and see it formatted"

Requirements

Cloudflared binary (auto-downloads to /tmp/cloudflared if missing)
Node.js (for serving the app)

How It Works

Describe - Voice or text, explain what you want
Generate - Agent builds a single-file HTML/JS/CSS app
Deploy - Cloudflare tunnel makes it instantly accessible
Use - Get a URL, use your tool, share it

Usage

Just ask naturally:

text

"Build me a pomodoro timer"
"I need a quick tool to convert CSV to JSON"
"Make a tip calculator"
"Create a color palette generator"

The agent will:

Generate the HTML/JS code
Save to /data/clawd/jits-apps/<name>.html
Serve on a local port
Create Cloudflare tunnel
Return the public URL

Managing JITS Apps

bash

# List running apps
/data/clawd/skills/jits-builder/jits.sh list

# Stop an app
/data/clawd/skills/jits-builder/jits.sh stop <name>

App Guidelines

When building JITS apps:

Single file - All HTML, CSS, JS in one file
No dependencies - Use vanilla JS, no external libraries
Mobile-friendly - Responsive design
Dark theme - Looks good, easy on eyes
Self-contained - No backend/API calls needed
Branded - Include "Built with JITS" badge

Template Structure

html

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>🚀 JITS - [App Name]</title>
  <style>
    /* Dark theme, centered layout */
    body {
      font-family: -apple-system, sans-serif;
      background: linear-gradient(135deg, #1a1a2e, #16213e);
      min-height: 100vh;
      display: flex;
      align-items: center;
      justify-content: center;
      color: white;
    }
    /* ... app styles ... */
  </style>
</head>
<body>
  <div class="container">
    <h1>[App Title]</h1>
    <div class="badge">Built with JITS</div>
    <!-- App content -->
  </div>
  <script>
    // App logic
  </script>
</body>
</html>

Example Apps

App	Description
Pomodoro Timer	25/5 min work/break cycles with sound
Tip Calculator	Split bills with custom tip %
JSON Formatter	Paste JSON, see it pretty-printed
Color Picker	Generate and copy color palettes
Countdown	Timer to a specific date/event
QR Generator	Text to QR code
Unit Converter	Length, weight, temperature
Decision Maker	Random picker for choices

Limitations

Single-page only - No multi-page apps
No backend - Client-side only, no databases
Temporary URLs - Tunnels expire when stopped
No persistence - Data doesn't survive refresh (use localStorage if needed)

Directory Structure

text

/data/clawd/jits-apps/
├── pomodoro.html      # App HTML
├── pomodoro.pid       # Server process ID
├── pomodoro.port      # Port number
├── pomodoro.url       # Tunnel URL
└── pomodoro.tunnel.pid # Tunnel process ID

"The best tool is the one you build exactly when you need it." 🐱🦞