create_launcher

Create Launcher (Web & Scripts)

Use this skill to generate professional-grade entry point scripts for applications.

Inputs

• App Name: Name of the application (for display).
• Entry Point: Main script to run (e.g., main.py, index.js).

Tooling Strategy

• Use write_to_file to create the scripts.
• Use run_command with pwsh (Windows) or bash (Unix) to verify dependency checks if needed.

Workflow

1. Requirements Gathering

• Target OS: Windows, macOS, Linux (default to creating for ALL).
• Environment: Does it need .env variables?
• Dependencies: What needs to run? (npm, python, node, docker).

2. Script Generation Rules

Common Features

• Single Click Launch: Scripts must run without user argument input (or have defaults).
• Pre-flight Checks:
  • Check if required tools (node, python) are in PATH.
  • Check if node_modules or venv exists.
  • Check for .env file presence.

Windows (.bat / .cmd)

• Use @echo off.
• Title the window.
• Handle Ctrl+C gracefully if possible.

Unix (.sh for Mac/Linux)

• Shebang: #!/bin/bash.
• Permission: Remind user to chmod +x.
• Trap Signals: Implement trap 'kill 0' SIGINT or similar to clean up subprocesses on exit.

3. Graceful Shutdown (The "No Orphan" Rule)

• Ensure that killing the launcher kills the spawned processes.
• For python scripts, consider wrapping in try-finally blocks.

4. Output

• Generate the scripts in the project root.
• Provide a quick Markdown snippet on how to run them.

Advanced Launcher Patterns

When generating launchers, consider these enterprise patterns:

• Environment Portability: Ensure the script runs correctly regardless of the current working directory by resolving paths relative to the script itself (cd "%~dp0" on Windows, cd "$(dirname "$0")" on Unix).
• Daemonization & Logging: Offer the option to run the application in the background and pipe stdout/stderr to a dedicated logs/ directory with timestamped files.
• Health Checks: After starting the process, optionally ping an endpoint or check a port to confirm the app is actually running before exiting the launcher.