There are multiple ways to install and run scripts in RunJavaScript. Here are some samples:
- Use Shortcuts action to create x-callback-url
- Use Shortcuts to open scripts and integrate. See this page
- Use in-line editor and edit manually
- Use IOS Files app to copy files from other apps
- Use other apps like Working Copy to edit and store scrips. See this page.
- Use integrated webdav server to mount documents directory on your laptop, use git, node.js etc. to build.