Change your app after it is online

This page helps you change your app once it's online: a new feature, a fix, new words on a page. It explains what to ask Claude Code, what happens to the version people are using while the new one gets ready, what stays the same, and how to put an earlier version back if the change goes wrong.

1. Make the change on your computer

Work with Claude Code in your project folder as usual, and check the change works in the preview on your computer first. fline puts online what's in your folder, so what you see there is what you'll get.

2. Ask Claude Code to update your app

Update my app on fline with the changes I just made.

Claude Code packs up your project folder again and sends it to fline. fline reads it and gets the new version ready, the same way as the first time. You'll see it on your fline dashboard, and fline emails you when the build starts and when it's live.

What happens to the version people are using

The current version keeps running while the new one is prepared. People who open your link keep seeing your app as it was.

When the new version is ready, it takes the old one's place, at the same link.

If fline can't build the new version, the version already online keeps running. Your dashboard and Claude Code say what went wrong, so you can try a fix and update again.

What stays the same

• Your database and everything in it. It belongs to your account, not to one version of your app.
• Your passwords and keys. If the new version needs a new key, Claude Code gives you a private page for it. See Passwords and keys your app uses.
• Your web address and your long link.

If your app says a key is missing after an update, ask Claude Code:

After the update, my app on fline says a key is missing. Check which keys fline has for my app and tell me what's needed.

Keep the same plan every time

The first time, fline reads your project and works out how to build and run it. You can ask Claude Code to save that plan in your project, in a file called fline.json, and later updates follow the same plan.

Save fline's build plan in this project, so later updates follow the same plan.

If you later change how your app is built, for example by adding a new part to it, Claude Code can update the plan too.

Put an earlier version back

If an update broke something, ask Claude Code to go back to an earlier version.

The last update on fline broke my app. Show me the earlier versions and put back the one from before it.

Claude Code can list the versions fline has kept, with when each was made, and put back the one you choose. fline runs exactly what ran then, as a new version, and keeps your current passwords and keys. So the version number goes up, not down. That's expected.

Some things to know:

• There's no button on your dashboard for this yet. Ask Claude Code.
• It doesn't change your database. Anything your app saved since stays saved, and anything it deleted stays deleted.
• It doesn't bring back old keys. Your current keys stay in place.
• If an old version can't be used any more, fline refuses and says why, rather than running something close to it.
• Your project folder doesn't change. The earlier version is back online, but the files on your computer still have the newer code. Ask Claude Code to fix the problem there before your next update.

Things to say to Claude Code

Update my app on fline with the changes I just made.

The last update on fline failed. What went wrong? Try a fix, or put the earlier version back.

What versions of my app does fline have, and which one is running now?

Next: When something goes wrong or Passwords and keys your app uses