A small companion post to my Ghost on Fly tutorials:

You’ve gotten your site all set up on Fly’s free tier, and it’s looking spiffy. But the Ghost developers move fast, and next thing you know there’s a new version out — and it has a feature you want, or a critical security update. How do we update a Ghost site on Fly?

As it turns out, quite simply!

1. Backup your site! Don’t skip this step.
2. Run fly deploy from the directory containing your fly.toml. Or, run fly deploy -a APPNAME from anywhere, replacing APPNAME with (duh) your Fly app name.

What does this do? It creates a new Fly “release”. Since we’re using the community-maintained Ghost docker image, when a new release is deployed, it will pull the latest image with the specified tag from the Docker Hub.

We’re using the 5-alpine tag. This means every time we deploy, we get the latest Ghost 5 image. When Ghost 6 is released, we’ll have to update the image tag; we won’t want to automatically update to Ghost 6, since it may have breaking changes. If you want to pin your blog at a specific version for some reason, you can use the tag for a more-specific version number (for example, 5.29-alpine or 5.29.0-alpine).

Note: the Ghost Docker image is officially an unofficial way of running Ghost, and updates to the docker image generally land a few hours or days after Ghost updates are released.

If you’re running Ghost + MySQL on Fly (as opposed to Ghost + SQLite), you’ll probably also want to fly deploy the latest MySQL 8 docker image to your database instance once in a while.