Updating a self-hosted script is always a little nerve-wracking once it's customized and in production. A few habits that make it less scary:
- Always take a full backup (files + database) immediately before updating, not "recently" - immediately.
- Keep custom modifications isolated (a child theme/plugin pattern, or a documented diff) instead of editing core files directly, so updates don't wipe out your changes.
- Read the changelog for breaking changes, especially around database schema or deprecated hooks/functions.
- Update on staging first when possible, even if it's just a quick local copy, before touching production.
- Update in smaller increments rather than jumping many versions at once - it's much easier to isolate what broke.