+### Adding new sources or PPAs
+
+If you are adding a new source or PPA and trying to install packages from the new source or PPA on the same Puppet run, your `package` resource should depend on `Class['apt::update']`, in addition to depending on the `Apt::Source` or the `Apt::Ppa`. You can also add [collectors](https://docs.puppetlabs.com/puppet/latest/reference/lang_collectors.html) to ensure that all packages happen after `apt::update`, but this can lead to dependency cycles and has implications for [virtual resources](https://docs.puppetlabs.com/puppet/latest/reference/lang_collectors.html#behavior).
+
+~~~puppet
+Class['apt::update'] -> Package<| |>
+~~~
+