UPDATE - Jan 1, 2023: The Atom Editor has sunset, see the official Sunsetting Atom page. Tidal has adopted Pulsar. Tidalcycles is integrated with the Pulsar Package Manager, which supports installation and updating the tidal plugin from within Pulsar. (There is no longer a need for manual plugin install.)
See the documentation on how to use Tidal with Pulsar.
Note: Tidal users who have a working Atom editor configured with the Tidalcycles package can continue to use it. However, the Atom package manager is no longer available to install or update the Tidal package and no further updates to Atom will be available. Tidal users are encouraged to migrate to Pulsar.
If you still have a requirement to use Atom: