idled vs. notifyd ?

[Patrick Goetz]

On 12/12/2014 04:04 AM, Bron Gondwana wrote:
> http://blog.fastmail.com/2014/12/02/dec-3-push-it-real-good/
>

 From this blog post:
"We’ll talk about notifyd first, because it’s the simpler of the two. 
The two main styles of events it handles are calendar email 
notifications and Sieve (filter/rule) notifications.

Calendar email notifications are what you get when you say, for example, 
'10 minutes before this event, send me an email'. All the information 
that is needed to generate an email is placed into the event that comes 
from Cyrus, including the name of the event, the start and end time, the 
attendees, location, and so on. notifyd constructs an email and sends it 
to the recipient. It does database work to look up the recipient’s 
language settings to try and localise the email it sends. Here we see 
database and email work, and so it goes on the slow path."


What calendar is it that is using notifyd like this?