Calendar for the week(yep, even for hour)

Hello guys !

I'm admin and I want to schedule some server tasks via web. Therefore I
need good calendar which supports hours and days of week.

For example I want to set task which will work every Sunday at 5:00 or
Mondey 18:35 and so on. I see many, tons of month calendars, but I need
only weekly calendar, with good API because I use activerecord from ruby
for access to database and perform given tasks.

I do not want google like calendars for this lol

Thanks !