The canary schedules a transaction using the ethereum alarm clock to trigger itself every 2 hours. If the transactions do not get executed the canary will die. As long as the canary is up we know that the alarm clock contracts are working properly.
Kovan Canary - 0xde48dcc43196a0347269eb0684da16dcf7f3f788
Ropsten Canary - 0x0e6ed6ab9da0117e15bce9bc35270daeee8257cd
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