Question 1

How often does YourCals poll iCal feeds?

Accepted Answer

Polling frequencies depend on your plan, ranging from real-time dynamic intervals to scheduled background syncs.

Question 2

What happens when a calendar event changes?

Accepted Answer

YourCals detects the diff/delta in the iCal feed and instantly triggers an HTTP POST webhook payload to your endpoint.

Question 3

We already poll feeds in our own workers. Why move?

Accepted Answer

Because most of that traffic buys you nothing: an unchanged feed still costs a full round trip and a parse to learn that nothing happened. YourCals keeps the validator state per feed, so an unchanged calendar stops at a 304 and only real changes reach your API. The crons, the retry queues and the parser go with it.

Question 4

What has to change on our side?

Accepted Answer

An endpoint that accepts a POST and verifies our signature. Everything else is ours: registering feeds through the API or the dashboard, polling them, validating the response, diffing it and delivering the change set. The calendar providers never hear from you.

Question 5

How does billing work?

Accepted Answer

Monthly or annually, per plan, in euros. The annual price is charged once for twelve months and saves 15% on Starter and 16% on Growth. Webhook deliveries are never metered, so a calendar that moves every hour costs the same as one that never moves.

Question 6

What counts as a feed?

Accepted Answer

One iCal or webcal URL, wherever it comes from. If several of your users connect the same public calendar, YourCals fetches it once and notifies each of them, so a popular calendar is not polled once per subscriber.

Question 7

Do you store calendar data?

Accepted Answer

By default YourCals stores only a hash of each feed. Notify-only mode sends the event name and the feed URL, and nothing from inside the events, which keeps the default plan's data scope minimal.

Question 8

What happens when a provider goes down?

Accepted Answer

Nothing is sent. A failed, empty or non-calendar response is treated as missing data rather than as an empty calendar, the feed is paused, and we try again on schedule.

Question 9

How are webhooks authenticated?

Accepted Answer

Each delivery is signed with HMAC-SHA256 over the timestamp and the raw body, and sent in the X-Hub-Signature-256 header as t=,v1=. Your receiver recomputes the digest and rejects timestamps older than five minutes, which is what closes the replay window.

Question 10

Can I sign in with Google or GitHub?

Accepted Answer

Yes. Email sign-up works too, with a one-time code sent to your phone or email to verify the account.

Notes from the polling queue

Most iCal polling is wasted work

When a calendar cannot be read at all