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Calendar subscriptions

Subscribe to a private, revocable calendar of a Project’s Sprint dates and Work Item due dates from Google Calendar, Apple Calendar, Outlook, or any client that speaks RFC 5545 iCalendar over HTTPS.

The feed is a user-specific credentialed read surface, never a public Project-sharing link: one feed exists per person per Project, and the subscription URL is a bearer secret.

Create a subscription

  1. Open the Project’s Settings → Calendars section (available to anyone who can read the Project).
  2. Choose the event sources to include — Sprints and Work Items with due dates. Both are on by default; at least one must stay enabled.
  3. Select Create subscription. Hamstik shows the subscription URL once. Copy it immediately and paste it into your calendar client as a “Subscribe from URL” calendar. Hamstik stores only a hash, so nobody — including Hamstik support — can show the URL again. If you lose it, use Rotate URL to mint a replacement.

The subscription URL is a bearer credential

  • Anyone who has the URL can read this one feed without signing in. It cannot create a session, cannot call any other Hamstik API, and exposes only this Project’s window of Sprint and due-date events.
  • Serve and share it only over HTTPS (https://hamstik.com/api/calendar/<secret>.ics). Responses are private and uncacheable by intermediaries, and referrer data is suppressed. Never paste the URL into analytics tools, chat messages, or share previews.
  • External copies cannot be recalled. Calendar clients download and cache events on their own schedule (often every few hours). Revoking or rotating the URL stops future downloads but cannot remove copies a client has already stored.

What the feed contains

  • Work Item due dates as point-in-time UTC events at the stored due timestamp, named KEY Title. No descriptions, comments, attachments, or people are ever included.
  • Sprints as all-day ranges from start date through end date inclusive, named PROJECT-KEY: Sprint name.
  • A window covering the last 90 days through the next 365 days relative to UTC today. Items outside the window, archived or deleted Work Items, and Sprints without valid dates are omitted on the next refresh.
  • Stable event identities: when a Work Item or Sprint changes, your calendar client updates the existing event instead of creating a duplicate.
  • A complete feed is capped at 10,000 events. If a Project would exceed the cap, the client receives an explicit error instead of a silently truncated calendar; narrow the feed by disabling a source and retry.

Rotate, revoke, and access changes

  • Rotate URL invalidates the previous subscription URL immediately and shows the replacement once. Update every calendar app that used the old URL.
  • Revoke feed invalidates the URL immediately. A revoked feed never blocks creating a replacement later.
  • Revocation also happens automatically: when you lose access to the Project, leave the Organization, your account is disabled, the Organization is suspended, or the Project is archived, the URL stops working on the next fetch and returns an empty error — never a redirect or stale content.
  • Feed management is available to Project readers in the Project settings, and through the Public API with the calendar:read / calendar:write scopes on your own feeds only.

Client interoperability

The feed is standard RFC 5545 iCalendar served over HTTPS with text/calendar content. Add it as a “From URL” / “Subscribe” calendar in your client. Each client refreshes on its own schedule; forced refreshes vary by product. If a client rejects the URL, confirm it accepts HTTPS calendar URLs without extra authentication.