calcomposable calendar utilitiesvol. 01 / 2026

cal.

Composable utilities for the calendar pipeline - merge feeds, anonymize details, re-shape time.

§ 01

Aggregate.

Paste a handful of iCal URLs. Receive one combined feed at an immutable address. Subscribe it anywhere.

§ 02

How.

Three steps. No accounts, no setup, no install.

i.
You submit.
Two or more iCal URLs above. A name if you like.
ii.
We mint a feed.
An immutable /ical/<uuid> address that serves the combined calendar.
iii.
Your client subscribes.
Google, Apple, Outlook, Fantastical - every event from every source, in one place.

§ 03

Specimen.

A scrap of what we serve. UID prefixes keep cross-source identity stable.

text/calendarcharset=utf-8

01BEGIN:VCALENDAR
02PRODID:-//cal//EN
03VERSION:2.0
04CALSCALE:GREGORIAN
05X-WR-CALNAME:Team
06BEGIN:VEVENT
07UID:0-9f3e@source.example
08DTSTAMP:20260527T080000Z
09DTSTART:20260601T140000Z
10DTEND:20260601T150000Z
11SUMMARY:Quarterly review
12END:VEVENT
13BEGIN:VEVENT
14UID:1-7c21@source.example
15DTSTAMP:20260527T080000Z
16DTSTART:20260602T090000Z
17DTEND:20260602T093000Z
18SUMMARY:Standup
19END:VEVENT
20END:VCALENDAR

§ 04

Forthcoming.

The aggregator is the first transform. The pipeline keeps growing.

free/busy
Anonymized output.
Emit only busy blocks, details stripped. Share availability without exposing what you are doing.
tripit
Travel night-blocks.
Point cal at a TripIt feed. Configurable busy blocks (e.g. 5pm to 9am) emitted in the local timezone for each trip - so your availability auto-shifts when you travel.
accounts
Authenticated edits.
Sign in to manage, rename, label, and revoke your aggregates.
oauth
Google calendar import.
Pick calendars from a list after OAuth instead of hunting down iCal URLs.
teams
Team availability.
Merge teammates' calendars into a shared free/busy feed for cross-group scheduling.
booking
Availability source.
Use the composed calendar as a feed for cal.com, Calendly, or any iCal-aware booking tool.