stapel-calendar

Calendar and scheduling: events with participants and RSVP, RFC 5545 recurring series (virtual expansion, on-demand materialization, per-instant cancellation and reschedule), availability windows with free/busy and bookable slot computation, ICS export, and event-driven reminders.

Part of the Stapel framework — composable Django apps that deploy as a monolith or as microservices without changing module code.

Install

pip install stapel-calendar

At a glance

Fact	Value
Version	`0.4.2`
Python	`>=3.11` (3.11, 3.12, 3.13, 3.14)
HTTP operations	10
Config axes	1
Usage surface	31
Extension points	5
Error codes	48
Fleet dependencies	`stapel-auth` (optional) · `stapel-core` · `stapel-notifications` (optional)

Documentation

OpenAPI · capabilities.json · llms.txt (for agents)

What this is

A generic calendar core — Event / Participant / RSVP, an RFC 5545 recurrence engine (RRULE via python-dateutil, virtual expansion + on-demand materialization), availability (working windows, free/busy, slots) and ICS export. Two flavors of one domain — meetings and bookings — share this core; everything app-specific lives behind seams.

Quick start

INSTALLED_APPS = [
    # ...
    "stapel_calendar",
]

# urls.py
path("calendar/", include("stapel_calendar.urls"))

Concepts

Event — a scheduled thing (meeting/booking/appointment) with tz-aware start/end, an owner and an opaque scope_key. No FK to any host concept (org, room) — scoping and resources are seams.
Recurrence — the series master stores a canonical RRULE. Occurrences are virtual until they gain their own state (an RSVP or a resource), at which point they are materialized (persisted) on demand.
Availability — recurring working windows minus busy events give open booking slots.

from stapel_calendar import services

series = services.create_event(
    owner=user, title="Standup",
    start=start, end=end,
    recurrence_type="weekdays",            # -> FREQ=DAILY;BYDAY=MO,TU,WE,TH,FR
)
occurrences = services.expand_event(series, range_start, range_end)  # virtual
services.materialize(series, occurrence_start)  # persist one + emit hook
busy = services.free_busy(user, range_start, range_end)
slots = services.compute_slots(user, range_start, range_end, slot_minutes=30)

Settings

All configuration lives in the STAPEL_CALENDAR namespace (dict setting, flat setting, or env var — resolved lazily):

Key	Default	Meaning
`SCOPE_PROVIDER`	`…scope.DefaultScopeProvider`	Resolve/filter the opaque `scope_key`
`REMINDER_POLICY`	`…reminders.DefaultReminderPolicy`	When/what to remind
`PRESETS`	`{}`	Custom recurrence presets (merged over built-ins)
`REMINDER_OFFSETS`	`[10]`	Minutes before start to remind
`REMINDER_SCAN_WINDOW_SECONDS`	`60`	Reminder cron granularity
`DEFAULT_EXPANSION_HORIZON_DAYS`	`90`	Default range end
`MAX_EXPANSION_OCCURRENCES`	`1000`	Expansion safety cap
`DEFAULT_SLOT_MINUTES`	`30`	Default slot length

comm surface

Kind	Name	Contract
Emit	`calendar.occurrence.materialized`	An occurrence was persisted — subscribe to attach a resource
Emit	`calendar.event.reminder_due`	A reminder is due — deliver it
Function	`calendar.free_busy`	`{user_id, start, end, scope_key?}` -> `{busy: [...]}`

Extension points

See MODULE.md — the agent-facing map of every fork-free seam (the resource hook, reminder policy, scope provider, recurrence presets, serializer seams, settings).

Development

pip install -e . && pip install pytest pytest-django ruff
./setup-hooks.sh
pytest tests/

License

MIT — see LICENSE.

_{This page is assembled by stapel-readme from docs/readme.md plus the contract artifacts in docs/. Edit the prose in docs/readme.md; the badges, facts and links above and below it are generated — do not hand-edit README.md.}

Development Status
- 4 - Beta
Framework
- Django
Intended Audience
- Developers
License
- OSI Approved :: MIT License
Operating System
- OS Independent
Programming Language
Typing
- Typed

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

stapel_calendar-0.4.2.tar.gz (85.7 kB view details)

Uploaded Aug 15, 2026 Source

Built Distribution

If you're not sure about the file name format, learn more about wheel file names.

The dropdown lists show the available interpreters, ABIs, and platforms. Enable javascript to be able to filter the list of wheel files.

stapel_calendar-0.4.2-py3-none-any.whl (74.7 kB view details)

Uploaded Aug 15, 2026 Python 3

File details

Details for the file stapel_calendar-0.4.2.tar.gz.

File metadata

Download URL: stapel_calendar-0.4.2.tar.gz
Upload date: Aug 15, 2026
Size: 85.7 kB
Tags: Source
Uploaded using Trusted Publishing? Yes
Uploaded via: twine/7.0.0 CPython/3.13.14

File hashes

Hashes for stapel_calendar-0.4.2.tar.gz
Algorithm	Hash digest
SHA256	`e24597eb2bb25e3c4d0c7f22b05348f1e94caee778447bb399b20ed4a6dbeec5`
MD5	`27f1829f837655fa82c0dbbf017fcaa0`
BLAKE2b-256	`a722eb8a2ad07a4fa2a23771ae9fbf5b022e18b39ffaf9283e46cc935df35260`

See more details on using hashes here.

Provenance

The following attestation bundles were made for stapel_calendar-0.4.2.tar.gz:

Publisher: publish.yml on usestapel/stapel-calendar

Attestations: Values shown here reflect the state when the release was signed and may no longer be current.

Statement:
- Statement type: https://in-toto.io/Statement/v1
- Predicate type: https://docs.pypi.org/attestations/publish/v1
- Subject name: stapel_calendar-0.4.2.tar.gz
- Subject digest: e24597eb2bb25e3c4d0c7f22b05348f1e94caee778447bb399b20ed4a6dbeec5
- Sigstore transparency entry: 2477686952
- Sigstore integration time: Aug 15, 2026
Source repository:
- Permalink: usestapel/stapel-calendar@3740693bba2917f15de0b5956dd66763d48f0afe
- Branch / Tag: refs/tags/v0.4.2
- Owner: https://github.com/usestapel
- Access: public
Publication detail:
- Token Issuer: https://token.actions.githubusercontent.com
- Runner Environment: github-hosted
- Publication workflow: publish.yml@3740693bba2917f15de0b5956dd66763d48f0afe
- Trigger Event: push