# Z-Push licensing notes (AGPLv3)

This image bundles [Z-Push](https://github.com/EGroupware/z-push) (EGroupware
fork), licensed under the **GNU Affero General Public License v3**.

## Why this doesn't affect dezky's own code

Z-Push runs as an **isolated network service**. dezky components talk to it
only over network protocols (HTTPS for EAS clients; Z-Push itself talks to
Stalwart over IMAP/CalDAV/CardDAV). Nothing links against Z-Push code, so the
AGPL's copyleft does not extend to the portal, platform-api, or any other
dezky service.

## What the AGPL obliges us to do

Because users interact with Z-Push over a network, AGPL §13 requires that we
offer them the **corresponding source of the exact version we run, including
our modifications**. Our modifications are:

- the pinned upstream version (see `ZPUSH_VERSION` in the `Dockerfile` and
  `/usr/share/z-push/DEZKY_PINNED_VERSION` in the image)
- the replaced config files in `config/`
- the autodiscover dispatcher `autodiscover-router.php`
- two sed-patched values in the main `config.php` (TIMEZONE,
  BACKEND_PROVIDER — see `Dockerfile`)
- a one-line PHP 8 fix in
  `backend/ipcsharedmemory/ipcsharedmemoryprovider.php` (a debug sprintf of
  SysV handles that are objects, not resources, since PHP 8.0 — see
  `Dockerfile`)

Everything lives self-contained in this directory. **Compliance action:** the
client-setup/help page that documents Exchange account setup must link to
(a) the upstream tag on GitHub and (b) this directory's contents (or a
published copy of them). Keep that link in step with `ZPUSH_VERSION` bumps.

Z-Push's own license text ships in the image at `/usr/share/z-push` (see the
upstream `LICENSE` file in the cloned repository root).