Zulip can work with the Slack plugin. Perhaps the documentation could include a little blurb about it.

[xpufx]

Zulip (https://zulip.com) has an incoming webhook API that provides limited Slack style webhook support. I have just tested it and it works.

SLACK_WEBHOOK_URL should be as follows:

https://DOMAINNAME/api/v1/external/slack_incoming?api_key=API_KEY&stream=STREAM_NAME&topic=TOPIC

Zulip has a concept of streams, which are similar to channels, and they require topics for their threading model, hence the stream and topic parameters above. Documentation (url below) states that requests lacking the stream parameter will be handled by sending the message to the creator of the zulip bot as a private message.

The message passed on data like so " </#/alert/13dc8653-4925-4692-a10e-608f42c53e36|13dc8653>" along with the name of the alert etc. I think these can be configured to behave more properly by using a template on the alerta slack plugin side. I did not try this.

Zulip's Slack style incoming webhook documentation. https://zulip.com/integrations/doc/slack_incoming