For team members who prefer to use a third-party messaging client, Slack offers an IRC and XMPP gateway.

Turn on gateway access

To enable team-wide gateway access, expand the Gateways section in the Permissions tab: my.slack.com/admin/settings#gateways.  

Note: The gateway is disabled by default because Slack can make no guarantee about the security of any IRC/XMPP client (including transport encryption or data security). We recommend you enable only the gateways you intend to use and trust only those clients you have evaluated thoroughly. For the highest level of security, we recommend using only Slack's desktop, web, and mobile clients.

Connect to a gateway

Once the gateway is enabled, team members can get connection instructions and their unique gateway password at my.slack.com/account/gateways.

Should your gateway password ever be compromised, please submit a help request so we can generate a new password for your account. Your Team Owner can immediately disconnect all active gateway connections — and block any new ones — by disabling the gateway for the team.

Gateway limitations

While the Slack gateways allow you to use XMPP or IRC to communicate within your Slack team, you will not be able to communicate between Slack teams with other XMPP or IRC servers. 

If you'd like to build an integration to pass messages to and from your Slack team, you can use our HTTP-based API. 

IRC voice messages

When a team member becomes active or inactive in Slack, some IRC clients display a message such as @username voice, or @username de-voice.

To turn on these messages, simply append -voice to your IRC password, then re-launch your client. These messages should then appear.