Lately, I’m on a command-line kick. I’m missing the old BBS days. Pine was my primary email client for about a decade. The technology may have moved on, but we can still have some of that old-school feel. In this how-to, I’ll walk you through the process of connecting to Slack with a terminal-based IRC client, irssi.
Note: The administrator of your Slack team will need to enable the IRC gateway before you will be able to use external clients like irssi to connect to Slack.

For OSX:

Install Homebrew

Check to see if Homebrew is installed. Open Terminal and type

which brew

If Homebrew is installed, which will return the path to brew, otherwise, which will return nothing.

If brew is not already installed, visit brew.sh to install it. It’s crazy easy.

Install irssi

Check to see if irssi is already installed. Open Terminal and type

irssi -v

If irssi is installed, it will output the version, otherwise you will get a command not found error.

If irssi is not installed, you can install it using brew.

brew install irssi

Brew will kick out a bunch of output and irssi should be installed, eventually.

Get your configuration information from Slack

Log into Slack and then visit this URL: https://iworkontheinternet.slack.com/account/gateways. Look for your host, username, and password.

Now we will configure irssi to use these settings.

Open Terminal and type

irssi -n your_slack_username

This starts irssi and tells it to use your_slack_username as your default username (or nick as it’s called in IRC). This is required for IRC clients that connect to Slack.

In irssi, type the following:

/server add -auto -ssl your_slack_host 6667 your_slack_password
/quit

This adds the connection information to the irssi configuration file and sets irssi to automatically connect on startup. Now, when you type irssi at the command line, it will automatically connect to Slack. From there, you can use the usual set of IRC client commands to join channels and whatnot. Here are some tutorials on using irssi.

Set Terminal to use Option as Meta

You need to set Terminal to use Option as Meta so that you can use command sequences within Terminal. You really, really need to do this.

  1. Open Terminal.
  2. In the Terminal menu, choose Preferences.
  3. Go to the Profiles tab.
  4. Within Profiles, go to the Keyboard tab.
  5. Check the box labeled Use Option as Meta key
  6. Repeat steps 5 & 6 for each profile you might want to use. Now you can use command sequences like Opt-n to switch between windows in irssi.

For Linux

In Linux, you won’t use brew, you will use the appropriate package manager for your platform. You could also download and compile irssi from source if that’s your jam. The install for irssi will vary by distro but, you’re a Linux user, so you were expecting this. The setup should be the same as above once you have irssi installed.

For Windows

There is a Windows installer for irssi. The setup should be the same as above once you have irssi installed.