General Slack Accessibility : https://slack.com/accessibility
Use Slack with a screen reader: https://slack.com/help/articles/360000411963-Use-Slack-with-a-screen-reader
Navigate Slack with your keyboard: https://slack.com/help/articles/115003340723-Navigate-Slack-with-your-keyboard
Feel free to reach out to our accessibility chair Jim Hahn (jimhahn@upenn.edu) with any questions or suggestions.