Turn on escaping for usernames, channels, and links by flipping the toggle in your slash command's configuration dialog. Always work with user IDs and channel IDs.
Linklater does not currently support parsing the user ID from slash command payloads. This PR adds that functionality.
According to https://api.slack.com/slash-commands#best_practices:
Linklater does not currently support parsing the user ID from slash command payloads. This PR adds that functionality.