`team_join`

Docs: https://api.slack.com/events/team_join (opens in a new tab)

Useful if you want to welcome a team member, or trigger some process when a new Slack user joins the workspace.

MyAppMentionHandler.cs

class TeamJoinHandler : IHandleTeamJoin
{
    public Task<EventHandledResponse> Handle(EventMetaData meta, TeamJoinEvent @evt)
    {
        Console.WriteLine($"{@evt.User.Name} joined the workspace!");
        return Task.FromResult(new EventHandledResponse("OK"));
    }
}

member_joined_channel emoji_changed ( 🆕 v.8.0+)