fastlaneの導入

gemでもbrewでもいけるけど,Gemfile作ってその中に

source "https://rubygems.org"
gem 'fastlane'

https://docs.fastlane.tools/actions/slack/

下記にあるとおり,Incoming WebhookのURLをexportしておく

Create an Incoming WebHook and export this as SLACK_URL. Can send a message to #channel (by default), a direct message to @username or a message to a private group group with success (green) or failure (red) status.

https://docs.fastlane.tools/actions/slack/

https://slack.com/intl/ja-jp/help/articles/115005265063-Slack-%E3%81%A7%E3%81%AE-Incoming-Webhook-%E3%81%AE%E5%88%A9%E7%94%A8

Slackアプリを作成する必要がある

export SLACK_URL=https://hooks.slack.com/services/T****

Done!