As you may know, Airtable has direct integration with Slack ‘out of the box’. I have just published an article my blog which discusses how to use this to build an absence approval workflow, starting from an employee’s request through to notifying them of approval (or otherwise) - and with a little help from Zapier along the way.
We’ve built an extension that’s ideal fro approval workflows. It allows you to update a certain value an in Airtable record with a click. It provides you with a formula that generates a unique URL (webhook) for each record in your table. When any URL is opened, a specific value will get updated.