First, a disclosure: I'm a fan. Tymeslot is the scheduler behind my own booking link, tymeslot.app/kraakman, so every sales call at AhaSend already starts with it. You share one link, people pick a slot, and it stays in sync with your calendar.
It comes in two flavours: a hosted SaaS at tymeslot.app, where you sign up and start booking in a couple of minutes, and the same product as source you run yourself with Docker. The code is public under AGPLv3, the booking pages load no ad pixels or tracking scripts, and it's written in Elixir, which we have a soft spot for.
On the hosted version, email is handled for you and there's nothing to configure. This post is about the other flavour.
Anything that books meetings lives or dies on email: the confirmation with the .ics attachment, the reminder, the mail that tells you someone cancelled. Self-hosted installs have to bring their own provider for that, and since v1.6.0 Tymeslot supports AhaSend natively. It calls our HTTP API directly, so there's no SMTP relay in the middle to configure or debug.
Setting up is easy
- Sign up for AhaSend and verify your sending domain.
- Create an API key with send permission. You'll also need the account UUID it belongs to, because Tymeslot wants both.
- Set
EMAIL_ADAPTER=ahasend,AHASEND_API_KEY=<your-key>andAHASEND_ACCOUNT_ID=<account-uuid>. On a fresh install, setEMAIL_FROM_ADDRESSandEMAIL_FROM_NAMEtoo, since Tymeslot refuses to boot without them. - Restart, then check the logs. Tymeslot tests the credentials against our API on startup and either logs that they validated or prints an error naming the variables to fix. Worth a look, because the other way to find out is a customer telling you their confirmation never showed up.
- Book yourself a test meeting.
That's the whole migration. Confirmations, reminders and cancellations now go out through AhaSend, and you can watch each one land in the dashboard.
What it costs
Tymeslot itself is free to self-host, the full product under AGPLv3 with no paywalled features. On our side, the free plan is 1,000 emails a month with no card, and a personal instance or a small team won't come close to that. So the whole stack, scheduler plus email, can run at exactly zero.
If you outgrow it, our paid plans start at €9 a month, which is also, pleasingly, what Tymeslot's own Cloud Pro tier costs. And if you'd rather not run servers at all, their hosted version starts free at tymeslot.app, with email already handled.
If you'd rather use something else
We won't pretend we're the only option. Tymeslot also ships native support for Postmark, SendGrid and Mailgun, and anything with an SMTP relay works via EMAIL_ADAPTER=smtp. Mailgun will even sell you an EU region.
What none of those give you is a chain that is European all the way up. Tymeslot is an Estonian company and we're a Dutch one, so a booking never has to touch an American vendor on its way to your client. An EU region bought from an American provider still comes with an American parent company, and the US CLOUD Act reaches the parent regardless of where the servers sit.
The last hop
If you self-host to keep hold of your data, the last hop deserves the same standard as the first. You picked the server, you picked the scheduler, you can read the code that writes the email. The provider that carries it out of your building shouldn't be the one part of the chain you stopped asking questions about.