Resend + Tevyr

Send transactional email from any Tevyr macro — notify a speaker their session is starting, page a producer when blackout fires, deliver a post-event recap to your hot-list. Resend handles the deliverability; Tevyr fires the request.

What's Resend?

Resend is a transactional email API with first-class DKIM / SPF / DMARC tooling, built for developers who don't want to babysit SMTP. Tevyr's template calls Resend's /emails endpoint with Authorization: Bearer re_… auth. Get an account at resend.com.

#What you can do

Email a speaker before their session starts

Schedule a macro that fires 10 minutes before each session via flow.wait_until → Resend send_email with the speaker's address, the session title, and the green-room link.

Page a producer on critical events

On blackout, on overrun, on Q&A spike — fire a templated email to the on-call producer. SMS-style alerts without an SMS gateway.

Post-event recap to the hot-list

At the end of every event, send a structured recap to your stakeholders: which sessions ran on time, which overran, how many questions came in. One macro, one email blast.

Speaker handoff email between sessions

As one session ends and the next starts, email the incoming speaker a 'you're on next' nudge with their dial-in. Removes a manual stage-manager step.

#Prerequisites

Tevyr Starter plan or above — Free plan ships 0 integration connections
Resend account with billing set up (Resend has a generous free tier — 100 emails/day, 3000/month — but production volume needs paid)
Verified sender domain in Resend (DKIM + SPF + DMARC) — Resend refuses to send from unverified domains in production. The dev sandbox onboarding@resend.dev works for testing
An API key from resend.com/api-keys

#One-time setup

#1. Verify a sender domain in Resend

If you haven't already, follow Resend's domain verification flow:

resend.com/domains → Add Domain
Add the DKIM, SPF, and (optional but recommended) DMARC records to your DNS
Wait for verification (usually under 5 minutes)

Skip this in dev and use onboarding@resend.dev as the From address — it works for testing but emails will land in your test recipient's inbox with a sandbox warning.

#2. Create an API key

resend.com/api-keys → Create API Key
Name it Tevyr, scope: Sending access (or Full access if you also want Tevyr to read domain status)
Copy the key — it starts with re_… and is shown only once

#3. Paste into Tevyr

Settings → Integrations → Add new → Resend
Paste the key, name the connection (e.g. "Resend — production"), click Save
Click Test — Tevyr calls /domains (read-only, lists verified senders). A green toast confirms the key is valid; if the domain list is empty, you'll still get a green toast but you won't be able to send from unverified senders

#Recipes

Drag flow.http_request, pick your Resend connection, pick the Send email action.

#Recipe 1 — Speaker pre-session ping (10-minute warning)

Trigger: flow.wait_until set to {{ctx.session.scheduled_start_time}} - 10 minutes.

Field	Value
From	`Tevyr <no-reply@your-verified-domain.com>`
To	`{{ctx.session.speaker_email}}`
Subject	`Your {{ctx.event.name}} session starts in 10 minutes`
HTML body	`<p>Hi {{ctx.session.speaker_name}}, you're up at {{ctx.session.scheduled_start_time}}. Join here: <a href="{{ctx.event.green_room_url}}">Green Room</a>.</p>`

#Recipe 2 — On-call page on critical overrun

Trigger: lifecycle event on_timer_overrun with threshold ≥ 60 seconds.

Field	Value
From	`Tevyr Alerts <alerts@your-verified-domain.com>`
To	`oncall@your-team.com`
Subject	`[ALERT] {{ctx.session.name}} overrun by {{ctx.timer.overrun_seconds}}s`
Plain-text body	`Session {{ctx.session.name}} just overran by {{ctx.timer.overrun_seconds}} seconds at {{ctx.now.local}}.`

#Recipe 3 — Post-event recap (multiple recipients)

Trigger: lifecycle event on_event_end.

Field	Value
From	`Tevyr Recap <recap@your-verified-domain.com>`
To	`producer@team.com, exec@team.com, comms@team.com` (comma-separate up to 50)
Subject	`{{ctx.event.name}} — post-show recap`
HTML body	(a templated summary with `{{ctx.event.*}}` and `{{steps['<gpt-step>'].output.body.choices[0].message.content}}` if you want AI-generated copy)

#Limits and rules

Warning

Body required: Resend rejects requests with both html and text blank. The macro editor validates this at save time, but if you build a step programmatically, set at least one. Resend prefers html when both are provided.

Limit	Value
Recipients per send (To/CC/BCC combined)	50
Attachments	Up to 40 MB total
Free tier	100 emails/day, 3000/month

#Troubleshooting

#`403 Domain not verified`

You set From to an unverified domain. Either verify the domain in Resend's dashboard, or use onboarding@resend.dev as a temporary sandbox sender (only delivers to addresses you verify in the sandbox).

#`400 Missing required field: html or text`

Both body fields are blank. Set at least one — Resend doesn't accept subject-only emails.

#Email doesn't arrive

Check Resend's dashboard log — every send shows up at resend.com/emails with delivery status
If Resend shows "Delivered" but the inbox is empty, check the recipient's spam folder
If Resend shows "Bounced", the recipient address is invalid

#Sandbox-domain rate limits

onboarding@resend.dev is rate-limited and only delivers to addresses you've pre-verified. For production, always send from your own verified domain.

#Context variables

The From, To, Subject, HTML, and Text fields all support {{ctx.*}} interpolation — Tevyr resolves them at fire time. See the full context-variable reference in the Macros guide. Common ones: {{ctx.event.title}}, {{ctx.session.title}}, {{ctx.session.speaker_name}}, {{ctx.timer.remaining_seconds}}, {{ctx.now.iso}}.

#Triggered by webhook events

Resend can be fired automatically from any webhook event (session.completed, session.upcoming, etc.) — great for post-event recap emails. When creating a webhook, pick Integration mode and select your Resend connection.

Macros — build "speaker on deck" SMS-style flows using Resend + timer warnings
Integrations overview — other tools you can wire alongside Resend
Slack guide — Slack notifications instead of email
Webhooks — for "Tevyr fires when email is delivered" via Resend's outbound webhooks (configured in Resend's dashboard)