Skip to content
BoringStack
GitHub

Cloudflare Email Service

3 min read

Outbound email

The apps/api ships Cloudflare Email Service as the default outbound mail provider. Bundled into Workers Paid with no documented per-message charge, it is usually the cheapest transactional path at non-trivial volume among the providers wired into this template.

Why CloudflareQuickstart

Zero

per-message cost

Pluggable

providers

Beta

release status

Why it’s the default

Section titled “Why it’s the default”
Outbound Email Provider Comparison
Provider
Cost Dynamics
Setup Path
Preconditions
Cloudflare Email
Workers Paid bundle ($5/mo flat; zero per-message cost)
Auto-provisioned SPF/DKIM/DMARC
DNS zone must be managed on Cloudflare
Resend
Free tier, then pay-per-message usage
Manual DNS TXT records validation
None (vendor-neutral API key)
SendGrid
Free tier, then pay-per-message usage
Manual DNS TXT records validation
None (vendor-neutral API key)

Pricing tiers, free-tier limits, and per-message rates all evolve. See Cloudflare · Resend · SendGrid for current numbers.

If you’re already paying for Workers, Cloudflare Email has no per-message cost. BoringStack defaults to it because marginal cost is zero.

Integration

Section titled “Integration”

The API app’s email layer is pluggable: one IEmailService interface, five concrete implementations (Cloudflare, Resend, SendGrid, SMTP, noop). The Cloudflare provider POSTs to an account-scoped endpoint on api.cloudflare.com with a bearer token. Retries, structured logging, and the shared retryWithBackoff wrapper apply equally to all providers; Cloudflare gets the same reliability treatment as Resend. For local template iteration, set EMAIL_PROVIDER=smtp with SMTP_HOST=mailpit and the Mailpit overlay catches everything for inspection.

See Email for the abstraction shape and how dispatch works.

Dev quickstart

Section titled “Dev quickstart”

Dev with no Cloudflare keys → the noop provider logs the rendered payload to stdout instead of sending.

To actually send from dev, inject the following secrets:

Configure Local Development outbound Mail
$ echo 'EMAIL_PROVIDER=cloudflare' >> compose/.env
$ echo 'EMAIL_FROM=noreply@yourdomain.com' >> compose/.env
$ echo 'CLOUDFLARE_ACCOUNT_ID=your_account_id' >> compose/.env
$ echo 'CLOUDFLARE_EMAIL_API_TOKEN=your_scoped_api_token' >> compose/.env

Production setup

Section titled “Production setup”

The step-by-step walkthrough lives in the Cloudflare Email setup runbook: enable Workers Paid, enable Email Service on your domain, capture the account ID, scope a token, smoke-test.

Switching to Resend or SendGrid

Section titled “Switching to Resend or SendGrid”

Change env vars to switch to Resend or SendGrid:

Switch Outbound Mail Provider
$ echo 'EMAIL_PROVIDER=resend' >> compose/.env
$ echo 'RESEND_API_KEY=re_your_resend_api_key' >> compose/.env

Or for SendGrid:

Switch Provider to SendGrid
$ echo 'EMAIL_PROVIDER=sendgrid' >> compose/.env
$ echo 'SENDGRID_API_KEY=SG.your_sendgrid_key' >> compose/.env

The env validator refuses to boot in production if the matching key is missing; switching providers is a one-redeploy operation, not a code change.

Caveats

Section titled “Caveats”
  • Cloudflare Email Service is in beta. Pricing may evolve; daily limits are variable and account-scoped.
  • DNS must be on Cloudflare. Auto-provisioned SPF/DKIM/DMARC are how deliverability works; you can’t skip the step.
  • New accounts can only send to verified addresses until upgraded. The runbook covers the unlock.
Section titled “Related”