Stacks / Email
Mailpit
SMTP you catch. Mailpit is MIT — Mailtrap without the hosted inbox seat.
The problem
Mailtrap is a hosted fake SMTP inbox for staging mail. You wanted to catch messages on a box you run. Mailpit is MIT (axllent/mailpit; last push 22 Oct 2026) — an SMTP server plus a web UI and an API. This is not Mailtrap's every QA, email-API, or deliverability SKU. Production send stays on /replace/postmark (Plunk / Resend). A mailbox you live in stays on /replace/gmail. MailHog is unmaintained — not the published path.
Replaces
Mailtrap
Estimated SaaS saved
$1,200
per year, small team, before lock-in
Start on RailwayPlunk if this is production send, not a catch inbox
Placeholder: Mailpit (official image) plus a volume if you persist messages. Bind HTTP to 0.0.0.0:$PORT. SMTP on the documented port. No one-click template in this repo yet — Start on Railway. Production send stays on /stacks/plunk-newsletter.
The stack
- Mailpit
MIT SMTP catcher and web UI — the published Mailtrap path
Cost table
| You stop paying | Typical / year | Self-host instead |
|---|---|---|
| Mailtrap / hosted test inbox (small team) | $1,200 | Mailpit |
Agent setup prompt
Replace Mailtrap with Mailpit (https://mailpit.axllent.org). - Official image. Point the app's SMTP at Mailpit. Open the UI and confirm one message. Do not claim Mailtrap QA suites or production deliverability. - MailHog is unmaintained — do not publish it as the path. Production send stays on /stacks/plunk-newsletter. - Write AGENT_PROMPT.md.
Also as markdown: /stacks/mailpit-smtp.md
FAQ
- Is this Postmark?
- No. Production transactional send stays on /replace/postmark. This page is a staging catch inbox.
- Why not MailHog?
- MailHog is unmaintained. Mailpit is the MIT catcher that still gets commits.
- Are these free?
- Mailpit is MIT. You pay hosting. Template users never pay c17.