MailFrom.dev - SMTP sanboxed for devs
I'm excited to share something I've been building: Mailfrom.dev – a sandbox SMTP server for testing emails in staging and dev environments.
If you've ever worked on an app that sends emails, you know the pain...
You want to test password resets, verifications, onboarding flows — but without actually sending emails to real users. I built this so you can drop a sandbox SMTP server right into your staging config and test safely.
Sure, there are other players in the space — but most are either way too expensive or require complex setups. I wanted something affordable and dead simple to use. Just check the pricing — you'll see what I mean.
🛠️ Tech Stack
Backend: Laravel + Horizon, Reverb, Cashier, etc.
Frontend: Vue 3, shadcn, reka
Infra: K3s on Hetzner + AWS S3 & SES
Would love your feedback, feature ideas, or just general thoughts. If you’ve faced similar challenges with email testing, I’d love to hear your story!
Also, we just went live on Product Hunt today — if you want to support the launch, check it out and drop an upvote. Thanks so much 🙏
https://www.producthunt.com/posts/mailfrom-dev-a-sandbox-smtp-for-devs
How is this different from an OSS service like mailhog/mailpit?
Great question!
Tools like Mailhog or Mailpit are great for local testing, but they still require setting up Docker, handling ports, SMTP configs, storage, and sometimes a reverse proxy to make them accessible remotely.
MailFrom dev is different in that:
No setup — just plug in SMTP credentials and start testing
Accessible by teams — no need to expose local ports or share tunnels
Built for collaboration — multiple teams can each have their own SMTP credentials and isolated inboxes out of the box
Built-in automations — you can set up auto-forwarding or manually forward emails to clients or colleagues to easily share your tests
Would love to hear your thoughts if you’ve used Mailhog/Mailpit in a team setting!
Good stuff.
Thank you, every feedback is much appreciated
Passed it on to my team, as soon as they give me some feedback, will post.
Great work, Daniele! Sandbox SMTP is a lifesaver for staging. How are you handling edge cases like bounces or spam-folder simulations? Any plans to plug directly into CI/CD workflows?
Right now, all emails sent to the SMTP server with valid credentials (and within burst limits) are accepted and stored for inspection.
Edge cases like bounces and spam-folder behavior are definitely important, especially for more advanced testing scenarios. I'm already exploring ways to simulate rejections and bounced messages — possibly as configurable options — so developers can test those flows too.
I'm also thinking about adding an API to query delivered messages, especially for use in CI/CD workflows — no ETA yet, but it's something I'll sure do.