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axllent
mailpit
Go2023–2026
axllent / mailpit

mailpit

An email and SMTP testing tool with API for developers

9Distinct people
10Mentions
0Explicit recommenders
10.9KGitHub stars
REPOSITORY AT A GLANCE

What to know before exploring

What it is

An email and SMTP testing tool with API for developers

GitHub

Where it is used

No documented product use has been verified yet.

What people are saying

No recommendation phrase was found in the indexed comments.

No classified warning is attached to this page. Read the discussions before treating silence as approval.

Also in these discussions

No other repository is repeatedly linked in the same discussions.

This week on Hacker News

Nov 7–Nov 14 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/14/2026, 3:56:07 PM UTC.

No direct repository links were found in the indexed HN discussions over the past seven days. Older discussions are available below.

Mentions over time

HN mentions by year10 dated mentions

Observed mentions: 2023-03-05 13:52:07 UTC to 2026-06-09 20:42:11 UTC.

0123452023-01-01 00:00:00 UTC to 2024-01-01 00:00:00 UTC (exclusive): 5 mentions; 1 submissions, 4 comments20232024-01-01 00:00:00 UTC to 2025-01-01 00:00:00 UTC (exclusive): 4 mentions; 0 submissions, 4 comments20242025-01-01 00:00:00 UTC to 2026-01-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2026-01-01 00:00:00 UTC to 2027-01-01 00:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 comments. Incomplete calendar period.2026*

* An incomplete calendar period is marked with an outlined bar. Its count is not directly comparable with a full period.

Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.

View mention counts and date ranges
UTC ranges include their start and exclude their end. Select a period to filter the source evidence.
PeriodStart (UTC)End (exclusive, UTC)MentionsSubmissionsComments
20232023-01-01 00:00:00 UTC2024-01-01 00:00:00 UTC514
20242024-01-01 00:00:00 UTC2025-01-01 00:00:00 UTC404
20252025-01-01 00:00:00 UTC2026-01-01 00:00:00 UTC000
2026 (partial)2026-01-01 00:00:00 UTC2027-01-01 00:00:00 UTC101

What Hacker News says

10 sources
It really only likely matters if you're one of those who is tempted to let it run on `0.0.0.0` instead of loopback only. Assuming you're not, there's certainly no urgency to migrate. But keep it in the back of your mind that it's unmaintained, and if things go weirdly wrong during an OS or ruby upgrade, remember that you will need to fix it or pick up something else that's kind of similar. If you're not already using it, it might be a good idea to pick up something else. I like [mailpit](https://github.com/axllent/mailpit) because it's a single static binary and because it has a nice api I can use during testing to see if a message made it out of the system I'm testing. But none of that argues for switching away from a thing that's working for you.
In MailCatcher runs a super simple SMTP server
I agree with pwg that postfix is fairly straight forward but to answer your question there are debugging programs that capture email such as mailpit [1] but I don't know if you would consider that to be easier. I have not tried it out yet as I have always used smtp-sink for debugging part of postfix tools. Mailpit has a nifty web UI and claims to process 70 to 100 emails per second. The reason I suggested Postfix is due to the nature of it being on many internet facing servers and being battle-hardened over the decades and having started off very secure. Anything else should probably be confined behind bubblewrap and AppArmor or SELinux. Regardless of what tool you end up using consider adding firewall rules to explicitly block outbound SMTP in the event someone finds a way to relay through whatever tool you end up using as a bumper-gu
Read the rest
ard against configuration mistakes and bugs. [1] - https://github.com/axllent/mailpit
In Ask HN: What is cheapest way to just receive (not send) email to a domain I own?
My work machine is prohibited from connecting to port 25 outside of the accepted work systems. When on VPN, I can't even connect to port 25 within the local networks. docker run -d --name=mailpit --restart unless-stopped -p 8025:8025 -p 1025:1025 axllent/mailpit I can connect to port 1025 just fine. --- This test data isn't something that should be leaving the local network either. Can you run mailtrap.io on your local machine or in your data center? --- Oops, I accidentally set it to send all the emails. How much does it cost to handle 500 email in the next few minutes? Mailpit is free. --- That 500 test email that were sent to mailpit, they're correct and should be sent out to the testers. https://github.com/axllent/mailpit/wiki/SMTP-relay What is the cost to forward 500 emails this week? And again next week? --- Mailpit (and i
Read the rest
ts predecessor Mailhog) were not difficult at all to spin up and test. Any developer with docker running on their machine can do local testing without any issues. Data never leaves the machine or intranet - this makes security types sweat less.
In Mailpit – An email and SMTP testing tool with API

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