So, you want to write a POP3 service? | Hacker News Reader

So, you want to write a POP3 service?

github.com

34 pointsbillpg13 comments

People question why the heck anyone would bother with pop3 in 2023. At Mailsac we find people still use pop3 for testing delivery. It is unsophisticated. Most people use our json to fetch the mail, but sometimes they’ve already got an smtp library open and use the pop feature.

The pop protocol is so simple it’s a fun toy to write, as well. You can do pop against most mail providers. It’s not very secure of course. But has value as a learning tool, too. Knowing how to write text parsers is a useful CS skill.

I download a copy of my mail on my Android phone over POP3 and possibly delete uninteresting messages, for real, on the server. I'm using K9. Then I'll eventually download the remaining messages on my laptop and remove them from the server. A number of Thunderbird filters move messages to their folders and I backup them daily off site. If I stay weeks on vacation, I check my current mail on my phone and that's it. If it's vacation I don't care about old messages. Customers have a copy of them anyway. I've been running like that for at least 12 years, no need for IMAP. Well, maybe if I could access my Thunderbird directory over IMAP, but it's not really important. Running my own IMAP server would be such a small improvement that anything else gets past it in the queue.

I was forced off POP because my email provider stopped supporting it. I never saw anything wrong with it. Goodby ancient, reliable email client, hello thunderbird. And with it, wierdnesses and bugs, and buttock-clenching moments when it tells you it's going to upgrade itself like it or not, and you hope afterwards it hasn't lost anything or changed the UI.

POP3 is still popular for server-to-server bulk transport. I wrote the service to act as a simple listener where anyone can attach their own handlers to provide access to messages. My thinking it would act as a front-end proxy so someone could allow POP3 access to a mailbox by calling through to the REST etc services.

I don’t see why I (or anyone else) should write a POP3 service these days. If you want one-way transmission of messages, you’d be much better off using something like JSONfeed or RSS.

Or if you want a queue, use AMQP.

Or NNTP.

I posted this link on my lunch time, and watched as it disappeared off the "new" page with no points or discussion. I only just checked this morning to see if there was any activity and was surprised to see it had been given points and had some comments. Sorry I missed all the discussion.

A POP3 service seems like a very niche thing to want to write. Especially nowadays, with people reading their e-mail on multiple devices and wanting to keep them in sync.

POP3 still has widespread use as a machine-to-machine bulk email transport. If you want to switch from an old mailbox to gmail, it'll ask you to configure a POP3 client which it will poll and download messages from.

Solution: get rid of all hosted apps and use your own cloud provider (iCloud or Dropbox) to store and sync data. Better yet, there’s a server online 24/7 in your pocket which could serve as such.