Home fit for a mailbox

This is a follow up (part 8) to Sent from my terminal.

Typically, you would build a mailbox to make it easier to communicate to and from your home. Here, I've build this website as a home for my mailbox.

The Minimum viable email service I have been working on now has a new home and a new name to go with it: the basic echo.ls email service (BEES). Since I went through the effort of re-deploying everything, I figured I may as well document the process. Although the instruction set below is specific to my server, it can be easily generalized for any aspiring email-preneurs.

How to deploy an email server

Obtain a server that can serve on ports :25, :110, and :587 (many VPS providers block these ports to prevent spam and domain reputation harm)
Replace hardcoded values (particularly echo.ls in include/config.h)
Clone the repo to your server at /opt/bees/
Build: make clean all
(Optional) Test: make test
Add local users

Write a new line to local_users.txt for each user in the format of [username]:[password].

Generate self trusted cert

openssl req -x509 -newkey rsa:2048 \
  -keyout tls_key.pem \
  -out tls_cert.pem \
  -days 365 \
  -nodes \
  -subj "/CN=mail.echo.ls"

Generate DKIM key

openssl genrsa -out dkim_private.pem 2048
openssl pkey -in dkim_private.pem -pubout -out dkim_public.pem

Generate SPF, DKIM, and DMARC records
```
sh ./scripts/print_mail_dns_records.sh
```
Set SPF, DKIM, and DMARC records for your domain's DNS (from previous step)
Set A and MX record for your domain's DNS
```
mail.echo.ls.		60	IN	A	96.126.120.46
```
and
```
echo.ls.		600	IN	MX	10 mail.echo.ls.
```
Make sure to use your server's public IP address for the A record.
Set a PTR (rDNS) record with your hosting provider

Setup systemd service to run the server

Put this file in /etc/systemd/system/bees.service:

[Unit]
Description=BEES service

# wait for networking
Wants=network-online.target
After=network-online.target

[Service]
Type=simple

# working directory and executable path
WorkingDirectory=/opt/bees
ExecStart=/opt/bees/build/bees

# restarts
Restart=on-failure
RestartSec=5

[Install]
# start on boot
WantedBy=multi-user.target

Reload systemctl: systemctl daemon-reload
Restart BEES: systemctl restart bees
(Optional) Check service status: systemctl status bees
(Optional) Check logs: journalctl -u bees -f

(Optional) Setup mpop as a POP3 client

Write config to ~/.mpoprc:

defaults
tls on
tls_trust_file [local path to tls_cert.pem, required for TLS with self-signed cert]
auth user

account [username]
host mail.echo.ls
port 110
user [username]
password [password]
delivery maildir ~/Maildir
keep on

account default : [username]

(Optional) Setup msmtp as a SMTP client

Write config to ~/.msmtprc:

account [username]
host mail.echo.ls
port 587
from [username]@echo.ls
auth on
user [username]
password [password]
tls on
tls_starttls on
tls_trust_file [local path to tls_cert.perm]

account default : [username]

(Optional) Setup client cron job to autofetch mail

Open cron job editor (crontab -e) then add the following to run mpop once ever five minutes:
```
*/5 * * * * /usr/bin/mpop >/dev/null 2>&1
```

(Optional) Send an email

echo "Subject: Test\n\nHello world" | msmtp alice@echo.ls

Last updated May 16, 2026