mailarch

Archive emails from an IMAP server to a local Maildir.

What it does

mailarch connects to an IMAP server, iterates over all mailboxes, and archives messages older than a configured number of days to a local Maildir directory.

It is designed for exactly one specific use case:

Automatically archive old emails in the background to a local Maildir without any human interaction. The motivation is to keep the information on the remote server to a minimum, while still having access to all emails locally. This can reduce the damage in case of a server compromise, because mail servers typically contain very sensitive information.

Three operating modes are supported:

• copy: Archive to local Maildir, keep messages on the server
• move: Archive to local Maildir, delete messages from the server
• dry-run: Show what would be done without making any changes

What this tool is not about

This is not a generic IMAP client. It cannot be used to do arbitrary operations on the server, and it is not designed for interactive use.

This tool does not support unencrypted IMAP.

Build & Install

./build.sh          # builds release binary
run0 ./install.sh   # installs to /opt/mailarch/

Configuration

The default configuration file is installed at /opt/mailarch/etc/mailarch/mailarch.conf:

Usage

mailarch [--config <path>] <copy|move|dry-run>

Archive emails before Claws-Mail startup

Call the wrapper script claws-mail-archived instead of claws-mail to automatically archive emails before starting Claws-Mail.

systemd

A service and timer unit are provided to run mailarch automatically.

1. Copy the units:

   cp mailarch.service mailarch.timer /etc/systemd/system/

2. Edit mailarch.service to set the correct User/Group and the desired archiving mode (copy or move) in ExecStart.

3. Enable and start the timer:

   systemctl daemon-reload
   systemctl enable --now mailarch.timer

The timer runs once per day (and 5 minutes after boot). Adjust OnUnitActiveSec in mailarch.timer to change the schedule.

License

Copyright 2026 Michael Buesch m@bues.ch with the help of AI coding assistants.

MIT OR Apache-2.0