aerc vs mu4e
aerc: Terminal email client written in Go with IMAP, JMAP, Maildir and notmuch backends and an embedded terminal for editing.
mu4e: Email client that runs inside GNU Emacs, built on the mu Maildir indexer and search tool.
Differences
- aerc is a full-screen terminal client; mu4e is a mail client that runs inside Emacs.
- Only aerc has built-in IMAP, JMAP, mbox and notmuch.
- mu4e has S/MIME; aerc does not.
- aerc has Vim-style keys; mu4e does not.
- aerc is written in Go; mu4e in Emacs Lisp (mu4e), C++ (mu).
- Configuration: aerc uses INI-style files: accounts.conf, aerc.conf, binds.conf, and mu4e uses Emacs Lisp in init.el.
Side by side
| aerc | mu4e | |
|---|---|---|
| Interface | Full-screen terminal interface | Runs inside Emacs |
| Language | Go | Emacs Lisp (mu4e), C++ (mu) |
| License | MIT | GPL 3.0 or later |
| Latest version | 0.22.0 | 1.14.3 |
| Linux | Native | Native |
| macOS | Native | Native |
| Windows | Through WSL | Through WSL |
| BSD | Native | Native |
| Android | Through Termux | Through Termux |
| IMAP | Yes | Through a separate tool |
| POP3 | No | Through a separate tool |
| SMTP | Yes | Yes |
| JMAP | Yes | No |
| Maildir | Yes | Yes |
| mbox | Yes | No |
| notmuch | Yes | No |
| OpenPGP | Yes | Yes |
| S/MIME | No | via Emacs MML |
| OAuth2 sign-in | Yes | via script |
| Threads | Yes | Yes |
| Search | built-in; server-side for IMAP and JMAP; notmuch queries | Xapian full-text index with mu query syntax |
| HTML mail | via filters, w3m by default | built-in, rendered with the Emacs shr library |
| Mouse | Yes | Yes |
| Multiple accounts | Yes | via contexts |
| Offline use | with mbsync or OfflineIMAP through the Maildir backend; IMAP header cache | full; reads a local Maildir synced by mbsync or OfflineIMAP |
| Calendar | Yes | replies to invitations with mu4e-icalendar |
| Contacts | via address-book-cmd, e.g. khard or the bundled carddav-query | address completion from indexed mail |
| Vim-style keys | Yes | No |
| Configuration | INI-style files: accounts.conf, aerc.conf, binds.conf | Emacs Lisp in init.el |
Which to choose
Choose aerc for
- Embedded terminal runs the editor and other commands inside aerc
- Built-in commands for applying and reviewing git patch series
- Supports JMAP and notmuch as well as IMAP and Maildir
Watch out for
- No POP3 or S/MIME support
- mbox files open read-only
- No native Windows build
Choose mu4e for
- Full-text search over all local mail through mu's Xapian index.
- Works offline, since all mail lives in a local Maildir.
- Uses Emacs message mode, so PGP/MIME, S/MIME and Org mode links are available.
Watch out for
- No built-in IMAP; needs mbsync or a similar sync tool, so setup spans several config files.
- Requires Emacs and some Emacs Lisp to configure.
- No native Windows build, and Arch packages it only in the AUR.
Questions
What is the difference between aerc and mu4e?
aerc is a full-screen terminal client; mu4e is a mail client that runs inside Emacs. Only aerc has built-in IMAP, JMAP, mbox and notmuch. mu4e has S/MIME; aerc does not.
Which runs on Windows, aerc or mu4e?
On Windows, aerc runs through WSL. On Windows, mu4e runs through WSL.
See also: aerc alternatives, mu4e alternatives.