# mu4e vs Sup

- mu4e: Email client that runs inside GNU Emacs, built on the mu Maildir indexer and search tool.
- Sup: Curses email client in Ruby built around threads, labels and fast full-text search over local mail.

## Differences

- mu4e is a mail client that runs inside Emacs; Sup is a full-screen terminal client.
- Only mu4e has built-in SMTP.
- Only Sup has built-in mbox.
- On BSD, mu4e runs natively and Sup builds from source.
- On Android, mu4e runs through Termux and Sup is not available.
- mu4e has mouse support; Sup does not.
- mu4e has calendar support; Sup does not.
- mu4e has S/MIME; Sup does not.
- mu4e has OAuth2 sign-in; Sup does not.
- Sup has Vim-style keys; mu4e does not.
- mu4e is written in Emacs Lisp (mu4e), C++ (mu); Sup in Ruby.
- Configuration: mu4e uses Emacs Lisp in init.el, and Sup uses ~/.sup/config.yaml and ~/.sup/sources.yaml, plus Ruby hooks.

## Side by side

| | mu4e | Sup |
| --- | --- | --- |
| Interface | Runs inside Emacs | Full-screen terminal interface |
| Language | Emacs Lisp (mu4e), C++ (mu) | Ruby |
| License | GPL 3.0 or later | GPL 2.0 or later |
| Linux | Native | Native |
| macOS | Native | Native |
| Windows | Through WSL | Through WSL |
| BSD | Native | Build from source |
| Android | Through Termux | Not supported |
| IMAP | Through a separate tool | No |
| POP3 | Through a separate tool | No |
| SMTP | Yes | Through a separate tool |
| JMAP | No | No |
| Maildir | Yes | Yes |
| mbox | No | Yes |
| notmuch | No | No |
| OpenPGP | Yes | Yes |
| S/MIME | via Emacs MML | No |
| OAuth2 sign-in | via script | No |
| Threads | Yes | Yes |
| Search | Xapian full-text index with mu query syntax | Xapian full-text index with a query language |
| HTML mail | built-in, rendered with the Emacs shr library | via the mime-decode hook and an external viewer such as w3m |
| Mouse | Yes | No |
| Multiple accounts | via contexts | Yes |
| Offline use | full; reads a local Maildir synced by mbsync or OfflineIMAP | reads local Maildir or mbox; sync with isync or OfflineIMAP |
| Calendar | replies to invitations with mu4e-icalendar | No |
| Contacts | address completion from indexed mail | tracks recent contacts automatically |
| Vim-style keys | No | Yes |
| Configuration | Emacs Lisp in init.el | ~/.sup/config.yaml and ~/.sup/sources.yaml, plus Ruby hooks |

Pages: [mu4e](https://terminalemail.com/clients/mu4e/index.md), [Sup](https://terminalemail.com/clients/sup/index.md)