Nextcloud Mail

Judgement

What it is

Integration

What it does

The Nextcloud mail client app, connecting any IMAP account with a unified inbox, threads, S/MIME and links to Contacts, Calendar and Files.

Adopt it when

Your team works in Nextcloud and wants email in the same interface as files and calendar.

Watch out

Only runs inside Nextcloud, and large mailboxes can be slow because it syncs through PHP.

Ready for

Production-ready

Runs as

Self-hosted server

Built with

PHP, JavaScript, Vue and Horde

How established

Established: started 10 years ago, latest release v1.13.0.

What the license allows

Use inside your business is unrestricted. If you change it and let customers use it over the internet, you must publish your changes.

Judged on 2026-11-03 from the project's README and GitHub data. The license and age lines are worked out directly.

Built from

Follow it down: Nextcloud Mail → V8 → LLVM project → runs on a microchip

How compilers were built, back to punched paper tape

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