Easiest Groupware to self-host

Last reviewed Oct 11, 2026 · 685 words

For calendars and contacts that sync to your phone, start with Baïkal: one container, the directory's 128 MB estimate, and a web admin page for creating users. The ranking above puts Rallly first, but Rallly is a date-poll tool, not a calendar, and it is the one app on this list with real setup prerequisites. No groupware app has the ≈5-minute badge; every Docker path here is a published image you configure yourself, and Nextcloud Deck has no standalone install at all.

The easy list covers three different jobs

Among the sync servers, Davis is the one beginners overlook. Like Baïkal it wraps sabre/dav with an admin interface, it is MIT-licensed, and the directory puts it at the same 128 MB. It is younger (first released 2020) and smaller, so Baïkal's larger pool of forum answers still makes it the safer first install; the Baïkal vs Davis comparison has the details.

Rallly is easy to use and less easy to install. Login is by emailed magic link, so it needs a Postgres database, a long secret, and SMTP that actually delivers. Get the mail settings wrong and nobody can sign in, which is the usual reason a first Rallly install fails. Set ALLOWED_EMAILS too, or anyone who finds the instance can register.

What "easy" leaves you to do for calendar sync

The reverse proxy is not optional. CalDAV clients send your password with every request, so put TLS in front before the first phone connects. Then forward /.well-known/caldav and /.well-known/carddav to the server's DAV endpoint. Without those redirects, clients that auto-discover find nothing and the server looks broken when it is not.

Persistence and backups are small. Baïkal keeps everything in two folders, config and data, with the data in one SQLite file. Radicale stores plain .ics and .vcf files in a directory. Mount those as volumes and copy them nightly; a whole family's calendars fit in a few megabytes.

Accounts are manual and that is fine. Baïkal and Davis create users from their admin pages, and Radicale reads an htpasswd file. Create one account per person rather than a shared login, so each phone can be revoked on its own.

How much RAM does self-hosted groupware need?

Almost none, for the sync servers. The directory's estimates are 64 MB for Radicale and 128 MB for Baïkal and Davis, which means the reverse proxy in front can easily use more than the server behind it. Rallly's 512 MB plus its Postgres is the heaviest standalone item on the list. Any machine already running Docker has room for all of them.

When to step up to full groupware

Two signals mean you have outgrown a sync server. The first is someone asking to see the calendar in a browser, since none of the easy servers has a calendar view. The second is wanting shared calendars, invitations to outside people, or file sync alongside. That is when Nextcloud with its calendar and contacts apps earns the jump to roughly 1 GB of RAM and a database. Outlook households and larger teams should read the category guide's section on suites before installing anything.

What I'd do

Run Baïkal behind your existing reverse proxy with the well-known redirects in place, create one account per person, and back up the data folder nightly. Add Rallly later on the same host, against a Postgres you already run, the first time a group dinner turns into a 40-message thread. Move to Nextcloud only when someone needs a browser calendar.