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Synapse App


Matrix is an open network for secure, decentralized communication.

Post installation

Step 1: Select Matrix IDs

Users on matrix has a unique universal id (just like email). These ids are of the form

To give users a "memorable id", this app (also known as home server) is pre-setup to use the second level domain for the domain part of the id (also known as the server_name). For example, if you installed the app at, this app package will set the server_name to This will generate user ids of the form

If you require a different server name, use a File Manager to edit /app/data/configs/homeserver.yaml and restart the app.

Step 2: Delegation

Matrix clients and servers discover Matrix servers using Well-Known URIs. The Well-Known URI is a document served up from the server_name domain (i.e It delegates the handling to the server installation (i.e

If server_name is an app hosted on Cloudron, you can use Cloudron's Well Known URI support to serve up well-known documents.

You can edit well known locations in the Domains view:

Clicking the button will open up a dialog where you can fill up well known locations:

Specify port 443 explicitly

The default matrix server port is 8448. However, the Synapse app on Cloudron uses port 443. For this reason, you must specify the port explicity, like

To verify the delegation setup, try this command from your laptop/PC:

$ curl
{ "m.server": "" }

Requires app on bare domain

In the above example, an app must be installed on the bare domain for Cloudron to be able to respond to well known queries.

Step 3. Federation

Federation setup is automatic. Use the Federation Tester to verify that everything is setup properly. Note you must enter the server_name (like in the form field in the website and NOT the location of your home server (despite what the form says).


To make an existing user an admin, open a Web terminal and run the following command:


No Admin UI

Element has no admin UI (see this and this. The Admin user can use the admin API. For an Admin UI, see the section below.

Admin UI

Synapse does not have a built in admin UI. The Synapse Admin project providers a UI for Synapse configuration.

To use Synapse Admin:

  • Install Surfer
  • Upload the latest tarball from into surfer
  • Extract tarball
  • Login with Synapse credentials. Note that the user you are trying to login with has to be Synapse admin. See [#admin] on how to make a user an admin.

  • You can restrict the login to a specic matrix instance by editing config.json:

  "restrictBaseUrl": "https://homeserver.url"

Public room listing

By default an instance cannot be added for room discovery in other instances. To enable this feature to make public rooms discoverable, add the following to the config file at /app/data/configs/homeserver.yaml:

allow_public_rooms_over_federation: true

Afterwards the matrix synapse app has to be restarted. More details on that option can be found here.


Synapse offers a variety of customizations. To make changes, use a File Manager to edit /app/data/configs/homeserver.yaml and restart the app.

Home page

The index.html can be customized by editing /app/data/index.html. Note that any assets have to be embedded inline.


MSC1772: Matrix Spaces support can be enabled by editing /app/data/configs/homeserver.yaml using the File Manager and adding the following line:

experimental_features: { spaces_enabled: true }

Be sure to restart the app after making the change.