Mattermost
Combine filters →Mattermost is a Go chat server with PostgreSQL behind it and WebSockets in front: a persistent process that has to stay up and keep long-lived connections open. That rules out platforms that sleep idle applications and shared hosts without process control; a VPS or a container platform fits. File uploads need a volume or object storage that survives a restart.
1 provider documents support for Mattermost, listed alphabetically. All of them shared hosting. 88 records do not record this field, and cannot appear here either way.