What are the system requirements for a Threema OnPrem server?

Threema OnPrem requires a Linux server (physical or virtual) with Docker. For smaller deployments of up to 1,000 users, 4 CPU cores, 8 GB RAM, and about 100 GB disk space are sufficient. Larger deployments of up to 100,000 users require 8 more CPU cores, 32 GB of additional RAM, and about 1 TB of disk space. These numbers are highly dependent on the usage intensity.