Ralph

Ralph came out of Allegro, one of the largest e-commerce operations in Europe, and it shows. This is a data-center CMDB built by people who had to track thousands of servers, racks and back-office hardware, not a general-purpose asset app retrofitted for infrastructure.

It is Python and Django under Apache 2.0, free with nothing held back. There is no paid tier and no company selling a hosted version, which cuts both ways: nobody upsells you, and nobody picks up the phone either.

Data-center modeling is where it earns its place. Racks, physical assets, deployment and a transitions system for asset lifecycle, all with a usable API. Solo and small teams: heavier than you need, use Snipe-IT. Large teams running real physical infrastructure: worth a serious look.

The catch is momentum. Development is steady rather than fast and the community is small next to GLPI or NetBox. Confirm the integrations you depend on are still maintained before you commit a hardware estate to it.