Zabbix - Track, record, alert and visualize performance and availability of IT resources
Unity - The multiplatform game creation tools for everyone.
Datadog - See metrics from all of your apps, tools & services in one place with Datadog's cloud monitoring as a service solution. Try it for free.
Godot Engine - Feature-packed 2D and 3D open source game engine.
Wireshark - Wireshark is a network protocol analyzer for Unix and Windows. It lets you capture and interactively browse the traffic running on a computer network.
Blender - Blender is the open source, cross platform suite of tools for 3D creation.