NVRHI
NVIDIA Rendering Hardware Interface supplies a common C++ layer for D3D11, D3D12, and Vulkan 1.3 with state tracking, bindings, command lists, multiple queues, ray tracing, and validation.
Why use it
Custom renderers can share most backend code while retrieving native API objects when required, reducing three implementations without adopting a complete game engine.
Where it fits
Find engines, frameworks, code libraries, version control, and production automation.
What to check
Public support is limited to 64-bit Windows and Linux, with no Metal or console backend; automatic barriers still require state knowledge, and optional NVAPI features add separate SDK conditions.