The low level bindings to TVM's C APIs for interacting with the runtime, the cross-language object system, and packed function API.
These will generate bindings to TVM, if you set TVM_HOME variable before building it will instruct the bindings to use your source tree, if not the crate will use tvm-build in order to build a sandboxed version of the library.
This feature is intended to simplify the installation for brand new TVM users by trying to automate the build process as much as possible.