Microsoft has open-sourced Casablanca (the C++ REST SDK) on GitHub.
To make it easy to use on Fedora, I packaged and published RPMs on Fedora COPR: COPR: ritz/cpprestsdk
To enable the repository and install:
sudo dnf copr enable ritz/cpprestsdk
sudo dnf install cpprest-devel
Happy compiling with -lcpprest!