To reproduce an issue observed,
git clone https://github.com/inetknght/beast-test && cd beast-test && git submodule update --init --recursive && mkdir build && cd build && cmake ../ -DBeast_BUILD_EXAMPLES=OFF -DBeast_BUILD_TESTS=OFF && make -j$(nproc) ../ && make -j$(nproc)
#[ 50%] Building CXX object src/CMakeFiles/beast_test.dir/main.cpp.o #In file included from beast-test/src/http_async_port.hpp:13:0,
#beast-test/src/http_base.hpp:11:33: fatal error: beast/core/string.hpp: No such file or directory
^
#compilation terminated.
cd ../beast && git remote add inetknght https://github.com/inetknght/Beast && git fetch inetknght && git checkout inetknght/fix-include-directories && cd ../build && make -j$(nproc)