For a proper build of 8.9.x, you'll need a large number of external libraries. Generally speaking, you can just keep running the build and installing the obvious packages (usually but not alway
lib<name>-dev). To aid in this process, search build/packaging/new-debian/control for the Build-Depends; some of them are obsolete or apply only when building the manual (latex2html), others only if you're building packages (debhelper).
I use the following script to run cmake. Building with VOMS is broken on Debian, so I didn't even try it for Devuan. Since Devuan is mostly Debian, it was easiest to set the SYSTEM_NAME to Debian and then correct the PLATFORM_STRING and the names of Boost's Python libraries.
Feel free to change _DEBUG, _VERBOSE, and CMAKE_INSTALL_PREFIX.
configure
#!/bin/bash
PWD=`pwd`
cmake \
-D_DEBUG:BOOL=TRUE \
-D_VERBOSE:BOOL=TRUE \
-DWITH_VOMS:BOOL=FALSE \
-DHAVE_EXT_VOMS:BOOL=OFF \
-DSYSTEM_NAME:STRING=Debian \
-DPLATFORM:STRING=x86_64-Devuan-2 \
-DPYTHON_BOOST_LIB:STRING=boost_python27 \
-DPYTHON3_BOOST_LIB:STRING=boost_python35 \
-DCMAKE_INSTALL_PREFIX:PATH=${PWD}/../install \
"$@"