nekbarebone is a cutdown version of nekbone, featuring just the original example2 nekbone test case. nekbarebone is based on version 3.1 of nekbone taken from https://cesar.mcs.anl.gov/content/software/thermal_hydraulics.
All comms specific functionality (i.e., MPI calls) has been moved to the comm source files in the jl sub-directory. Furthermore, the compilation scripts have been altered such that the jl source is built as a static library, which is then linked to the nekbarebone executable.
By default the jl source is compiled to exags.a, however, the nekbarebone executable can instead be made to link to external exags libraries (such as one based on upc for example) by making suitable edits to the ./src/makefile.template file: first, set the IFEXAGSMPI variable to false and then set EXAGSLIBNAME and EXAGSLIBPATH to the name and path of the external exags library.
Instructions on how to build and run the example2 test case can be found in ./test/example2/README.md.