diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7ddec8b..c4f00c7 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,10 +1,9 @@
-cmake_minimum_required(VERSION 3.18)
+cmake_minimum_required(VERSION 3.21)
 
 set(project remhos)
 project(${project} LANGUAGES CXX)
 set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
-set(CMAKE_CXX_COMPILER_LAUNCHER ccache)
 set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 
 # CXX flags *******************************************************************
@@ -18,21 +17,35 @@ set(CMAKE_CXX_FLAGS_RELWITHDEBINFO "-O2" CACHE STRING "" FORCE)
 
 # Verbosity options ***********************************************************
 set(CMAKE_VERBOSE_MAKEFILE OFF CACHE BOOL "" FORCE)
-# set(CUDA_VERBOSE_BUILD OFF CACHE BOOL "" FORCE)
-
-# Include paths ***************************************************************
-include_directories(${CMAKE_CURRENT_SOURCE_DIR})
-include_directories(${CMAKE_CURRENT_SOURCE_DIR}/../mfem)
-if (${CMAKE_SYSTEM_NAME} MATCHES "Linux")
-include_directories(/usr/include/hypre /usr/include)
-elseif(${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
-include_directories(/opt/homebrew/opt/fmt/include
-                    /opt/homebrew/opt/openmpi/include
-                    /opt/homebrew/opt/metis/include
-                    /opt/homebrew/opt/hypre/include)
-add_compile_definitions(MFEM_USE_CMAKE_TESTS)
-else()
-    message(FATAL_ERROR "Unsupported system")
+
+# Dependencies ****************************************************************
+find_package(HYPRE REQUIRED)
+find_package(MFEM REQUIRED)
+find_package(MPI REQUIRED)
+
+option(REMHOS_USE_CALIPER "Use Caliper" OFF)
+if (REMHOS_USE_CALIPER)
+    find_package(caliper REQUIRED)
+    find_package(adiak REQUIRED)
+endif()
+
+# HIP support *****************************************************************
+# Read MFEM_USE_HIP from MFEMConfig or from the cache (passed via -DMFEM_USE_HIP=ON)
+if (NOT DEFINED MFEM_USE_HIP)
+    set(MFEM_USE_HIP OFF)
+endif()
+
+if (MFEM_USE_HIP)
+    if(NOT DEFINED CMAKE_HIP_ARCHITECTURES)
+        set(CMAKE_HIP_ARCHITECTURES gfx942)
+    endif()
+    enable_language(HIP)
+    set(CMAKE_HIP_STANDARD ${CMAKE_CXX_STANDARD} CACHE STRING
+        "HIP standard to use.")
+    set(CMAKE_HIP_STANDARD_REQUIRED ON CACHE BOOL
+        "Force the use of the chosen HIP standard.")
+    set(CMAKE_HIP_EXTENSIONS OFF CACHE BOOL "Enable HIP standard extensions.")
+    message(STATUS "Using HIP architecture: ${CMAKE_HIP_ARCHITECTURES}")
 endif()
 
 # Copy mesh files *************************************************************
@@ -46,40 +59,73 @@ add_custom_command(OUTPUT data_is_copied
 add_custom_target(copy_mesh_files DEPENDS data_is_copied)
 
 # Library source files ********************************************************
-add_library(Remhos STATIC remhos.cpp remhos_fct.cpp 
-                          remhos_ho.cpp remhos_lo.cpp 
-                          remhos_mono.cpp remhos_sync.cpp 
-                          remhos_tools.cpp)
+set(LIB_SOURCES
+    remhos.cpp
+    remhos_fct.cpp
+    remhos_ho.cpp
+    remhos_lo.cpp
+    remhos_mono.cpp
+    remhos_solvers.cpp
+    remhos_sync.cpp
+    remhos_tools.cpp
+)
+
+if (MFEM_USE_HIP)
+    set_source_files_properties(${LIB_SOURCES} PROPERTIES LANGUAGE HIP)
+endif()
+
+add_library(Remhos STATIC ${LIB_SOURCES})
+
+target_compile_definitions(Remhos PUBLIC MFEM_USE_CMAKE_TESTS)
 
-# Testing options *************************************************************
+target_include_directories(Remhos PUBLIC
+    ${CMAKE_CURRENT_SOURCE_DIR}
+    ${MFEM_INCLUDE_DIRS}
+    ${MFEM_INCLUDE_DIRS}/mfem
+)
+
+target_link_libraries(Remhos
+    PUBLIC mfem
+    PUBLIC MPI::MPI_CXX
+    PUBLIC HYPRE::HYPRE
+)
+
+if (REMHOS_USE_CALIPER)
+    target_compile_definitions(Remhos PUBLIC REMHOS_USE_CALIPER)
+    target_link_libraries(Remhos PUBLIC caliper adiak::adiak)
+endif()
+
+# Executables *****************************************************************
+if (MFEM_USE_HIP)
+    set_source_files_properties(remhos_main.cpp PROPERTIES LANGUAGE HIP)
+endif()
+add_executable(remhos_main remhos_main.cpp)
+add_dependencies(remhos_main copy_mesh_files)
+target_link_libraries(remhos_main PRIVATE Remhos)
+
+# Install *********************************************************************
+install(TARGETS remhos_main DESTINATION bin)
+install(DIRECTORY data/ DESTINATION data)
+
+# Testing *********************************************************************
 enable_testing()
+
 function(add_remhos_test name)
-    set(file ${name}.cpp)
-    set(target ${name})
-    list(LENGTH ARGN ARGN_COUNT)
-    if(ARGN_COUNT GREATER 0) 
-        list(GET ARGN 0 extra)
-        string(APPEND name "_" ${extra})
-        string(APPEND target "_" ${extra})
+    add_executable(${name} ${name}.cpp)
+    add_dependencies(${name} copy_mesh_files)
+    target_link_libraries(${name} PRIVATE Remhos)
+    if (MFEM_USE_HIP)
+        set_source_files_properties(${name}.cpp PROPERTIES LANGUAGE HIP)
     endif()
-    message(STATUS "Adding target: ${target}")
-    add_executable(${target} ${file})
-    add_dependencies(${target} copy_mesh_files)
-    target_link_libraries(${target} Remhos -lmpi -lmfem -lhypre -lmetis -lfmt)
-if (${CMAKE_SYSTEM_NAME} MATCHES "Linux")
-    target_link_directories(${target} PUBLIC /usr/lib/x86_64-linux-gnu) 
-elseif(${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
-    target_link_directories(${target} PUBLIC /opt/homebrew/opt/openmpi/lib
-                                          /opt/homebrew/opt/metis/lib
-                                          /opt/homebrew/opt/hypre/lib
-                                          /opt/homebrew/opt/fmt/lib) 
-endif()
-    target_link_directories(${target} PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/../mfem)
-    message(STATUS "Adding test: ${target}_n1")
-    add_test(NAME ${target}_n1  COMMAND mpirun -n 1 ${target} ${extra})
-    message(STATUS "Adding test: ${target}_n3")
-    add_test(NAME ${target}_n3 COMMAND mpirun -n 3 ${target})
+    add_test(NAME ${name}_n1
+        COMMAND ${MPIEXEC_EXECUTABLE} ${MPIEXEC_NUMPROC_FLAG} 1 $<TARGET_FILE:${name}>)
+    add_test(NAME ${name}_n3
+        COMMAND ${MPIEXEC_EXECUTABLE} ${MPIEXEC_NUMPROC_FLAG} 3 $<TARGET_FILE:${name}>)
 endfunction()
 
-add_remhos_test(remhos_main)
-add_remhos_test(remhos_tests)
\ No newline at end of file
+add_test(NAME remhos_main_n1
+    COMMAND ${MPIEXEC_EXECUTABLE} ${MPIEXEC_NUMPROC_FLAG} 1 $<TARGET_FILE:remhos_main>)
+add_test(NAME remhos_main_n3
+    COMMAND ${MPIEXEC_EXECUTABLE} ${MPIEXEC_NUMPROC_FLAG} 3 $<TARGET_FILE:remhos_main>)
+
+add_remhos_test(remhos_tests)
diff --git a/remhos.cpp b/remhos.cpp
index 693d826..b8b8958 100644
--- a/remhos.cpp
+++ b/remhos.cpp
@@ -216,9 +216,9 @@ int main(int argc, char *argv[])
 
 MFEM_EXPORT int remhos(int argc, char *argv[], double &final_mass_u)
 {
-   // Initialize MPI.
-   mfem::MPI_Session mpi(argc, argv);
-   const int myid = mpi.WorldRank();
+   // Initialize MPI (skip if already initialized, e.g. when called from a test harness).
+   if (!mfem::Mpi::IsInitialized()) { mfem::Mpi::Init(argc, argv); }
+   const int myid = mfem::Mpi::WorldRank();
 
    const char *mesh_file = "default";
    int dim = 3;
@@ -351,10 +351,13 @@ MFEM_EXPORT int remhos(int argc, char *argv[], double &final_mass_u)
    const char * allocator_name = REMHOS_DEVICE_ALLOCATOR_NAME;
    size_t umpire_dev_pool_size = ((size_t) dev_pool_size) * 1024 * 1024 * 1024;
    size_t umpire_dev_block_size = 1024 * 1024;
-   rm.makeAllocator<umpire::strategy::QuickPool>(allocator_name,
-                                                 rm.getAllocator("DEVICE"),
-                                                 umpire_dev_pool_size,
-                                                 umpire_dev_block_size);
+   if (!rm.isAllocator(allocator_name))
+   {
+      rm.makeAllocator<umpire::strategy::QuickPool>(allocator_name,
+                                                    rm.getAllocator("DEVICE"),
+                                                    umpire_dev_pool_size,
+                                                    umpire_dev_block_size);
+   }
 
 #ifdef HYPRE_USING_UMPIRE
    HYPRE_SetUmpireDevicePoolName(allocator_name);
diff --git a/remhos_tests.cpp b/remhos_tests.cpp
index 1aa1af5..2845260 100644
--- a/remhos_tests.cpp
+++ b/remhos_tests.cpp
@@ -1,15 +1,18 @@
 #include <algorithm>
+#include <cmath>
+#include <cstring>
 #include <iostream>
 #include <memory>
 #include <sstream>
+#include <vector>
 #include <unistd.h>
 
-// #define DBG_COLOR ::debug::kCyan
-// #include "debug.hpp"
+#include "general/communication.hpp"
+using mfem::real_t;
 
 int remhos(int, char *[], double &);
 
-//// ///////////////////////////////////////////////////////////////////////////
+///////////////////////////////////////////////////////////////////////////////
 template <class T>
 std::enable_if_t<!std::numeric_limits<T>::is_integer, bool>
 AlmostEq(T x, T y, T tolerance = 10.0*std::numeric_limits<T>::epsilon())
@@ -25,83 +28,74 @@ AlmostEq(T x, T y, T tolerance = 10.0*std::numeric_limits<T>::epsilon())
 ///////////////////////////////////////////////////////////////////////////////
 struct Test
 {
-   static constexpr const char *binary = "remhos ";
-   static constexpr const char *common = "-no-vis -vs 1";
-   std::string mesh, options;
-   const double result = 0.0;
-   Test(const char * msh, const char * extra, double result)
-      : mesh(msh), options(std::string(extra) + common), result(result) {}
-   std::string Command() const { return binary + mesh + options; }
+   static constexpr const char *binary = "remhos";
+   static constexpr const char *common =
+      "-dt -1.0 -tf 0.5 -ho 3 -lo 5 -fct 2 -ms 5 -no-vis -vs 1";
+   std::string name, mesh, options;
+   const real_t result = std::numeric_limits<real_t>::signaling_NaN();
+   Test(const char *name, const char *mesh, const char *extra, real_t result)
+      : name(name), mesh(mesh), options(std::string(extra) + " " + common),
+        result(result) {}
+   std::string Command() const
+   {
+      return std::string(binary) + " " + mesh + " " + options;
+   }
 };
 
 ///////////////////////////////////////////////////////////////////////////////
 const Test runs[] =
 {
    {
-      // #0
-      "-m ./data/inline-quad.mesh ",
-      "-p 14 -rs 1 -o 2 -dt -1.0 -tf 0.5 -ho 3 -lo 5 -fct 2 -ms 5 ",
-      0.09711395400387984
+      "quad-14-1-2", // #0
+      "-m ./data/inline-quad.mesh", "-p 14 -rs 1 -o 2",
+      0.0971135253228191
    },
    {
-      // #1, 65536
-      "-m ./data/inline-quad.mesh ",
-      "-p 14 -rs 4 -o 3 -dt -1.0 -tf 0.5 -ho 3 -lo 5 -fct 2 -ms 5 ",
-      0.0930984399257905
+      "quad-14-4-3", // #1
+      "-m ./data/inline-quad.mesh", "-p 14 -rs 4 -o 3",
+      0.0930984398474033
    },
    {
-      // #2, 102400
-      // RHS   kernel time: 5.4988707
-      // L2inv kernel time: 0.94180588
-      // LO    kernel time: 0.028575583
-      // FCT   kernel time: 0.0095909583
-      // Total kernel time: 5.5370372
-      "-m ./data/inline-quad.mesh ",
-      "-p 14 -rs 4 -o 4 -dt -1.0 -tf 0.5 -ho 3 -lo 5 -fct 2 -ms 5 ",
-      0.09237630484178257
+      "quad-14-4-4", // #2
+      "-m ./data/inline-quad.mesh", "-p 14 -rs 4 -o 4",
+      0.0923763049829040
    },
    {
-      // #3
-      "-m ./data/cube01_hex.mesh ",
-      "-p 10 -rs 1 -o 2 -dt -1.0 -tf 0.5 -ho 3 -lo 5 -fct 2 -ms 5 ",
-      0.11972857593296446
+      "cube01-10-1-2", // #3
+      "-m ./data/cube01_hex.mesh", "-p 10 -rs 1 -o 2",
+      0.1197219672304615
    },
    {
-      // #4 Partial assembly
-      "-m ./data/inline-quad.mesh ",
-      "-pa -p 14 -rs 1 -o 2 -dt -1.0 -tf 0.5 -ho 3 -lo 5 -fct 2 -ms 5 ",
-      0.09711395400387984
+      "quad-pa-14-1-2", // #4
+      "-m ./data/inline-quad.mesh", "-pa -p 14 -rs 1 -o 2",
+      0.0971135252706320
    },
    {
-      // #5 Partial assembly
-      "-m ./data/inline-quad.mesh ",
-      "-pa -p 14 -rs 4 -o 2 -dt -1.0 -tf 0.5 -ho 3 -lo 5 -fct 2 -ms 5 ",
-      0.09185717760402806
+      "quad-pa-14-4-2", // #5
+      "-m ./data/inline-quad.mesh", "-pa -p 14 -rs 4 -o 2",
+      0.0918571775667415
    },
    {
-      // #7: 3D PA
-      "-m ./data/cube01_hex.mesh ",
-      "-pa -p 10 -rs 3 -o 3 -dt -1.0 -tf 0.5 -ho 3 -lo 5 -fct 2 -ms 1 ",
-      0.11601536511552431
+      "cube01-pa-10-2-3", // #6
+      "-m ./data/cube01_hex.mesh", "-pa -p 10 -rs 2 -o 3",
+      0.1162578642211454
    },
    {
-      // #8
-      "-m ./data/star-q2.mesh ",
-      "-pa -p 14 -rs 1 -o 3 -dt -1.0 -tf 0.5 -ho 3 -lo 5 -fct 2 -ms 5 ",
-      0.8069675186775516
+      "star-q2-pa-14-1-3", // #7
+      "-m ./data/star-q2.mesh", "-pa -p 14 -rs 1 -o 3",
+      0.7975688080682961
    },
    {
-      // #9, 🔥 debug device 🔥 (last or !dup)
-      "-m ./data/inline-quad.mesh ",
-      "-d debug -pa -p 14 -rs 1 -o 2 -dt -1.0 -tf 0.5 -ho 3 -lo 5 -fct 2 -ms 5 ",
-      0.09711395400387984
+      "debug-quad-14-1-2", // #8
+      "-m ./data/inline-quad.mesh", "-d debug -pa -p 14 -rs 1 -o 2",
+      0.0971135252706320
    },
 #ifdef MFEM_USE_CUDA
    {
-      // #10
-      "-m ./data/inline-quad.mesh ",
-      "-d cuda -pa -p 14 -rs 1 -o 2 -dt -1.0 -tf 0.5 -ho 3 -lo 5 -fct 2 -ms 5 ",
-      0.09711395400387984
+      "cuda-quad-14-1-2",
+      "-m ./data/inline-quad.mesh",
+      "-d cuda -pa -p 14 -rs 1 -o 2",
+      0.0971135252706320
    },
 #endif
 };
@@ -133,17 +127,20 @@ int RemhosTest(const Test & test)
    double final_mass_u{};
    remhos(args.size()-1, args.data(), final_mass_u);
 
-   // dbg("final_mass_u: {} vs. {}", final_mass_u, test.result);
+   if (AlmostEq(final_mass_u, test.result)) { return EXIT_SUCCESS; }
 
-   if (AlmostEq(final_mass_u, test.result)) { return std::cout << "✅" << std::endl, EXIT_SUCCESS; }
-
-   return  std::cout << "❌" << std::endl, EXIT_FAILURE;
+   mfem::err << "❌ " << test.name
+             << std::fixed << std::setprecision(16)
+             << ": final_mass_u: " << final_mass_u
+             << " vs. " << test.result
+             << std::endl;
+   return EXIT_FAILURE;
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 int main(int argc, char* argv[]) try
 {
-   // dbgClearScreen(), dbg();
+   mfem::Mpi::Init(argc, argv);
 
    int opt;
    int test = -1;
@@ -178,4 +175,4 @@ catch (std::exception& e)
    std::cerr << "\033[31m..xxxXXX[ERROR]XXXxxx.." << std::endl;
    std::cerr << "\033[31m{}" << e.what() << std::endl;
    return EXIT_FAILURE;
-}
\ No newline at end of file
+}