diff --git a/cmake/SpecMiCPDepends.cmake b/cmake/SpecMiCPDepends.cmake
index f040af6..6366c0d 100644
--- a/cmake/SpecMiCPDepends.cmake
+++ b/cmake/SpecMiCPDepends.cmake
@@ -1,42 +1,55 @@
 
 # Eigen
 # -----
 
 find_package(Eigen3 REQUIRED)  # This module comes from the Eigen3 Package
 message(STATUS "Eigen3 version ${EIGEN3_VERSION}")
 
 # optional
 find_package(Eigen3Unsupported)
 
 add_library(Eigen::eigen INTERFACE IMPORTED)
 set_property(TARGET Eigen::eigen PROPERTY
     INTERFACE_INCLUDE_DIRECTORIES ${EIGEN3_INCLUDE_DIR})
 
 
 
 # HDF5
 # ----
 
 # HDF5 is required and used by all modules for output
 #
 # Only the C serial API is used
 find_package(HDF5 REQUIRED COMPONENTS C)
 
 add_library(HDF5::hdf5 UNKNOWN IMPORTED)
 set_property(TARGET HDF5::hdf5 PROPERTY
     INTERFACE_INCLUDE_DIRECTORIES ${HDF5_INCLUDE_DIRS}
 )
 set_property(TARGET HDF5::hdf5 PROPERTY
     IMPORTED_LOCATION ${HDF5_C_LIBRARY_hdf5}
 )
 
 # Yaml-cpp
 # --------
 
 # YAML-cpp library is required and used by all modules for configuration
 # and data storage
 
 # YAML-CPP does not provide a CMake find module.
 # Instead, we use pkgconfig
 include(FindPkgConfig)
 pkg_check_modules(YAML REQUIRED IMPORTED_TARGET yaml-cpp>=0.5)
+
+# cmake < 3.6
+
+if(NOT TARGET PkgConfig::YAML)
+    add_library(PkgConfig::YAML UNKNOWN IMPORTED)
+    set_property(TARGET PkgConfig::YAML PROPERTY
+        INTERFACE_INCLUDE_DIRECTORIES ${YAML_INCLUDE_DIRS}
+    )
+    set_property(TARGET PkgConfig::YAML PROPERTY
+        IMPORTED_LOCATION ${YAML_LIBRARY_DIRS}/${YAML_LIBRARIES}
+    )
+endif()
+
diff --git a/src/specmicp_database/CMakeLists.txt b/src/specmicp_database/CMakeLists.txt
index ef481bb..baee654 100644
--- a/src/specmicp_database/CMakeLists.txt
+++ b/src/specmicp_database/CMakeLists.txt
@@ -1,138 +1,138 @@
 # The database
 # ============
 
 
 # var to store the files
 
 set(specmicp_database_srcs ""
     CACHE INTERNAL "specmicp_database files" FORCE)
 
 set(specmicp_database_headers ""
     CACHE INTERNAL "specmicp_database headers" FORCE
 )
 
 # macro to add to vars
 
 macro(add_to_database_srcs_list LIST_NAME)
     set(tmp "")
     foreach (src ${${LIST_NAME}})
         list(APPEND tmp ${CMAKE_CURRENT_SOURCE_DIR}/${src})
     endforeach(src)
     set(specmicp_database_srcs "${specmicp_database_srcs};${tmp}" CACHE INTERNAL
             "specmicp_database files" FORCE)
 endmacro(add_to_database_srcs_list)
 
 
 macro(add_to_database_headers_list LIST_NAME)
     set( tmp "")
     foreach(header ${${LIST_NAME}})
        LIST(APPEND tmp ${CMAKE_CURRENT_SOURCE_DIR}/${header})
     endforeach(header)
     set(specmicp_database_headers "${specmicp_database_headers};${tmp}"
             CACHE INTERNAL "specmicp_database headers" FORCE)
 endmacro(add_to_database_headers_list)
 
 # database libraries
 # ------------------
 
 set(specmicp_database_main_srcs
     appender.cpp
     aqueous_selector.cpp
     data_container.cpp
     database.cpp
     mineral_selector.cpp
     module.cpp
     oxydo_selector.cpp
     reader_common.cpp
     selector.cpp
     switch_basis.cpp
     unknown_class.cpp
     yaml_reader.cpp
     yaml_writer.cpp
 )
 
 set(specmicp_database_main_headers
     appender.hpp
     aqueous_selector.hpp
     config_database.hpp
     data_container.hpp
     database.hpp
     database_fwd.hpp
     database_holder.hpp
     errors.hpp
     mineral_selector.hpp
     module.hpp
     oxydo_selector.hpp
     reader_common.hpp
     section_name.hpp
     selector.hpp
     switch_basis.hpp
     unknown_class.hpp
     yaml_reader.hpp
     yaml_writer.hpp
 )
 
 add_to_database_srcs_list(specmicp_database_main_srcs)
 add_to_database_headers_list(specmicp_database_main_headers)
 
 INSTALL(FILES ${specmicp_database_main_headers}
     DESTINATION ${INCLUDE_INSTALL_DIR}/specmicp_database
 )
 
 #
 add_subdirectory(io)
 add_subdirectory(species)
 
 # build library
 # =============
 
 set_visibility_flag(${specmicp_database_srcs})
 set_pgo_flag(${specmicp_database_srcs})
 
 add_library(objspecmicp_database OBJECT
     ${specmicp_database_srcs}
     ${specmicp_database_headers}
 )
 target_include_directories(objspecmicp_database PUBLIC ${EIGEN3_INCLUDE_DIR} ${HDF5_INCLUDE_DIRS} ${YAML_INCLUDE_DIRS})
 set_property(TARGET objspecmicp_database PROPERTY POSITION_INDEPENDENT_CODE 1)
 set_property(TARGET objspecmicp_database PROPERTY CXX_STANDARD ${SPECMICP_CXX_STANDARD})
 set_property(TARGET objspecmicp_database PROPERTY CXX_STANDARD_REQUIRED ON)
 
 
 add_library(specmicp_database SHARED $<TARGET_OBJECTS:objspecmicp_database>)
 target_link_libraries(specmicp_database PUBLIC specmicp_common)
-target_link_libraries(specmicp_database PRIVATE ${YAML_LIBRARIES})
+target_link_libraries(specmicp_database PUBLIC PkgConfig::YAML)
 spc_set_cxx_version_interface(specmicp_database)
 install(TARGETS specmicp_database
     EXPORT ${SPECMICP_TARGET}
     LIBRARY DESTINATION ${LIBRARY_INSTALL_DIR}
 )
 
 
 # static libraries
 # ----------------
 
 if(SPECMICP_BUILD_STATIC)
     add_library(specmicp_database_static STATIC
         $<TARGET_OBJECTS:objspecmicp_database>
     )
 
     install(TARGETS specmicp_database_static
         EXPORT ${SPECMICP_TARGET}
         ARCHIVE DESTINATION ${STATIC_LIBRARY_INSTALL_DIR}
     )
 else()
     add_library(specmicp_database_static
         EXCLUDE_FROM_ALL STATIC
         $<TARGET_OBJECTS:objspecmicp_database>
         )
 endif()
 
 set_target_properties(specmicp_database_static PROPERTIES
         OUTPUT_NAME specmicp_database
 )
 spc_set_cxx_version_interface(specmicp_database_static)
 target_link_libraries(specmicp_database_static PUBLIC specmicp_common_static)
-target_link_libraries(specmicp_database_static PUBLIC ${YAML_LIBRARIES})
+target_link_libraries(specmicp_database_static PUBLIC PkgConfig::YAML)