diff --git a/CMakeLists.txt b/CMakeLists.txt
index 11fb0814..569e3bcf 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -99,12 +99,12 @@ ecbuild_add_option( FEATURE HEALPIX_EXAMPLES
 
 ###  Definitions used by the output manager
 ecbuild_add_option( FEATURE OUTPUT_MANAGER
-	                DEFAULT ON
+	                  DEFAULT ON
                     DESCRIPTION "Build the output manager" )
 
 ecbuild_add_option( FEATURE OUTPUT_MANAGER_ENCODER_REPORT
                     CONDITION HAVE_OUTPUT_MANAGER
-		            DEFAULT OFF
+		                DEFAULT OFF
                     DESCRIPTION "Enable generation of the encoding report" )
 
 ecbuild_add_option( FEATURE OUTPUT_MANAGER_TOOL
@@ -114,7 +114,7 @@ ecbuild_add_option( FEATURE OUTPUT_MANAGER_TOOL
 
 ### export package info
 set( MULTIO_CONFIG_DIR     share/multio/config )
-set( MULTIOM_CONFIG_DIR     share/multiom )
+set( MULTIOM_CONFIG_DIR    share/multiom )
 set( MULTIO_INCLUDE_DIRS   ${CMAKE_CURRENT_SOURCE_DIR}/src ${CMAKE_CURRENT_BINARY_DIR}/src )
 set( MULTIO_LIBRARIES      multio )
 
diff --git a/src/multiom/CMakeLists.txt b/src/multiom/CMakeLists.txt
index ae38f6e4..cdcd81ef 100644
--- a/src/multiom/CMakeLists.txt
+++ b/src/multiom/CMakeLists.txt
@@ -101,6 +101,7 @@ set( DOFFSET "     ")
 #
 # + ADD SUB-DIRECTORIES
 # =====================
+add_subdirectory( api )
 add_subdirectory( common )
 add_subdirectory( configuration )
 add_subdirectory( containers )
@@ -123,6 +124,7 @@ add_subdirectory( tools )
 # + ADD LOCAL FILES
 # =================
 list( APPEND output_manager_src
+  ${MULTIOM_API_SOURCES}
   ${MULTIOM_COMMON_SOURCES}
   ${MULTIOM_CONFIGURATION_SOURCES}
   ${MULTIOM_CONTAINERS_SOURCES}
diff --git a/src/multiom/api/CMakeLists.txt b/src/multiom/api/CMakeLists.txt
new file mode 100644
index 00000000..1537e818
--- /dev/null
+++ b/src/multiom/api/CMakeLists.txt
@@ -0,0 +1,23 @@
+set(MULTIOM_API_DIR ${CMAKE_CURRENT_SOURCE_DIR})
+
+# Enter in the module
+message("${OFFSET} + API sources: ${MULTIOM_API_DIR}")
+
+# Recursive print
+set(OFFSET ${OFFSET}${DOFFSET})
+
+# Collect source files in module2
+set( MULTIOM_API_SOURCES
+  ${MULTIOM_API_DIR}/api_wrapper_mod.F90
+  CACHE INTERNAL "List of all sources in API directory"
+)
+
+# Optionally, message what has been appended for debugging
+foreach(source_file IN LISTS MULTIOM_API_SOURCES)
+
+    # Extract the filename (without the directory)
+    get_filename_component(filename ${source_file} NAME)
+
+    # Print the filename
+    message("${OFFSET}    - ${filename}")
+endforeach()
\ No newline at end of file
diff --git a/src/multiom/api/api_wrapper_mod.F90 b/src/multiom/api/api_wrapper_mod.F90
new file mode 100644
index 00000000..ac4bb206
--- /dev/null
+++ b/src/multiom/api/api_wrapper_mod.F90
@@ -0,0 +1,401 @@
+! Include preprocessor utils
+#include "output_manager_preprocessor_utils.h"
+#include "output_manager_preprocessor_trace_utils.h"
+#include "output_manager_preprocessor_logging_utils.h"
+#include "output_manager_preprocessor_errhdl_utils.h"
+
+
+#define PP_FILE_NAME 'api_wrapper_mod_mod.F90'
+#define PP_SECTION_TYPE 'MODULE'
+#define PP_SECTION_NAME 'GENERAL_UTILS_MOD'
+MODULE API_WRAPPER_MOD
+
+  ! USE :: ENCODERS_MAP_MOD, ONLY: ENCODERS_MAP_T
+  ! USE :: ENCODERS_MAP_MOD, ONLY: MARS_MAP_T
+  ! USE :: ENCODERS_MAP_MOD, ONLY: PAR_MAP_T
+
+IMPLICIT NONE
+
+!> Default visibility of the module
+PRIVATE
+
+! In order to exchange data with c, we need to define the following maps
+! TYPE(ENCODERS_MAP_T) :: ENCODERS_MAP
+! TYPE(ENCODERS_MAP_T) :: MARS_MAP
+! TYPE(ENCODERS_MAP_T) :: PAR_MAP
+
+
+! Whitelist of public symbols
+PUBLIC :: MULTIO_GRIB2_ENCODER_OPEN
+PUBLIC :: MULTIO_GRIB2_ENCODER_CLOSE
+PUBLIC :: MULTIO_GRIB2_ENCODER_ENCODE64
+PUBLIC :: MULTIO_GRIB2_ENCODER_ENCODE32
+
+CONTAINS
+
+#define PP_PROCEDURE_TYPE 'FUNCTION'
+#define PP_PROCEDURE_NAME 'TOUPPER'
+PP_THREAD_SAFE FUNCTION MULTIO_GRIB2_ENCODER_OPEN( OPTIONS, MULTIO_GRIB2 ) &
+ BIND(C,NAME='multio_grib2_encoder_open') RESULT(RET)
+
+  !> Symbols imported from intrinsic modules.
+  USE, INTRINSIC :: ISO_C_BINDING, ONLY: C_INT
+  USE, INTRINSIC :: ISO_C_BINDING, ONLY: C_PTR
+  USE, INTRINSIC :: ISO_C_BINDING, ONLY: C_NULL_PTR
+
+  ! Symbols imported from other modules within the project.
+  USE :: DATAKINDS_DEF_MOD, ONLY: JPIB_K
+  USE :: HOOKS_MOD,         ONLY: HOOKS_T
+
+  ! Symbols imported by the preprocessor for debugging purposes
+  PP_DEBUG_USE_VARS
+
+  ! Symbols imported by the preprocessor for logging purposes
+  PP_LOG_USE_VARS
+
+  ! Symbols imported by the preprocessor for tracing purposes
+  PP_TRACE_USE_VARS
+
+IMPLICIT NONE
+
+  !> Dummy arguments
+  TYPE(C_PTR), VALUE, INTENT(IN)    :: OPTIONS
+  TYPE(C_PTR),        INTENT(INOUT) :: MULTIO_GRIB2
+
+  !> Function result
+  INTEGER(KIND=C_INT) :: RET
+
+  ! Local variables declared by the preprocessor for debugging purposes
+  PP_DEBUG_DECL_VARS
+
+  ! Local variables declared by the preprocessor for logging purposes
+  PP_LOG_DECL_VARS
+
+  ! Local variables declared by the preprocessor for tracing purposes
+  PP_TRACE_DECL_VARS
+
+  ! Trace begin of procedure
+  PP_TRACE_ENTER_PROCEDURE()
+
+  ! Initialization of good path return value
+  PP_SET_ERR_SUCCESS( RET )
+
+
+  ! Trace end of procedure (on success)
+  PP_TRACE_EXIT_PROCEDURE_ON_SUCCESS()
+
+  ! Exit point (On success)
+  RETURN
+
+! Error handler
+PP_ERROR_HANDLER
+
+  ! Initialization of bad path return value
+  PP_SET_ERR_FAILURE( RET )
+
+  ! TODO: Add error handling code here
+
+  RETURN
+
+END FUNCTION MULTIO_GRIB2_ENCODER_OPEN
+#undef PP_PROCEDURE_NAME
+#undef PP_PROCEDURE_TYPE
+
+
+
+#define PP_PROCEDURE_TYPE 'FUNCTION'
+#define PP_PROCEDURE_NAME 'TOUPPER'
+PP_THREAD_SAFE FUNCTION MULTIO_GRIB2_ENCODER_CLOSE( MULTIO_GRIB2 ) &
+ BIND(C,NAME='multio_grib2_encoder_close') RESULT(RET)
+
+  !> Symbols imported from intrinsic modules.
+  USE, INTRINSIC :: ISO_C_BINDING, ONLY: C_INT
+  USE, INTRINSIC :: ISO_C_BINDING, ONLY: C_PTR
+  USE, INTRINSIC :: ISO_C_BINDING, ONLY: C_NULL_PTR
+
+  ! Symbols imported from other modules within the project.
+  USE :: DATAKINDS_DEF_MOD, ONLY: JPIB_K
+  USE :: HOOKS_MOD,         ONLY: HOOKS_T
+
+  ! Symbols imported by the preprocessor for debugging purposes
+  PP_DEBUG_USE_VARS
+
+  ! Symbols imported by the preprocessor for logging purposes
+  PP_LOG_USE_VARS
+
+  ! Symbols imported by the preprocessor for tracing purposes
+  PP_TRACE_USE_VARS
+
+IMPLICIT NONE
+
+  !> Dummy arguments
+  TYPE(C_PTR), VALUE, INTENT(IN) :: MULTIO_GRIB2
+
+  !> Function result
+  INTEGER(KIND=C_INT) :: RET
+
+  ! Local variables declared by the preprocessor for debugging purposes
+  PP_DEBUG_DECL_VARS
+
+  ! Local variables declared by the preprocessor for logging purposes
+  PP_LOG_DECL_VARS
+
+  ! Local variables declared by the preprocessor for tracing purposes
+  PP_TRACE_DECL_VARS
+
+  ! Trace begin of procedure
+  PP_TRACE_ENTER_PROCEDURE()
+
+  ! Initialization of good path return value
+  PP_SET_ERR_SUCCESS( RET )
+
+
+  ! Trace end of procedure (on success)
+  PP_TRACE_EXIT_PROCEDURE_ON_SUCCESS()
+
+  ! Exit point (On success)
+  RETURN
+
+! Error handler
+PP_ERROR_HANDLER
+
+  ! Initialization of bad path return value
+  PP_SET_ERR_FAILURE( RET )
+
+  ! TODO: Add error handling code here
+
+  RETURN
+
+END FUNCTION MULTIO_GRIB2_ENCODER_CLOSE
+#undef PP_PROCEDURE_NAME
+#undef PP_PROCEDURE_TYPE
+
+
+#define PP_PROCEDURE_TYPE 'FUNCTION'
+#define PP_PROCEDURE_NAME 'MULTIO_GRIB2_ENCODER_ENCODE64'
+PP_THREAD_SAFE FUNCTION MULTIO_GRIB2_ENCODER_ENCODE64( MULTIO_GRIB2, MARS_DICT, PAR_DICT, VALUES, DATA_LEN, GRIB_HANDLE ) &
+ BIND(C,NAME='multio_grib2_encoder_encode64') RESULT(RET)
+
+  !> Symbols imported from intrinsic modules.
+  USE, INTRINSIC :: ISO_C_BINDING, ONLY: C_DOUBLE
+  USE, INTRINSIC :: ISO_C_BINDING, ONLY: C_INT
+  USE, INTRINSIC :: ISO_C_BINDING, ONLY: C_PTR
+  USE, INTRINSIC :: ISO_C_BINDING, ONLY: C_LONG_LONG
+  USE, INTRINSIC :: ISO_C_BINDING, ONLY: C_NULL_PTR
+  USE, INTRINSIC :: ISO_C_BINDING, ONLY: C_ASSOCIATED
+  USE, INTRINSIC :: ISO_C_BINDING, ONLY: C_F_POINTER
+
+  ! Symbols imported from other modules within the project.
+  USE :: DATAKINDS_DEF_MOD, ONLY: JPIB_K
+  USE :: HOOKS_MOD,         ONLY: HOOKS_T
+
+  ! Symbols imported by the preprocessor for debugging purposes
+  PP_DEBUG_USE_VARS
+
+  ! Symbols imported by the preprocessor for logging purposes
+  PP_LOG_USE_VARS
+
+  ! Symbols imported by the preprocessor for tracing purposes
+  PP_TRACE_USE_VARS
+
+IMPLICIT NONE
+
+  !> Dummy arguments
+  TYPE(C_PTR),         VALUE, INTENT(IN) :: MULTIO_GRIB2
+  TYPE(C_PTR),         VALUE, INTENT(IN) :: MARS_DICT
+  TYPE(C_PTR),         VALUE, INTENT(IN) :: PAR_DICT
+  TYPE(C_PTR),         VALUE, INTENT(IN) :: VALUES
+  INTEGER(KIND=C_INT), VALUE, INTENT(IN) :: DATA_LEN
+  TYPE(C_PTR),         VALUE, INTENT(IN) :: GRIB_HANDLE
+
+  !> Function result
+  INTEGER(KIND=C_INT) :: RET
+
+  !> Local variables
+  REAL(KIND=C_DOUBLE), DIMENSION(:), POINTER :: VALUES_ARRAY32
+  INTEGER(KIND=C_LONG_LONG), POINTER :: ENCODER_ID
+  INTEGER(KIND=C_LONG_LONG), POINTER :: MARS_ID
+  INTEGER(KIND=C_LONG_LONG), POINTER :: PAR_ID
+
+  !> Local error flags
+  INTEGER(KIND=JPIB_K), PARAMETER :: ERRFLAG_WRONG_DATA_LEN=1_JPIB_K
+  INTEGER(KIND=JPIB_K), PARAMETER :: ERRFLAG_VALUES_IS_NULL_POINTER=2_JPIB_K
+  INTEGER(KIND=JPIB_K), PARAMETER :: ERRFLAG_MULTIO_GRIB2_IS_NULL_POINTER=3_JPIB_K
+  INTEGER(KIND=JPIB_K), PARAMETER :: ERRFLAG_MARS_DICT_IS_NULL_POINTER=4_JPIB_K
+  INTEGER(KIND=JPIB_K), PARAMETER :: ERRFLAG_PAR_DICT_IS_NULL_POINTER=5_JPIB_K
+  INTEGER(KIND=JPIB_K), PARAMETER :: ERRFLAG_GRIB_HANDLE_IS_NULL_POINTER=6_JPIB_K
+
+  ! Local variables declared by the preprocessor for debugging purposes
+  PP_DEBUG_DECL_VARS
+
+  ! Local variables declared by the preprocessor for logging purposes
+  PP_LOG_DECL_VARS
+
+  ! Local variables declared by the preprocessor for tracing purposes
+  PP_TRACE_DECL_VARS
+
+  ! Trace begin of procedure
+  PP_TRACE_ENTER_PROCEDURE()
+
+  ! Initialization of good path return value
+  RET = 0_C_INT
+
+  !> Error handling
+  PP_DEBUG_CRITICAL_COND_THROW( DATA_LEN .LE. 0, ERRFLAG_WRONG_DATA_LEN )
+  PP_DEBUG_CRITICAL_COND_THROW( .NOT.C_ASSOCIATED(VALUES), ERRFLAG_VALUES_IS_NULL_POINTER )
+  PP_DEBUG_CRITICAL_COND_THROW( .NOT.C_ASSOCIATED(MULTIO_GRIB2), ERRFLAG_MULTIO_GRIB2_IS_NULL_POINTER )
+  PP_DEBUG_CRITICAL_COND_THROW( .NOT.C_ASSOCIATED(MARS_DICT), ERRFLAG_MARS_DICT_IS_NULL_POINTER )
+  PP_DEBUG_CRITICAL_COND_THROW( .NOT.C_ASSOCIATED(PAR_DICT), ERRFLAG_PAR_DICT_IS_NULL_POINTER )
+  PP_DEBUG_CRITICAL_COND_THROW( .NOT.C_ASSOCIATED(GRIB_HANDLE), ERRFLAG_GRIB_HANDLE_IS_NULL_POINTER )
+
+  !> Cast the VALUES pointer to a real array
+  CALL C_F_POINTER( VALUES, VALUES_ARRAY32, [DATA_LEN] )
+
+  !> Get encoder handle from the c pointer
+  CALL C_F_POINTER( MULTIO_GRIB2, ENCODER_ID )
+
+  !> Get mars dictionary handle from the c pointer
+  CALL C_F_POINTER( MARS_DICT, MARS_ID )
+
+  !> Parameterization handle from the c pointer
+  CALL C_F_POINTER( PAR_DICT, PAR_ID )
+
+  !> 
+
+  ! Trace end of procedure (on success)
+  PP_TRACE_EXIT_PROCEDURE_ON_SUCCESS()
+
+  ! Exit point (On success)
+  RETURN
+
+! Error handler
+PP_ERROR_HANDLER
+
+  ! Initialization of bad path return value
+  PP_SET_ERR_FAILURE( RET )
+
+  ! TODO: Add error handling code here
+
+  RETURN
+
+END FUNCTION MULTIO_GRIB2_ENCODER_ENCODE64
+#undef PP_PROCEDURE_NAME
+#undef PP_PROCEDURE_TYPE
+
+
+#define PP_PROCEDURE_TYPE 'FUNCTION'
+#define PP_PROCEDURE_NAME 'MULTIO_GRIB2_ENCODER_ENCODE32'
+PP_THREAD_SAFE FUNCTION MULTIO_GRIB2_ENCODER_ENCODE32( MULTIO_GRIB2, MARS_DICT, PAR_DICT, VALUES, DATA_LEN, GRIB_HANDLE ) &
+ BIND(C,NAME='multio_grib2_encoder_encode32') RESULT(RET)
+
+  !> Symbols imported from intrinsic modules.
+  USE, INTRINSIC :: ISO_C_BINDING, ONLY: C_FLOAT
+  USE, INTRINSIC :: ISO_C_BINDING, ONLY: C_INT
+  USE, INTRINSIC :: ISO_C_BINDING, ONLY: C_PTR
+  USE, INTRINSIC :: ISO_C_BINDING, ONLY: C_LONG_LONG
+  USE, INTRINSIC :: ISO_C_BINDING, ONLY: C_NULL_PTR
+  USE, INTRINSIC :: ISO_C_BINDING, ONLY: C_ASSOCIATED
+  USE, INTRINSIC :: ISO_C_BINDING, ONLY: C_F_POINTER
+
+  ! Symbols imported from other modules within the project.
+  USE :: DATAKINDS_DEF_MOD, ONLY: JPIB_K
+  USE :: HOOKS_MOD,         ONLY: HOOKS_T
+
+  ! Symbols imported by the preprocessor for debugging purposes
+  PP_DEBUG_USE_VARS
+
+  ! Symbols imported by the preprocessor for logging purposes
+  PP_LOG_USE_VARS
+
+  ! Symbols imported by the preprocessor for tracing purposes
+  PP_TRACE_USE_VARS
+
+IMPLICIT NONE
+
+  !> Dummy arguments
+  TYPE(C_PTR),         VALUE, INTENT(IN) :: MULTIO_GRIB2
+  TYPE(C_PTR),         VALUE, INTENT(IN) :: MARS_DICT
+  TYPE(C_PTR),         VALUE, INTENT(IN) :: PAR_DICT
+  TYPE(C_PTR),         VALUE, INTENT(IN) :: VALUES
+  INTEGER(KIND=C_INT), VALUE, INTENT(IN) :: DATA_LEN
+  TYPE(C_PTR),         VALUE, INTENT(IN) :: GRIB_HANDLE
+
+  !> Function result
+  INTEGER(KIND=C_INT) :: RET
+
+  !> Local variables
+  REAL(KIND=C_FLOAT), DIMENSION(:), POINTER :: VALUES_ARRAY32
+  INTEGER(KIND=C_LONG_LONG), POINTER :: ENCODER_ID
+  INTEGER(KIND=C_LONG_LONG), POINTER :: MARS_ID
+  INTEGER(KIND=C_LONG_LONG), POINTER :: PAR_ID
+
+  !> Local error flags
+  INTEGER(KIND=JPIB_K), PARAMETER :: ERRFLAG_WRONG_DATA_LEN=1_JPIB_K
+  INTEGER(KIND=JPIB_K), PARAMETER :: ERRFLAG_VALUES_IS_NULL_POINTER=2_JPIB_K
+  INTEGER(KIND=JPIB_K), PARAMETER :: ERRFLAG_MULTIO_GRIB2_IS_NULL_POINTER=3_JPIB_K
+  INTEGER(KIND=JPIB_K), PARAMETER :: ERRFLAG_MARS_DICT_IS_NULL_POINTER=4_JPIB_K
+  INTEGER(KIND=JPIB_K), PARAMETER :: ERRFLAG_PAR_DICT_IS_NULL_POINTER=5_JPIB_K
+  INTEGER(KIND=JPIB_K), PARAMETER :: ERRFLAG_GRIB_HANDLE_IS_NULL_POINTER=6_JPIB_K
+
+  ! Local variables declared by the preprocessor for debugging purposes
+  PP_DEBUG_DECL_VARS
+
+  ! Local variables declared by the preprocessor for logging purposes
+  PP_LOG_DECL_VARS
+
+  ! Local variables declared by the preprocessor for tracing purposes
+  PP_TRACE_DECL_VARS
+
+  ! Trace begin of procedure
+  PP_TRACE_ENTER_PROCEDURE()
+
+  ! Initialization of good path return value
+  RET = 0_C_INT
+
+  !> Error handling
+  PP_DEBUG_CRITICAL_COND_THROW( DATA_LEN .LE. 0, ERRFLAG_WRONG_DATA_LEN )
+  PP_DEBUG_CRITICAL_COND_THROW( .NOT.C_ASSOCIATED(VALUES), ERRFLAG_VALUES_IS_NULL_POINTER )
+  PP_DEBUG_CRITICAL_COND_THROW( .NOT.C_ASSOCIATED(MULTIO_GRIB2), ERRFLAG_MULTIO_GRIB2_IS_NULL_POINTER )
+  PP_DEBUG_CRITICAL_COND_THROW( .NOT.C_ASSOCIATED(MARS_DICT), ERRFLAG_MARS_DICT_IS_NULL_POINTER )
+  PP_DEBUG_CRITICAL_COND_THROW( .NOT.C_ASSOCIATED(PAR_DICT), ERRFLAG_PAR_DICT_IS_NULL_POINTER )
+  PP_DEBUG_CRITICAL_COND_THROW( .NOT.C_ASSOCIATED(GRIB_HANDLE), ERRFLAG_GRIB_HANDLE_IS_NULL_POINTER )
+
+  !> Cast the VALUES pointer to a real array
+  CALL C_F_POINTER( VALUES, VALUES_ARRAY32, [DATA_LEN] )
+
+  !> Get encoder handle from the c pointer
+  CALL C_F_POINTER( MULTIO_GRIB2, ENCODER_ID )
+
+  !> Get mars dictionary handle from the c pointer
+  CALL C_F_POINTER( MARS_DICT, MARS_ID )
+
+  !> Parameterization handle from the c pointer
+  CALL C_F_POINTER( PAR_DICT, PAR_ID )
+
+  !> 
+
+  ! Trace end of procedure (on success)
+  PP_TRACE_EXIT_PROCEDURE_ON_SUCCESS()
+
+  ! Exit point (On success)
+  RETURN
+
+! Error handler
+PP_ERROR_HANDLER
+
+  ! Initialization of bad path return value
+  PP_SET_ERR_FAILURE( RET )
+
+  ! TODO: Add error handling code here
+
+  RETURN
+
+END FUNCTION MULTIO_GRIB2_ENCODER_ENCODE32
+#undef PP_PROCEDURE_NAME
+#undef PP_PROCEDURE_TYPE
+
+
+END MODULE API_WRAPPER_MOD
+#undef PP_SECTION_NAME
+#undef PP_SECTION_TYPE
+#undef PP_FILE_NAME
\ No newline at end of file
diff --git a/src/multiom/common/enumerators_mod.F90 b/src/multiom/common/enumerators_mod.F90
index b4022316..11bd36e7 100644
--- a/src/multiom/common/enumerators_mod.F90
+++ b/src/multiom/common/enumerators_mod.F90
@@ -1023,7 +1023,7 @@ MODULE ENUMERATORS_MOD
   PUBLIC :: CFLOATOPFUNCCALL2IFLOATOPFUNCCALL
   PUBLIC :: IIFACES2CIFACES
   PUBLIC :: CIFACES2IIFACES
-  PUBLIC :: IPREF2MSGTYPE
+  PUBLIC :: IPREFIX2IMSGTYPE
   PUBLIC :: IPREFIX2ILEVTYPE
   PUBLIC :: IPARAMTYPE2CPARAMTYPE
   PUBLIC :: CPARAMTYPE2IPARAMTYPE
@@ -1031,8 +1031,8 @@ MODULE ENUMERATORS_MOD
 CONTAINS
 
 #define PP_PROCEDURE_TYPE 'FUNCTION'
-#define PP_PROCEDURE_NAME 'IPREF2MSGTYPE'
-PP_THREAD_SAFE FUNCTION IPREF2MSGTYPE( KPREF, MSGTYPE, HOOKS ) RESULT(RET)
+#define PP_PROCEDURE_NAME 'IPREFIX2IMSGTYPE'
+PP_THREAD_SAFE FUNCTION IPREFIX2IMSGTYPE( KPREF, MSGTYPE, HOOKS ) RESULT(RET)
 
   ! Symbols imported from other modules within the project.
   USE :: DATAKINDS_DEF_MOD, ONLY: JPIB_K
@@ -1130,7 +1130,7 @@ PP_THREAD_SAFE FUNCTION IPREF2MSGTYPE( KPREF, MSGTYPE, HOOKS ) RESULT(RET)
   ! Exit point (on error)
   RETURN
 
-END FUNCTION IPREF2MSGTYPE
+END FUNCTION IPREFIX2IMSGTYPE
 #undef PP_PROCEDURE_NAME
 #undef PP_PROCEDURE_TYPE
 
diff --git a/src/multiom/common/general_utils_mod.F90 b/src/multiom/common/general_utils_mod.F90
index 28086a44..0229a31d 100644
--- a/src/multiom/common/general_utils_mod.F90
+++ b/src/multiom/common/general_utils_mod.F90
@@ -22,11 +22,69 @@ MODULE GENERAL_UTILS_MOD
 PUBLIC :: READ_TYPE_FROM_ENV
 PUBLIC :: READ_YAML_FROM_ENV
 PUBLIC :: CUSTOM_FINDLOC
+PUBLIC :: NEED_FIT_SPECTRUM
 PUBLIC :: TOLOWER
 PUBLIC :: TOUPPER
 
 CONTAINS
 
+
+#define PP_PROCEDURE_TYPE 'FUNCTION'
+#define PP_PROCEDURE_NAME 'NEED_FIT_SPECTRUM'
+PP_THREAD_SAFE FUNCTION NEED_FIT_SPECTRUM( NSMAX, LNFT, HOOKS ) RESULT(RET)
+
+  ! Symbols imported from other modules within the project.
+  USE :: DATAKINDS_DEF_MOD, ONLY: JPIB_K
+  USE :: HOOKS_MOD,         ONLY: HOOKS_T
+
+  ! Symbols imported by the preprocessor for debugging purposes
+  PP_DEBUG_USE_VARS
+
+  ! Symbols imported by the preprocessor for logging purposes
+  PP_LOG_USE_VARS
+
+  ! Symbols imported by the preprocessor for tracing purposes
+  PP_TRACE_USE_VARS
+
+IMPLICIT NONE
+
+  ! Dummy arguments
+  INTEGER(KIND=JPIB_K), INTENT(IN)    :: NSMAX
+  LOGICAL,              INTENT(OUT)   :: LNFT
+  TYPE(HOOKS_T),        INTENT(INOUT) :: HOOKS
+
+  !> Function result
+  INTEGER(KIND=JPIB_K) :: RET
+
+  ! Local variables declared by the preprocessor for debugging purposes
+  PP_DEBUG_DECL_VARS
+
+  ! Local variables declared by the preprocessor for logging purposes
+  PP_LOG_DECL_VARS
+
+  ! Local variables declared by the preprocessor for tracing purposes
+  PP_TRACE_DECL_VARS
+
+  ! Trace begin of procedure
+  PP_TRACE_ENTER_PROCEDURE()
+
+  ! Initialization of good path return value
+  PP_SET_ERR_SUCCESS( RET )
+
+  ! Check if the number of spectral coefficients is greater than 10
+  LNFT = NSMAX .GT. 10
+
+  ! Trace end of procedure (on success)
+  PP_TRACE_EXIT_PROCEDURE_ON_SUCCESS()
+
+  ! Exit point
+  RETURN
+
+END FUNCTION NEED_FIT_SPECTRUM
+#undef PP_PROCEDURE_NAME
+#undef PP_PROCEDURE_TYPE
+
+
 #define PP_PROCEDURE_TYPE 'FUNCTION'
 #define PP_PROCEDURE_NAME 'REPLACE_ENVVAR_IN_STRING'
 PP_THREAD_SAFE FUNCTION REPLACE_ENVVAR_IN_STRING( INPSTR, OUTSTR, HOOKS ) RESULT(RET)
diff --git a/src/multiom/multiom_api.F90 b/src/multiom/multiom_api.F90
index 0fea1dc1..8c2052da 100644
--- a/src/multiom/multiom_api.F90
+++ b/src/multiom/multiom_api.F90
@@ -22,15 +22,44 @@ MODULE MULTIOM_API
   USE :: DATAKINDS_DEF_MOD, ONLY: JPRD_K
 
   ! Enumerators
+  USE :: ENUMERATORS_MOD, ONLY: REPRES_GAUSSIANGRID_E
+  USE :: ENUMERATORS_MOD, ONLY: REPRES_SPHERICALHARMONICS_E
+  USE :: ENUMERATORS_MOD, ONLY: VALUES_SP_E
+  USE :: ENUMERATORS_MOD, ONLY: VALUES_DP_E
+  USE :: ENUMERATORS_MOD, ONLY: ATM_MSG_E
+  USE :: ENUMERATORS_MOD, ONLY: WAM_MSG_E
+
+  ! Enumerators utils
+  USE :: ENUMERATORS_MOD, ONLY: CPREFIX2IPREFIX
   USE :: ENUMERATORS_MOD, ONLY: IPREFIX2ILEVTYPE
+  USE :: ENUMERATORS_MOD, ONLY: IPREFIX2IMSGTYPE
   USE :: ENUMERATORS_MOD, ONLY: ILEVTYPE2CLEVTYPE
+  USE :: ENUMERATORS_MOD, ONLY: CLEVTYPE2ILEVTYPE
   USE :: ENUMERATORS_MOD, ONLY: IREPRES2CREPRES
-  USE :: ENUMERATORS_MOD, ONLY: VALUES_SP_E
-  USE :: ENUMERATORS_MOD, ONLY: VALUES_DP_E
+  USE :: ENUMERATORS_MOD, ONLY: CREPRES2IREPRES
 
-  ! ifs interface
+  ! ifs-interface (datatypes)
+  USE :: IFS_MSG_MOD, ONLY: OM_BASE_MSG_A
   USE :: IFS_MSG_MOD, ONLY: OM_ATM_MSG_T
   USE :: IFS_MSG_MOD, ONLY: OM_WAM_MSG_T
+  USE :: IFS_PAR_MOD, ONLY: PROC_TOPO_T
+  USE :: IFS_PAR_MOD, ONLY: MODEL_PAR_T
+
+  USE :: IFS_PAR_SERIALIZATION_MOD, ONLY: MODEL_PAR_SERIAL_T
+
+  USE :: IFS_TOC_MOD, ONLY: TOC_CONTAINER_T
+  USE :: IFS_TOC_MOD, ONLY: TOC_CREATE_NAME
+  USE :: IFS_TOC_MOD, ONLY: TOC_ENTRY_BASE_T
+  USE :: IFS_TOC_MOD, ONLY: TOC_SIM_INIT_T
+  USE :: IFS_TOC_MOD, ONLY: TOC_ATM_FIELD_T
+  USE :: IFS_TOC_MOD, ONLY: TOC_WAM_FIELD_T
+  USE :: IFS_TOC_MOD, ONLY: TOC_FLUSH_STEP_T
+  USE :: IFS_TOC_MOD, ONLY: TOC_FLUSH_STEP_RST_T
+  USE :: IFS_TOC_MOD, ONLY: TOC_FLUSH_LAST_STEP_T
+  USE :: IFS_TOC_MOD, ONLY: TOC_SIM_END_T
+
+
+  ! ifs-interface (utils)
   USE :: IFS_MSG_MOD, ONLY: MSG_PRINT_ATM
   USE :: IFS_MSG_MOD, ONLY: MSG_PRINT_WAM
   USE :: IFS_MSG_MOD, ONLY: MSG_CREATE_NAME
@@ -38,12 +67,15 @@ MODULE MULTIOM_API
   USE :: IFS_MSG_MOD, ONLY: MSG_READ_ATM
   USE :: IFS_MSG_MOD, ONLY: MSG_READ_WAM
   USE :: IFS_MSG_MOD, ONLY: MSG_CLOSE
-  USE :: IFS_PAR_MOD, ONLY: PROC_TOPO_T
-  USE :: IFS_PAR_MOD, ONLY: MODEL_PAR_T
+
   USE :: IFS_PAR_MOD, ONLY: PAR_CREATE_NAME
   USE :: IFS_PAR_MOD, ONLY: PAR_ROPEN
   USE :: IFS_PAR_MOD, ONLY: PAR_READ
   USE :: IFS_PAR_MOD, ONLY: PAR_CLOSE
+
+  USE :: IFS_PAR_SERIALIZATION_MOD, ONLY: PAR_SERIALIZE
+  USE :: IFS_PAR_SERIALIZATION_MOD, ONLY: PAR_DESERIALIZE
+
   USE :: IFS_VAL_MOD, ONLY: VAL_CREATE_NAME
   USE :: IFS_VAL_MOD, ONLY: VAL_ROPEN
   USE :: IFS_VAL_MOD, ONLY: VAL_READ_SP
@@ -51,16 +83,7 @@ MODULE MULTIOM_API
   USE :: IFS_VAL_MOD, ONLY: VAL_READ_DP
   USE :: IFS_VAL_MOD, ONLY: VAL_GENERATE_DP
   USE :: IFS_VAL_MOD, ONLY: VAL_CLOSE
-  USE :: IFS_TOC_MOD, ONLY: TOC_CONTAINER_T
-  USE :: IFS_TOC_MOD, ONLY: TOC_CREATE_NAME
-  USE :: IFS_TOC_MOD, ONLY: TOC_ENTRY_BASE_T
-  USE :: IFS_TOC_MOD, ONLY: TOC_SIM_INIT_T
-  USE :: IFS_TOC_MOD, ONLY: TOC_ATM_FIELD_T
-  USE :: IFS_TOC_MOD, ONLY: TOC_WAM_FIELD_T
-  USE :: IFS_TOC_MOD, ONLY: TOC_FLUSH_STEP_T
-  USE :: IFS_TOC_MOD, ONLY: TOC_FLUSH_STEP_RST_T
-  USE :: IFS_TOC_MOD, ONLY: TOC_FLUSH_LAST_STEP_T
-  USE :: IFS_TOC_MOD, ONLY: TOC_SIM_END_T
+
   USE :: IFS_TOC_MOD, ONLY: TOC_READ_ALL
   USE :: IFS_TOC_MOD, ONLY: TOC_READ
   USE :: IFS_TOC_MOD, ONLY: TOC_FREE
@@ -70,6 +93,11 @@ MODULE MULTIOM_API
   USE :: OUTPUT_MANAGER_FACTORY_MOD, ONLY: MAKE_OUTPUT_MANAGER
   USE :: OUTPUT_MANAGER_FACTORY_MOD, ONLY: DESTROY_OUTPUT_MANAGER
 
+  ! General utils
+  USE :: GENERAL_UTILS_MOD, ONLY: READ_TYPE_FROM_ENV
+  USE :: GENERAL_UTILS_MOD, ONLY: READ_YAML_FROM_ENV
+  USE :: GENERAL_UTILS_MOD, ONLY: NEED_FIT_SPECTRUM
+
 IMPLICIT NONE
 
 ! Default visibility