diff --git a/memfs.py b/memfs.py
index fdee6af01..a47bbed21 100755
--- a/memfs.py
+++ b/memfs.py
@@ -39,9 +39,13 @@ except:
     ascii = lambda x: str(x)           # Python 2
 
 
-# The last argument is the path of the generated C file
+# The last argument is the base name of the generated C file(s)
 output_file_path = sys.argv[-1]
-g = open(output_file_path, "w")
+CHUNK = 7 * 1000 * 1000 # chunk size in bytes
+totsize = 0 # amount written
+fcount = 0
+opath = output_file_path + "_" + str(fcount).zfill(3) + ".c"
+g = open(opath, "w")
 
 for directory in dirs:
 
@@ -63,6 +67,7 @@ for directory in dirs:
                 continue
 
             fsize = os.path.getsize(full)
+            totsize += fsize
             full = full.replace("\\","/")
             fname = full[full.find("/%s/" % (dname,)):]
             #print("MEMFS add", fname)
@@ -73,8 +78,7 @@ for directory in dirs:
             FILES[name] = fname
             SIZES[name] = fsize
 
-            print('static const unsigned char %s[] = {' % (name,), file=g)
-            #print('const unsigned char %s[] = {' % (name,), file=g) #NEW
+            print('const unsigned char %s[] = {' % (name,), file=g) #NEW
 
             with open(full, 'rb') as f:
                 i = 0
@@ -94,6 +98,18 @@ for directory in dirs:
                         print("", file=g)
 
             print('};', file=g)
+            if totsize >= CHUNK:
+                g.close()
+                fcount += 1
+                opath = output_file_path + "_" + str(fcount).zfill(3) + ".c"
+                #print('....Now writing to ',opath)
+                g = open(opath, "w")
+                totsize = 0
+
+g.close()
+output_file_path = output_file_path + "_final.c"
+#print('....Finally writing to ',output_file_path)
+g = open(output_file_path, "w")
 
 print("""
 #include "eccodes_config.h"
@@ -108,9 +124,9 @@ print("""
 #include "eccodes_windef.h"
 """, file=g)
 
-# NEW
-#for k, v in SIZES.items():
-#    print ('extern const unsigned char %s[%d];' % (k, v), file=g)
+# Write extern variables with sizes
+for k, v in SIZES.items():
+    print ('extern const unsigned char %s[%d];' % (k, v), file=g)
 
 print("""
 struct entry {
diff --git a/memfs/CMakeLists.txt b/memfs/CMakeLists.txt
index b219298f6..2827da4d5 100644
--- a/memfs/CMakeLists.txt
+++ b/memfs/CMakeLists.txt
@@ -4,18 +4,25 @@ if( NOT HAVE_PRODUCT_BUFR )
 elseif( NOT HAVE_PRODUCT_GRIB )
   set( exclude -exclude grib )
 endif()
+
+set( generated_c_files
+    ${CMAKE_CURRENT_BINARY_DIR}/memfs_gen_000.c
+    ${CMAKE_CURRENT_BINARY_DIR}/memfs_gen_001.c
+    ${CMAKE_CURRENT_BINARY_DIR}/memfs_gen_002.c
+    ${CMAKE_CURRENT_BINARY_DIR}/memfs_gen_final.c)
+
 add_custom_command(
-  OUTPUT  ${CMAKE_CURRENT_BINARY_DIR}/memfs.c
+  OUTPUT ${generated_c_files}
   COMMAND ${PYTHON_EXECUTABLE} ${PROJECT_SOURCE_DIR}/memfs.py
     ${exclude}
     ${PROJECT_SOURCE_DIR}/definitions
     ${PROJECT_SOURCE_DIR}/samples
     ${PROJECT_SOURCE_DIR}/ifs_samples
-    ${CMAKE_CURRENT_BINARY_DIR}/memfs.c
+    ${CMAKE_CURRENT_BINARY_DIR}/memfs_gen
   DEPENDS ${PROJECT_SOURCE_DIR}/memfs.py)
 
 set_source_files_properties(
-    ${CMAKE_CURRENT_BINARY_DIR}/memfs.c PROPERTIES OBJECT_DEPENDS
+    ${generated_c_files} PROPERTIES OBJECT_DEPENDS
     "${PROJECT_SOURCE_DIR}/memfs.py"
     # "${PROJECT_SOURCE_DIR}/memfs.py" ${definition_files}"
     )
@@ -28,6 +35,6 @@ endif()
 
 if( HAVE_MEMFS )
     ecbuild_add_library(TARGET    eccodes_memfs
-                        SOURCES   ${CMAKE_CURRENT_BINARY_DIR}/memfs.c
-                        GENERATED ${CMAKE_CURRENT_BINARY_DIR}/memfs.c)
+                        SOURCES   ${generated_c_files}
+                        GENERATED ${generated_c_files})
 endif()