diff --git a/.travis.yml b/.travis.yml
index 81e8318ec..c8db3c5dc 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -555,6 +555,7 @@ script:
             python testdata/pymod/import_db.py;
             python testdata/pymod/import_rdb.py;
             python testdata/pymod/import_tl.py;
+            python testdata/pymod/import_lib.py;
             python testdata/pymod/pya_tests.py;
         fi
     fi 
@@ -565,6 +566,7 @@ script:
         python testdata/pymod/import_db.py;
         python testdata/pymod/import_rdb.py;
         python testdata/pymod/import_tl.py;
+        python testdata/pymod/import_lib.py;
         python testdata/pymod/pya_tests.py;
         klayout_version=$(python -c 'import setup; print(setup.Config().version())');
         mkdir -p deploy/dist-pymod/$klayout_version;
diff --git a/azure-pipelines.yml b/azure-pipelines.yml
index 28804a941..08804ca66 100644
--- a/azure-pipelines.yml
+++ b/azure-pipelines.yml
@@ -84,6 +84,7 @@ jobs:
       python testdata/pymod/import_db.py
       python testdata/pymod/import_rdb.py
       python testdata/pymod/import_tl.py
+      python testdata/pymod/import_lib.py
       python testdata/pymod/pya_tests.py
     displayName: 'Test KLayout pymod'
 
diff --git a/setup.py b/setup.py
index df9715931..3faaa0b7f 100644
--- a/setup.py
+++ b/setup.py
@@ -407,8 +407,8 @@ _lib_sources = set(glob.glob(os.path.join(_lib_path, "*.cc")))
 
 _lib = Library(config.root + '._lib',
               define_macros=config.macros() + [('MAKE_LIB_LIBRARY', 1)],
-              include_dirs=[_tl_path, _db_path, _lib_path],
-              extra_objects=[config.path_of('_tl', _tl_path), config.path_of('_db', _db_path)],
+              include_dirs=[_tl_path, _gsi_path, _db_path, _lib_path],
+              extra_objects=[config.path_of('_tl', _tl_path), config.path_of('_gsi', _gsi_path), config.path_of('_db', _db_path)],
               language='c++',
               extra_link_args=config.link_args('_lib'),
               extra_compile_args=config.compile_args('_lib'),
@@ -492,8 +492,8 @@ lib_sources = set(glob.glob(os.path.join(lib_path, "*.cc")))
 
 lib = Extension(config.root + '.libcore',
                define_macros=config.macros(),
-               include_dirs=[_lib_path, _tl_path, _db_path],
-               extra_objects=[config.path_of('_lib', _lib_path), config.path_of('_tl', _tl_path), config.path_of('_db', _db_path)],
+               include_dirs=[_lib_path, _tl_path, _gsi_path, _pya_path],
+               extra_objects=[config.path_of('_lib', _lib_path), config.path_of('_tl', _tl_path), config.path_of('_gsi', _gsi_path), config.path_of('_pya', _pya_path)],
                extra_link_args=config.link_args('libcore'),
                sources=list(lib_sources))
 
@@ -506,7 +506,7 @@ rdb_sources = set(glob.glob(os.path.join(rdb_path, "*.cc")))
 rdb = Extension(config.root + '.rdbcore',
                 define_macros=config.macros(),
 
-                include_dirs=[_rdb_path, _db_path, _tl_path, _gsi_path, _pya_path],
+                include_dirs=[_rdb_path, _tl_path, _gsi_path, _pya_path],
                 extra_objects=[config.path_of('_rdb', _rdb_path), config.path_of('_tl', _tl_path), config.path_of('_gsi', _gsi_path), config.path_of('_pya', _pya_path)],
                 extra_link_args=config.link_args('rdbcore'),
                 sources=list(rdb_sources))