diff --git a/pyresample/_spatial_mp.py b/pyresample/_spatial_mp.py
index 7cb45b4d..20846ee2 100644
--- a/pyresample/_spatial_mp.py
+++ b/pyresample/_spatial_mp.py
@@ -188,7 +188,7 @@ def _run_jobs(target, args, nprocs):
         p.join()
     if ierr.value != 0:
         raise RuntimeError('%d errors in worker processes. Last one reported:\n%s' %
-                           (ierr.value, warn_msg.value._object_hook()))
+                           (ierr.value, warn_msg.value))
 
 # This is executed in an external process:
 
diff --git a/setup.py b/setup.py
index 1c001460..5f65acca 100644
--- a/setup.py
+++ b/setup.py
@@ -25,7 +25,7 @@
 import versioneer
 
 requirements = ['pyproj>=3.0', 'configobj',
-                'pykdtree>=1.3.1', 'pyyaml', 'numpy>=1.21.0',
+                'pykdtree>=1.3.1', 'pyyaml', 'numpy>=1.25.0',
                 "shapely", "donfig", "platformdirs",
                 ]
 
@@ -55,8 +55,8 @@
     Extension("pyresample.ewa._ll2cr", sources=["pyresample/ewa/_ll2cr.pyx"],
               include_dirs=[np.get_include()],
               extra_compile_args=extra_compile_args,
-              cython_directives={"language_level": 3},
-              define_macros=[("NPY_NO_DEPRECATED_API", "NPY_1_7_API_VERSION")],
+              cython_directives={"language_level": 3, "freethreading_compatible": True},
+              define_macros=[("NPY_NO_DEPRECATED_API", "NPY_1_25_API_VERSION")],
               ),
     Extension("pyresample.ewa._fornav",
               sources=["pyresample/ewa/_fornav.pyx",
@@ -64,15 +64,15 @@
               include_dirs=[np.get_include()],
               language="c++", extra_compile_args=extra_compile_args,
               depends=["pyresample/ewa/_fornav_templates.h"],
-              cython_directives={"language_level": 3},
-              define_macros=[("NPY_NO_DEPRECATED_API", "NPY_1_7_API_VERSION")],
+              cython_directives={"language_level": 3, "freethreading_compatible": True},
+              define_macros=[("NPY_NO_DEPRECATED_API", "NPY_1_25_API_VERSION")],
               ),
     Extension("pyresample.gradient._gradient_search",
               sources=["pyresample/gradient/_gradient_search.pyx"],
               include_dirs=[np.get_include()],
               extra_compile_args=extra_compile_args,
-              cython_directives={"language_level": 3},
-              define_macros=[("NPY_NO_DEPRECATED_API", "NPY_1_7_API_VERSION")],
+              cython_directives={"language_level": 3, "freethreading_compatible": True},
+              define_macros=[("NPY_NO_DEPRECATED_API", "NPY_1_25_API_VERSION")],
               ),
 ]
 
@@ -106,13 +106,15 @@
           ext_modules=extensions,
           entry_points=entry_points,
           zip_safe=False,
+          license="LGPL-3.0-or-later",
+          license_files=["LICENSE.txt"],
           classifiers=[
               'Development Status :: 5 - Production/Stable',
-              'License :: OSI Approved :: GNU Lesser General Public License v3 or later (LGPLv3+)',
               'Programming Language :: Python',
               'Programming Language :: Cython',
               'Operating System :: OS Independent',
               'Intended Audience :: Science/Research',
-              'Topic :: Scientific/Engineering'
+              'Topic :: Scientific/Engineering',
+              'Programming Language :: Python :: Free Threading :: 1 - Unstable',
           ]
           )