diff --git a/.github/workflows/sdist.yml b/.github/workflows/sdist.yml
new file mode 100644
index 0000000..a938ff9
--- /dev/null
+++ b/.github/workflows/sdist.yml
@@ -0,0 +1,35 @@
+# This workflow will install Python and build sdist
+
+name: sdist
+
+on:
+  workflow_dispatch:
+  pull_request:
+  push:
+    branches:
+      - master
+      - dev
+
+jobs:
+  build-dist:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v4
+      with:
+        persist-credentials: false
+
+    - name: Set up Python
+      uses: actions/setup-python@v5
+      with:
+        python-version: 3.13
+
+    - name: Build package
+      run: |
+        pip install build
+        # fake IDL_DIR to build source package without installing IDL
+        IDL_DIR=/fake-idl-dir python -m build --sdist .
+
+    - name: Store source distribution as artifact
+      uses: actions/upload-artifact@v4
+      with:
+        path: 'dist/idlbridge-*.tar.gz'
diff --git a/MANIFEST.in b/MANIFEST.in
index 33f21da..603ab84 100644
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -1,3 +1,3 @@
 include README.md MANIFEST.in setup.py .gitignore
-recursive-include idlbridge *.py *.pyx *.pxd *.pxi *.pro VERSION
+recursive-include idlbridge *.py *.pyx *.pxd *.pxi *.pro
 recursive-include dev *
diff --git a/idlbridge/VERSION b/idlbridge/VERSION
deleted file mode 100644
index 1cc5f65..0000000
--- a/idlbridge/VERSION
+++ /dev/null
@@ -1 +0,0 @@
-1.1.0
\ No newline at end of file
diff --git a/idlbridge/__init__.py b/idlbridge/__init__.py
index de451ef..743aca0 100644
--- a/idlbridge/__init__.py
+++ b/idlbridge/__init__.py
@@ -26,9 +26,15 @@
 import ctypes as _ctypes
 from . import _core
 
+try:
+    from importlib.metadata import version
+except ImportError:
+    # try-except be removed if requires-python set to >= 3.8
+    from importlib_metadata import version
+
 __author__ = 'Dr. Alex Meakins'
 __responsible_officer__ = 'Dr. Alex Meakins'
-__version__ = "1.1.0"
+__version__ = version("idlbridge")
 
 # By default the core (IDL) library is opened by Python with RTLD_LOCAL
 # preventing subsequently loaded IDL DLM libraries from seeing the IDL_*
diff --git a/pyproject.toml b/pyproject.toml
new file mode 100644
index 0000000..dcf2909
--- /dev/null
+++ b/pyproject.toml
@@ -0,0 +1,3 @@
+[build-system]
+requires = ["setuptools", "Cython", "numpy"]
+build-backend = "setuptools.build_meta"
diff --git a/setup.py b/setup.py
index eb1fbad..414a3f1 100644
--- a/setup.py
+++ b/setup.py
@@ -15,8 +15,7 @@
 # You should have received a copy of the GNU Lesser General Public License
 # along with IDLBridge. If not, see <http://www.gnu.org/licenses/>.
 
-from distutils.core import setup
-from distutils.extension import Extension
+from setuptools import setup, Extension
 from Cython.Build import cythonize
 import sys
 import numpy
@@ -57,22 +56,18 @@
 extra_compile_args = []
 extra_link_args = ["-Wl,-rpath,.", "-Wl,-rpath,{}".format(idl_library_path)]
 
-setup_path = path.dirname(path.abspath(__file__))
+idl_core_sources = ["idlbridge/_core.pyx"]
+idl_core = Extension(
+    "idlbridge._core",
+    idl_core_sources,
+    include_dirs=include_dirs,
+    libraries=libraries,
+    library_dirs=library_dirs,
+    extra_compile_args=extra_compile_args,
+    extra_link_args=extra_link_args,
+)
 
-# build extension list
-extensions = []
-for root, dirs, files in os.walk(setup_path):
-    for file in files:
-        if path.splitext(file)[1] == ".pyx":
-            pyx_file = path.relpath(path.join(root, file), setup_path)
-            module = path.splitext(pyx_file)[0].replace("/", ".")
-            extensions.append(Extension(module,
-                                        [pyx_file],
-                                        include_dirs=include_dirs,
-                                        libraries=libraries,
-                                        library_dirs=library_dirs,
-                                        extra_compile_args=extra_compile_args,
-                                        extra_link_args=extra_link_args))
+extensions = [idl_core]
 
 if profile:
     directives = {"profile": True}
@@ -83,6 +78,7 @@
     name="idlbridge",
     version=__version__,
     description="An IDL wrapper for Python",
+    requires_python=">=3.4",
     author='Dr. Alex Meakins',
     author_email='alex.meakins@ukaea.uk',
     license="LGPLv3",
@@ -96,8 +92,10 @@
         "Operating System :: POSIX :: Linux",
         "Topic :: Scientific/Engineering"
     ],
-#     setup_requires=["cython>=0.19"],
-#     install_requires=["cython>=0.19"],
+    install_requires=[
+        "importlib_metadata>=0.1 ; python_version < \"3.8\"",
+        "numpy",
+    ],
     packages=["idlbridge"],
     ext_modules=cythonize(extensions, force=force, compiler_directives=directives)
 )