Add 3.13 build, remove 3.8 and update numpy to v2

.github/workflows/build.yml

@@ -22,7 +22,7 @@ jobs:
     strategy:
       fail-fast: False
       matrix:
-        python-version: [ '3.8', '3.9', '3.10', '3.11', '3.12' ]
+        python-version: [ '3.9', '3.10', '3.11', '3.12', '3.13' ]
     steps:
       - name: Checkout repository
         uses: actions/checkout@v4
@@ -66,8 +66,8 @@ jobs:
 
       - name: Build wheels
         env:
-          # only build CPython-3.8+ and skip 32-bit builds
-          CIBW_BUILD: cp38-* cp39-* cp310-* cp311-* cp312-*
+          # only build CPython-3.9+ and skip 32-bit builds
+          CIBW_BUILD: cp39-* cp310-* cp311-* cp312-* cp313-*
           CIBW_SKIP: "*-manylinux_i686 *-musllinux*"
           # use latest build
           CIBW_MANYLINUX_X86_64_IMAGE: quay.io/pypa/manylinux2014_x86_64
@@ -91,7 +91,7 @@ jobs:
     strategy:
       matrix:
         os: [ windows-latest, ubuntu-latest, macos-latest ]
-        python-version: [ '3.8', '3.9', '3.10', '3.11', '3.12' ]
+        python-version: [ '3.9', '3.10', '3.11', '3.12', '3.13' ]
 
     steps:
       - name: Checkout repository

setup.cfg

@@ -26,11 +26,11 @@ classifiers =
     Operating System :: Microsoft :: Windows
     Operating System :: Unix
     Programming Language :: C++
-    Programming Language :: Python :: 3.6
-    Programming Language :: Python :: 3.7
-    Programming Language :: Python :: 3.8
     Programming Language :: Python :: 3.9
     Programming Language :: Python :: 3.10
+    Programming Language :: Python :: 3.11
+    Programming Language :: Python :: 3.12
+    Programming Language :: Python :: 3.13
     Topic :: Scientific/Engineering
 
 [options]

setup.py

@@ -19,7 +19,9 @@
 
 setup(
     version=version,
-    install_requires=["numpy >=1.18.5"],
+    python_requires=">=3.9",
+    install_requires=["numpy >=2,<3"],
+    setup_requires=["numpy >=2,<3"],
     ext_modules=[NLOptBuildExtension("nlopt._nlopt", version)],
     cmdclass={"build_ext": NLOptBuild},
     zip_safe=False,