Add support for freethreading in extension

.github/workflows/test-libmaxminddb.yml

@@ -13,7 +13,7 @@ jobs:
 
     strategy:
       matrix:
-        env: [3.9, "3.10", 3.11, 3.12, 3.13, 3.14]
+        env: ["3.10", 3.11, 3.12, 3.13, 3.14]
         # We don't test on Windows currently due to issues
         # build libmaxminddb there.
         os: [ubuntu-latest, ubuntu-24.04-arm, macos-latest]
@@ -56,7 +56,7 @@ jobs:
           echo "LDFLAGS=-L/opt/homebrew/lib" >> "$GITHUB_ENV"
 
       - name: Build with Werror and Wall
-        run: uv build
+        run: uv build --python ${{ matrix.env }}
         env:
           CFLAGS: "${{ env.CFLAGS }} -Werror -Wall -Wextra"
 

.github/workflows/test.yml

@@ -15,7 +15,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        env: [3.9, "3.10", 3.11, 3.12, 3.13, 3.14]
+        env: ["3.10", 3.11, 3.12, 3.13, 3.14]
         os: [ubuntu-latest, ubuntu-24.04-arm, macos-latest, windows-latest]
     steps:
       - uses: actions/checkout@v5
@@ -32,6 +32,7 @@ jobs:
       - name: Setup test suite
         run: tox run -vv --notest --skip-missing-interpreters false
         env:
+          MAXMINDDB_REQUIRE_EXTENSION: 1
           TOX_GH_MAJOR_MINOR: ${{ matrix.env }}
       - name: Run test suite
         run: tox run --skip-pkg-install

HISTORY.rst

@@ -6,9 +6,15 @@ History
 2.9.0
 ++++++++++++++++++
 
+* IMPORTANT: Python 3.10 or greater is required. If you are using an older
+  version, please use an earlier release.
 * Databases can now be loaded from buffers. This can be done by passing in a
   buffer as the database and using mode ``MODE_FD``. Pull request by Emanuel
   Seemann. GitHub #234.
+* The C extension now supports Python 3.13+ free-threading mode and is
+  thread-safe for concurrent reads on platforms with pthread support (such as
+  Linux and macOS) and Windows. On other platforms, the extension will use
+  GIL-based protection.
 
 2.8.2 (2025-07-25)
 ++++++++++++++++++

README.rst

@@ -94,10 +94,20 @@ The module will return an ``InvalidDatabaseError`` if the database is corrupt
 or otherwise invalid. A ``ValueError`` will be thrown if you look up an
 invalid IP address or an IPv6 address in an IPv4 database.
 
+Thread Safety
+-------------
+
+Both the C extension and pure Python implementations are safe for concurrent
+reads and support Python 3.13+ free-threading. The C extension provides
+free-threading support on platforms with pthread support (such as Linux and
+macOS) and Windows. On other platforms, the extension will use GIL-based
+protection. Calling ``close()`` while reads are in progress may cause
+exceptions in those threads.
+
 Requirements
 ------------
 
-This code requires Python 3.9+. Older versions are not supported. The C
+This code requires Python 3.10+. Older versions are not supported. The C
 extension requires CPython.
 
 Versioning