Release notes from pythonnet

v3.1.0

2026-05-23T20:35:17Z

What's Changed

ci: properly exclude job by @RobPasMue in #2542
__delitem__ for IList<T> and IDictionary<K,V> by @lostmsu in #2533
Fix docs workflow by @filmor in #2584
Drop EOLd Python versions by @filmor in #2632
Bump setuptools and adjust license information by @filmor in #2633
Minimal .NET 8 usage changes by @filmor in #2634
Drop performance tests by @filmor in #2636
Properly detect availability of BinaryFormatter by @filmor in #2639
Use last compiler toolset version that support .NET 8 by @filmor in #2640
Add dependabot file by @filmor in #2642
Use official ARM runners by @filmor in #2641
Bump actions/upload-pages-artifact from 3 to 4 by @dependabot[bot] in #2644
Bump actions/setup-python from 2 to 6 by @dependabot[bot] in #2646
Bump actions/checkout from 2 to 5 by @dependabot[bot] in #2648
Bump actions/setup-dotnet from 1 to 5 by @dependabot[bot] in #2645
Use uv and derive as much as possible from the environment, if available by @filmor in #2652
Fixes for the uv CI by @filmor in #2654
Bump astral-sh/setup-uv from 6 to 7 by @dependabot[bot] in #2656
Bump actions/checkout from 5 to 6 by @dependabot[bot] in #2663
Ensure that the tests work even if BinaryFormatter is not available by @filmor in #2638
Bump NUnit3TestAdapter from 5.2.0 to 6.0.0 by @dependabot[bot] in #2667
Fix line endings by @filmor in #2668
Switch to .NET SDK 10 by @lostmsu in #2684
Python 3.14 by @filmor in #2611
CI Improvements by @filmor in #2669
Bump System.Reflection.Emit from 4.3.0 to 4.7.0 by @dependabot[bot] in #2694
Bump pytest from 9.0.2 to 9.0.3 in the uv group across 1 directory by @dependabot[bot] in #2705
CI Improvements by @filmor in #2707
Fix method memleak test by @filmor in #2708
Bump actions/upload-pages-artifact from 4 to 5 by @dependabot[bot] in #2709
Update furo requirement from >=2022.9.15 to >=2025.12.19 by @dependabot[bot] in #2711
Move documentation deps to pyproject.toml by @filmor in #2714
Support .NET Framework 4.6.1 by @Metadorius in #2701
Fix wheel tags by @filmor in #2716
Name missing from all on re-import by @filmor in #2717
Add context manager protocol for .NET IDisposable types by @den-run-ai in #2568
Fix MethodBinding/OverloadMapper memory leak (#691) by @greateggsgreg in #2719
Bump urllib3 from 2.6.3 to 2.7.0 in the uv group across 1 directory by @dependabot[bot] in #2723
Update NUnit by @filmor in #2724
Silence compile-time warnings by @filmor in #2725
Implement support for DLR get/set by @filmor in #2706
Bump idna from 3.13 to 3.15 in the uv group across 1 directory by @dependabot[bot] in #2726

New Contributors

@RobPasMue made their first contribution in #2542
@dependabot[bot] made their first contribution in #2644
@Metadorius made their first contribution in #2701

Full Changelog: v3.0.5...v3.1.0

v3.1.0-rc1

2026-05-16T18:51:21Z

What's Changed

CI Improvements by @filmor in #2669
Bump System.Reflection.Emit from 4.3.0 to 4.7.0 by @dependabot[bot] in #2694
Bump pytest from 9.0.2 to 9.0.3 in the uv group across 1 directory by @dependabot[bot] in #2705
CI Improvements by @filmor in #2707
Fix method memleak test by @filmor in #2708
Bump actions/upload-pages-artifact from 4 to 5 by @dependabot[bot] in #2709
Update furo requirement from >=2022.9.15 to >=2025.12.19 by @dependabot[bot] in #2711
Move documentation deps to pyproject.toml by @filmor in #2714
Support .NET Framework 4.6.1 by @Metadorius in #2701
Fix wheel tags by @filmor in #2716
Name missing from all on re-import by @filmor in #2717
Add context manager protocol for .NET IDisposable types by @den-run-ai in #2568
Fix MethodBinding/OverloadMapper memory leak (#691) by @greateggsgreg in #2719
Bump urllib3 from 2.6.3 to 2.7.0 in the uv group across 1 directory by @dependabot[bot] in #2723
Update NUnit by @filmor in #2724
Silence compile-time warnings by @filmor in #2725
Implement support for DLR get/set by @filmor in #2706

New Contributors

@Metadorius made their first contribution in #2701

Full Changelog: v3.1.0-rc0...v3.1.0-rc1

v3.1.0-rc0

2026-02-25T10:58:46Z

What's Changed

ci: properly exclude job by @RobPasMue in #2542
__delitem__ for IList<T> and IDictionary<K,V> by @lostmsu in #2533
Fix docs workflow by @filmor in #2584
Drop EOLd Python versions by @filmor in #2632
Bump setuptools and adjust license information by @filmor in #2633
Minimal .NET 8 usage changes by @filmor in #2634
Drop performance tests by @filmor in #2636
Properly detect availability of BinaryFormatter by @filmor in #2639
Use last compiler toolset version that support .NET 8 by @filmor in #2640
Add dependabot file by @filmor in #2642
Use official ARM runners by @filmor in #2641
Use uv and derive as much as possible from the environment, if available by @filmor in #2652
Fixes for the uv CI by @filmor in #2654
Ensure that the tests work even if BinaryFormatter is not available by @filmor in #2638
Fix line endings by @filmor in #2668
Switch to .NET SDK 10 by @lostmsu in #2684
Python 3.14 by @filmor in #2611

New Contributors

@RobPasMue made their first contribution in #2542
@dependabot[bot] made their first contribution in #2644

Full Changelog: v3.0.5...v3.1.0-rc0

v3.0.5

2024-12-13T08:39:45Z

What's Changed

Drop console application by @filmor in #2456
Drop reference to Py_Main by @filmor in #2504
Python 3.13 by @filmor in #2454, special thanks to @kunom for the debugging work!

Full Changelog: v3.0.4...v3.0.5

v3.0.4

2024-09-19T17:31:56Z

What's Changed

Allow setting of the python module file by @bmello4688 in #2044
When IterableWrapper iterates up to the middle of list, System.AccessViolationException occurs. by @JakeJP in #2280
#2240 Recursion error when doing reversed python operations on C# types by @gertdreyer in #2327
Added ToPythonAs<T>() by @lostmsu in #2330
IComparable and IEquatable implementations by @lostmsu in #2322
Fix CI by using macos-13 explicitly, adjust OS config by @filmor in #2373
Use non-BOM encodings by @filmor in #2370
Expose serialization api by @BadSingleton in #2336
Handle bad paths in sys.path by @lostmsu in #2383
Simplify UTF8 StrPtr usage by @filmor in #2374
Fix crash when event does not have Add method and improve message for some other internal errors by @lostmsu in #2409
Fix access violation exception on shutdown by @Frawak in #2386

New Contributors

@bmello4688 made their first contribution in #2044
@JakeJP made their first contribution in #2280
@gertdreyer made their first contribution in #2327
@Frawak made their first contribution in #2386

Full Changelog: v3.0.3...v3.0.4

v3.0.3

2023-10-11T07:21:36Z

What's Changed

change PyScope to PyModule by @OmkarBorhade98 in #2231
use enum name in repr by @koubaa in #2239
ARM CI fix by @lostmsu in #2256
Python 3.12 by @filmor in #2249
Only run docs CI/main CI for corresponding changes by @lostmsu in #2257
Revert "Only run docs CI/main CI for corresponding changes" by @filmor in #2260

New Contributors

@OmkarBorhade98 made their first contribution in #2231

Full Changelog: v3.0.2...v3.0.3

v3.0.2

2023-08-29T15:30:47Z

What's Changed

1776 Generic Virtual Method Causes Invalid Program: Fix + test by @rmadsen-ks in #2026
Workaround for Ubuntu-provided package version being unsupported by @lostmsu in #2081
Ensure that load only runs once by @filmor in #2079
Remove suggestions to use internal functions by @filmor in #2092
1783 Implement Interface And Inherit Class by @rmadsen-ks in #2028
Fix GetBuffer throwing ArgumentOutOfRangeException by @legomanww in #2120

New Contributors

@legomanww made their first contribution in #2120

Full Changelog: v3.0.1...v3.0.2

v3.0.1

2022-11-02T23:28:48Z

What's Changed

Implemented dynamic equality and inequality for PyObject instances by @lostmsu in #1849
Got rid of a few deprecation warnings that pollute GitHub code review by @lostmsu in #1850
docs: Fix a few typos by @timgates42 in #1879
Merge release branch back into master by @filmor in #1866
Delete target object from event handler collections when it has no more event handlers by @lostmsu in #1973
Allow decoders to decode Python types derived from primitives by @lostmsu in #1986
Fix positive PyInt converted to negative BigInteger by @lostmsu in #1993
Python 3.11 by @filmor in #1955
Fix implementing a generic interface with a Python class by @filmor in #1998

Full Changelog: v3.0.0...v3.0.1

Release 3.0.0

2022-09-29T15:16:17Z

What's Changed

Increase ob's ref count in tp_repr to avoid accidental free by @DanBarzilian in #1160
fixed crash due to a decref of a borrowed reference in params array handling by @lostmsu in #1163
Drop Python 2 support by @filmor in #1158
remove remoting block for .NET standard by @koubaa in #1170
Pybuffer by @koubaa in #1195
Fix appveyor would only test the PyPI package by @amos402 in #1200
Remove unnecessary CheckExceptionOccurred calls by @amos402 in #1175
Provide more info about failuers to load CLR assemblies by @lostmsu in #1076
Add syntax highlighting to Python code examples in README.rst [docs] by @SFM61319 in #1208
Remove non-existent PInvoke functions by @amos402 in #1205
Bad params object[] precedence (master) by @lostmsu in #1224
drop 3.4 and 3.5 by @koubaa in #1227
really remove old versions by @koubaa in #1230
Added a test for finalization on shutdown by @lostmsu in #1206
fix compiler warning by @koubaa in #1226
Ensure only implementers of IEnumerable or IEnumerator are considered Iterable by @danabr in #1241
Select correct method to invoke when keyword arguments are used by @danabr in #1242
Wrap returned objects in interface if method return type is interface by @danabr in #1240
Non-delegate types should not be callable by @alxnull in #1247
Make indexers work for interface objects by @danabr in #1246
Make it possible to use inherited indexers by @danabr in #1248
Add soft shutdown by @amos402 in #958
Fixed dllLocal not being initialized. by @benoithudson in #1252
Return interface objects when iterating over interface collections by @danabr in #1257
Make len work for ICollection<> interface objects by @danabr in #1253
Enable Source Link and symbol package generation during build by @lostmsu in #1259
Fixed polyfill for TypeBuilder.CreateType by @lostmsu in #1261
fix wrongly cased Microsoft.CSHARP.Targets by @vivainio in #1271
Intern string by @amos402 in #1254
Use .NET Core 3.1 LTS for tests (instead of 2.0) by @lostmsu in #1279
Python 3.9 by @filmor in #1264
Remove deprecated implicit assembly loading by @lostmsu in #1277
Ensure methods of Object are also available on interface objects by @danabr in #1284
Fix kwarg func resolution by @jmlidbetter in #1136
Allow creating new .NET arrays from Python using Array[T](dim1, dim2,…) syntax by @lostmsu in #1291
Detect the size of wchar_t (aka Runtime.UCS) at runtime using PyUnicode_GetMax by @lostmsu in #1298
TypeOffset class no longer depends on target Python version by @lostmsu in #1292
[Out] parameters no longer added to return tuple by @lostmsu in #1308
Added github actions workflow to replace travis by @lostmsu in #1307
Convert projects to SDK style by @filmor in #1209
Test other Operating Systems than Linux via Github Actions by @filmor in #1310
Ensure that param-array matching works correctly by @filmor in #1304
Remove API warnings as these will be stabilised for 3.0 by @filmor in #1315
Replace custom platform handling by RuntimeInformation by @filmor in #1314
Fixed CollectBasicObject test by @lostmsu in #1313
Implement inplace building and develop by @filmor in #1317
Drop the long-deprecated CLR.* alias by @filmor in #1319
Fix or disable warnings in Python.Runtime by @filmor in #1318
Fixed segfault in ClassDerived.tp_dealloc by @lostmsu in #1330
Fixed crash in finalizer of CLR types defined in Python, that survive engine shutdown by @lostmsu in #1260
Test for non-ASCII encoded method name by @filmor in #1329
Fix illegal delegate usage by @BadSingleton in #1328
PyIter: do not force dispose previous object upon moving to the next one by @lostmsu in #1331
Incorrectly using a non-generic type with type parameters now produces a helpful Python error instead of throwing NullReferenceException by @tminka in #1326
Call PyErr_NormalizeException for exceptions by @slide in #1265
TestPythonEngineProperties.SetPythonPath avoids corrupting the module search path for later tests by @tminka in #1336
ABI.Initialize gives a helpful message when the TypeOffset interop class is not configured correctly by @tminka in #1340
Better error messages from PyObject.AsManagedObject and DelegateManager.TrueDispatch by @tminka in #1344
Python tests can now be debugged by running them as embedded tests within NUnit by @tminka in #1341
Operator overloads support by @christabella in #1324
Domain reload test cases fixes by @BadSingleton in #1287
Add more more tests for in, out and ref parameters by @BadSingleton in #1349
Support comparison operators by @christabella in #1347
Disable implicit conversion from PyFloat to .NET integer types by @lostmsu in #1343
Add GetPythonThreadID and Interrupt methods in PythonEngine by @gpetrou in #1337
Disable implicit conversion from PyFloat to uint64 by @tminka in #1362
Disable implicit conversion from float to array index by @tminka in #1363
Better error messages for method argument mismatch and others by @tminka in #1361
Support ByRef arguments in event handlers by @tminka in #1364
Build single Python.Runtime.dll for all platforms by @lostmsu in #1365
Fix exception string by @filmor in #1360
ParameterInfo.Name needs to be checked for null before usage by @filmor in #1375
Monthly NuGet release previews by @lostmsu in #1381
Sign Runtime DLL with a strong name by @gpetrou in #1382
New loading based on clr_loader by @filmor in #1373
Simplify PyScope by delegating ownership to PyObject instance by @lostmsu in #1367
implement list codec by @koubaa in #1084
Ensure interned strings can not be referenced after InternString.Shutdown by @lostmsu in #1394
Made InterruptTest more robust by @lostmsu in #1393
Adjust static libpython detection by @filmor in #1396
Remove Utf8Marshaler, set PyScope base class to PyObject, added PyModule by @lostmsu in #1391
ImportHook cleanup + PyObject.Length exception by @lostmsu in #1400
Suggest to set Runtime.PythonDLL when embedding in .NET by @lostmsu in #1411
Allow GIL state debugging; require GILState to be properly disposed by @lostmsu in #1397
Try libdl.so.2 on Linux before libdl.so by @lostmsu in #1425
PyType class, wrapper for Python types by @lostmsu in #1395
Reworked Enum marshaling by @lostmsu in #1392
Prevent stack overflow when an encoder is registered from Python by @lostmsu in #1429
Do not call find_libpython during import clr as Python.Runtime can find it on its own by @lostmsu in #1440
Fixed __cause__ on overload bind failure and array conversion by @lostmsu in #1442
Replace magic offsets with proper offset calculation by @lostmsu in #1441
Detect Py_TRACE_REFS at runtime and calculate object offsets accordingly by @lostmsu in #1426
Re-enable the domain reload tests by @BadSingleton in #1404
Dispose all temporary objects in PyCheck_Iter_PyObject_IsIterable_ThreadingLock_Test by @lostmsu in #1456
Use PyType instances instead of raw pointers by @lostmsu in #1431
Refactoring of tp_dealloc by @lostmsu in #1459
Refactoring of tp_clear by @lostmsu in #1460
Handle ProcessExit event by @lostmsu in #1458
Improve Python <-> .NET exception integration by @lostmsu in #1134
Add a failing test for Unicode conversion by @pkese in #1467
Modernize import hook by @BadSingleton in #1369
Fixed crash in ToArray when sequence explicitly denies len by @lostmsu in #1484
Prevent crash during debugging when attempting to inspect PyObject by @lostmsu in #1483
Fixed double call to PyType_Ready in CLR MetaType's tp_new by @lostmsu in #1486
Create PyIter from existing PyObject by @lostmsu in #1482
[WIP] Add ability to create module from C# by @slide in #1447
Fixed custom decoders not working for DateTime and Decimal by @lostmsu in #1497
Allow substituting base types for CLR types (as seen from Python) by @lostmsu in #1487
Property descriptor made visible on the reflected class by @lostmsu in #1512
Validate, that custom Python base types can be inherited from by @lostmsu in #1510
Names of .NET types changed to better support generic types by @lostmsu in #1509
Dynamic arithmetic ops raise correct Python exception on failure by @lostmsu in #1508
Py.Import and PyModule.Import return PyObject instead of PyModule by @lostmsu in #1530
Remove needsResolution hack by @lostmsu in #1531
Implements buffer interface for .NET arrays of primitive types by @lostmsu in #1511
Call tp_clear of base unmanaged type by @lostmsu in #1541
Allow decoders affect PyObject.As<object>() by @lostmsu in #1546
Added workaround for warning in threading module after TestInterrupt by @lostmsu in #1560
ClassManager illegally decrefed ClassObject's refcount on shutdown by @lostmsu in #1563
Ensure tests, that need running PythonEngine have similar SetUp and TearDown by @lostmsu in #1564
Allow decoding instanceless exceptions by @lostmsu in #1544
Do not clean tpHandle in ClassBase.tp_clear - it might be used in tp_dealloc by @lostmsu in #1566
Mixins for standard collections that implement collections.abc interfaces by @lostmsu in #1543
Allow Python to overwrite .NET methods by @lostmsu in #1545
Simplify Dispatcher by @lostmsu in #1559
Simplify assembly ResolveHandler, and use official assembly name parsing by @lostmsu in #1570
Disable implicit conversions that might lose information by @lostmsu in #1568
Minor fixup for no autoconversions PR by @lostmsu in #1574
Fixed FileLoadException when trying clr.AddReference('/full/path.dll') by @lostmsu in #1573
Raise BadPythonDllException instead of confusing TypeLoadException when PythonDLL was not configured properly by @lostmsu in #1577
Cleaning up public API by @lostmsu in #1557
PyScope/PyModule API cleanup by @lostmsu in #1569
name and signature for .NET methods by @lostmsu in #1133
When reflecting nested types, ensure their corresponding PyType is allocated by @lostmsu in #1579
Safer GetAttr(name, default) by @lostmsu in #1578
Expose PyType.Get by @lostmsu in #1581
Allow user-created instances of PySequence and PyIterable by @lostmsu in #1580
Changed signature of IPyObjectDecoder.CanDecode by @lostmsu in #1583
Disabled float and bool implicit conversions by @lostmsu in #1584
Remove a deprecated attribute in PropertyObject by @BadSingleton in #1595
Python 3.10 by @filmor in #1591
Make .NET objects that have __call__ method callable from Python by @lostmsu in #1589
Fixed recursive dependency in clr module initialization by @lostmsu in #1602
Include README.md into NuGet package by @lostmsu in #1599
Remove unused PythonMethodAttribute by @lostmsu in #1609
Track Runtime run number by @lostmsu in #1074
Use .NET 6.0 LTS and C# 10 by @lostmsu in #1620
Update NonCopyableAnalyzer to latest version with our changes upstreamed by @lostmsu in #1624
Use new references by @lostmsu in #1603
Fixed all warnings except explicit ones by @lostmsu in #1635
Match generic and private methods upon runtime reload by @lostmsu in #1637
Require newest available clr-loader by @filmor in #1643
Fix the PyGILState_STATE type by @filmor in #1645
Fix warning regarding undefined module on GC Offset Base by @filmor in #1646
Removed ShutdownMode. Now always behaves like original Reload by @lostmsu in #1638
When process is exiting, there's no need to save live .NET objects by @lostmsu in #1648
Moved Py class into its own file by @lostmsu in #1649
Added a regression test for calling base method from nested class by @lostmsu in #1652
Fixed accessing partially overriden properties from Python by @lostmsu in #1650
Reworked the way .NET objects are constructed from Python by @lostmsu in #1651
Improved support for generic method overloading by @lostmsu in #1657
Use Delegates to access Py_NoSiteFlag by @lostmsu in #1659
Provide __int__ instance method on enum types to support int(Enum.Member) by @lostmsu in #1661
Cleanup PyBuffer a bit by @lostmsu in #1662
Support for byref parameters when overriding .NET methods from Python by @lostmsu in #1663
Performance tests with baseline from Pypi by @filmor in #1667
Move code to subdirectories and rename or split up by @filmor in #1665
Added ARM64 CI action by @lostmsu in #1669
Only run CI on pushes to master and on all pull requests by @filmor in #1670
Temporary fix method binder for out parameters by @eirannejad in #1672
Added todo note to ensure CLA is signed by @eirannejad in #1674
Add tests for exception leaking. by @BadSingleton in #1679
We can drop the import hack as we are now using the newer import mechanics by @filmor in #1686
Update CHANGELOG.md by @nobbi1991 in #1690
Allow dynamic PyObject conversion to IEnumerable by @lostmsu in #1697
add GitHub URL for PyPi by @andriyor in #1708
Make methods of PyObject inherited from its base .NET classes GIL-safe by @lostmsu in #1711
Support for BigInteger (C#) <-> PyInt by @lostmsu in #1710
On shutdown from Python release all slot holders by @lostmsu in #1712
Clear weakref list when reflected object is destroyed by @lostmsu in #1758
Clear weak reference list when an extension type is destroyed by @lostmsu in #1761
Fix layout of NativeTypeSpec on 32 bit platforms by @lostmsu in #1765
Implement IConvertible on PyObject by @filmor in #1762
Ensure that codec tests are run by @filmor in #1763
Fix decimal default parameters by @filmor in #1773
Work around potential Mono bug, that hangs the runtime when new threads start by @lostmsu in #1779
Miscellaneous fixes and cleanups by @filmor in #1760
Fix enum codec by @filmor in #1621
Disallow runtime shutdown when the Python error indicator is set by @lostmsu in #1780
Multiple fixes related to Dictionary.Keys bug by @lostmsu in #1786
Drop Python 3.6 support by @filmor in #1795
Move to modern setuptools with pyproject.toml by @filmor in #1793
Min/MaxSupportedVersion and IsSupportedVersion on PythonEngine by @filmor in #1799
Min/MaxSupportedVersion and IsSupportedVersion on PythonEngine by @lostmsu in #1798
Add explicit tests for vararg call by @filmor in #1805
Fix demo scripts by @filmor in #1802
fixed ForbidPythonThreadsAttribute being ignored in certain scenarios by @filmor in #1815
Add test for enum int conversion by @filmor in #1811
Implement configuring clr from environment by @filmor in #1817
Take GIL when checking if error occurred on shutdown by @filmor in #1836
Fix (U)IntPtr construction by @filmor in #1861
Fix string construction by @filmor in #1862
Fix docstring for directly constructed types by @filmor in #1865
Fixed a leak in NewReference.Move by @lostmsu in #1873
Add XML docs to NuGet by @lostmsu in #1878
Mention the need for Initialize and BeginAllowThreads in the README by @lostmsu in #1897
Disabled implicit seq to array conversion by @lostmsu in #1902
Explicit float and int conversion for builtin types by @filmor in #1904
Fill nb_index slot for integer types by @filmor in #1907
Fixed use of the process handle after Process instance is garbage collected by @lostmsu in #1940
Fixed new line character at the end of informational version by @lostmsu in #1941
Enabled test for NoStackOverflowOnSystemType by @lostmsu in #1943
Config-less CoreCLR and improved runtime load message by @filmor in #1942
Implicit float conversion in function calls by @filmor in #1908
Documentation by @filmor in #1863

New Contributors

@DanBarzilian made their first contribution in #1160
@SFM61319 made their first contribution in #1208
@danabr made their first contribution in #1241
@alxnull made their first contribution in #1247
@BadSingleton made their first contribution in #1328
@tminka made their first contribution in #1326
@christabella made their first contribution in #1324
@gpetrou made their first contribution in #1337
@pkese made their first contribution in #1467
@eirannejad made their first contribution in #1672
@nobbi1991 made their first contribution in #1690
@andriyor made their first contribution in #1708

Full Changelog: v2.5.2...v3.0.0

v3.0.0-r1

2022-09-29T22:13:50Z

Release 3.0.0-r1