From e7c4feae8576a34e0bbb0f8515b675e63eab3785 Mon Sep 17 00:00:00 2001
From: DmitriyMusatkin <musatkd@amazon.com>
Date: Wed, 11 Feb 2026 01:14:10 -0800
Subject: [PATCH 01/22] xxhash

---
 awscrt/checksums.py    |  60 +++++++++++
 crt/aws-checksums      |   2 +-
 source/checksums.h     |   9 ++
 source/module.c        |  10 ++
 source/xxhash.c        | 230 +++++++++++++++++++++++++++++++++++++++++
 test/test_checksums.py |  46 +++++++++
 6 files changed, 356 insertions(+), 1 deletion(-)
 create mode 100644 source/xxhash.c

diff --git a/awscrt/checksums.py b/awscrt/checksums.py
index abade6e61..54f8b0b84 100644
--- a/awscrt/checksums.py
+++ b/awscrt/checksums.py
@@ -111,3 +111,63 @@ def combine_crc64nvme(crc64nvme_result1: int, crc64nvme_result2: int, data_lengt
         The combined CRC64-NVME checksum as if computed over the concatenated data
     """
     return _awscrt.checksums_crc64nvme_combine(crc64nvme_result1, crc64nvme_result2, data_length2)
+
+class XXHash(NativeResource):
+    def __init__(self, binding):
+        super().__init__()
+        self._binding = binding
+
+    @staticmethod
+    def new_xxhash64(seed: int = 0) -> 'XXHash':
+        """
+        Generates a new instance of XXHash64 hash.
+        """
+        return XXHash(binding=_awscrt.xxhash64_new(seed))
+    
+    @staticmethod
+    def new_xxhash3_64(seed: int = 0) -> 'XXHash':
+        """
+        Generates a new instance of XXHash3_64 hash.
+        """
+        return XXHash(binding=_awscrt.xxhash3_64_new(seed))
+    
+    @staticmethod
+    def new_xxhash3_128(seed: int = 0) -> 'XXHash':
+        """
+        Generates a new instance of XXHash3_128 hash.
+        """
+        return XXHash(binding=_awscrt.xxhash3_128_new(seed))
+    
+    @staticmethod
+    def compute_xxhash64(input: Union[bytes, bytearray, memoryview], seed: int = 0) -> bytes:
+        """
+        One-shot compute of xxhash64
+        """
+        return _awscrt.xxhash64_compute(input, seed)
+    
+    @staticmethod
+    def compute_xxhash3_64(input: Union[bytes, bytearray, memoryview], seed: int = 0) -> bytes:
+        """
+        One-shot compute of xxhash3_64
+        """
+        return _awscrt.xxhash3_64_compute(input, seed)
+    
+    @staticmethod
+    def compute_xxhash3_128(input: Union[bytes, bytearray, memoryview], seed: int = 0) -> bytes:
+        """
+        One-shot compute of xxhash3_128
+        """
+        return _awscrt.xxhash3_128_compute(input, seed)
+    
+    def update(self, input: Union[bytes, bytearray, memoryview]):
+        """
+        Updates hash with the provided input.
+        """
+        _awscrt.xxhash_update(self._binding, input)
+    
+    def finalize(self) -> bytes:
+        """
+        Finalizes hash.
+        """
+        return _awscrt.xxhash_finalize(self._binding, input)
+
diff --git a/crt/aws-checksums b/crt/aws-checksums
index 270b15acc..c412c6360 160000
--- a/crt/aws-checksums
+++ b/crt/aws-checksums
@@ -1 +1 @@
-Subproject commit 270b15acc1b2125340ec1c6dda6cc3c28ef0fa44
+Subproject commit c412c636091501c2cd544d23664c8d14999e9dcc
diff --git a/source/checksums.h b/source/checksums.h
index cb6464f3e..fd207d6c8 100644
--- a/source/checksums.h
+++ b/source/checksums.h
@@ -13,4 +13,13 @@ PyObject *aws_py_checksums_crc32_combine(PyObject *self, PyObject *args);
 PyObject *aws_py_checksums_crc32c_combine(PyObject *self, PyObject *args);
 PyObject *aws_py_checksums_crc64nvme_combine(PyObject *self, PyObject *args);
 
+PyObject *aws_py_xxhash64_new(PyObject *self, PyObject *args);
+PyObject *aws_py_xxhash3_64_new(PyObject *self, PyObject *args);
+PyObject *aws_py_xxhash3_128_new(PyObject *self, PyObject *args);
+PyObject *aws_py_xxhash64_compute(PyObject *self, PyObject *args);
+PyObject *aws_py_xxhash3_64_compute(PyObject *self, PyObject *args);
+PyObject *aws_py_xxhash3_128_compute(PyObject *self, PyObject *args);
+PyObject *aws_py_xxhash_update(PyObject *self, PyObject *args);
+PyObject *aws_py_xxhash3_finalize(PyObject *self, PyObject *args);
+
 #endif /* AWS_CRT_PYTHON_CHECKSUMS_H */
diff --git a/source/module.c b/source/module.c
index dd346747e..0b752e03d 100644
--- a/source/module.c
+++ b/source/module.c
@@ -863,6 +863,16 @@ static PyMethodDef s_module_methods[] = {
     AWS_PY_METHOD_DEF(checksums_crc32c_combine, METH_VARARGS),
     AWS_PY_METHOD_DEF(checksums_crc64nvme_combine, METH_VARARGS),
 
+    /* XXHash Checksum primitives */
+    AWS_PY_METHOD_DEF(xxhash64_new, METH_VARARGS),
+    AWS_PY_METHOD_DEF(xxhash3_64_new, METH_VARARGS),
+    AWS_PY_METHOD_DEF(xxhash3_128_new, METH_VARARGS),
+    AWS_PY_METHOD_DEF(xxhash64_compute, METH_VARARGS),
+    AWS_PY_METHOD_DEF(xxhash3_64_compute, METH_VARARGS),
+    AWS_PY_METHOD_DEF(xxhash3_128_compute, METH_VARARGS),
+    AWS_PY_METHOD_DEF(xxhash_update, METH_VARARGS),
+    AWS_PY_METHOD_DEF(xxhash_finalize, METH_VARARGS),
+
     /* HTTP */
     AWS_PY_METHOD_DEF(http_connection_close, METH_VARARGS),
     AWS_PY_METHOD_DEF(http_connection_is_open, METH_VARARGS),
diff --git a/source/xxhash.c b/source/xxhash.c
new file mode 100644
index 000000000..fd39bb3d6
--- /dev/null
+++ b/source/xxhash.c
@@ -0,0 +1,230 @@
+/**
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0.
+ */
+
+#include "checksums.h"
+
+#include "aws/checksums/xxhash.h"
+
+const char *s_capsule_name_xxhash = "aws_xxhash";
+
+static void s_xxhash_destructor(PyObject *xxhash_capsule) {
+    struct xxhash *hash = PyCapsule_GetPointer(xxhash_capsule, s_capsule_name_xxhash);
+    assert(hash);
+
+    aws_xxhash_destroy(hash);
+}
+
+PyObject *aws_py_xxhash64_new(PyObject *self, PyObject *args) {
+    PyObject *py_seed;
+
+    if (!PyArg_ParseTuple(args, "O", &py_seed)) {
+        return NULL;
+    }
+
+    uint64_t seed = PyLong_AsUnsignedLongLong(py_seed);
+
+    if (seed == (uint64_t)-1 && PyErr_Occurred()) {
+        return NULL;
+    }
+
+    PyObject *capsule = NULL;
+    struct aws_allocator *allocator = aws_py_get_allocator();
+
+    struct xxhash *hash = aws_xxhash3_128_new(allocator, seed);
+
+    if (hash == NULL) {
+        return PyErr_AwsLastError();
+    }
+
+    capsule = PyCapsule_New(hash, s_capsule_name_xxhash, s_xxhash_destructor);
+
+    if (capsule == NULL) {
+        aws_xxhash_destroy(hash);
+    }
+
+    return capsule;
+}
+
+PyObject *aws_py_xxhash3_64_new(PyObject *self, PyObject *args) {
+    PyObject *py_seed;
+
+    if (!PyArg_ParseTuple(args, "O", &py_seed)) {
+        return NULL;
+    }
+
+    uint64_t seed = PyLong_AsUnsignedLongLong(py_seed);
+
+    if (seed == (uint64_t)-1 && PyErr_Occurred()) {
+        return NULL;
+    }
+
+    PyObject *capsule = NULL;
+    struct aws_allocator *allocator = aws_py_get_allocator();
+
+    struct xxhash *hash = aws_xxhash3_128_new(allocator, seed);
+
+    if (hash == NULL) {
+        return PyErr_AwsLastError();
+    }
+
+    capsule = PyCapsule_New(hash, s_capsule_name_xxhash, s_xxhash_destructor);
+
+    if (capsule == NULL) {
+        aws_xxhash_destroy(hash);
+    }
+
+    return capsule;
+}
+
+PyObject *aws_py_xxhash3_128_new(PyObject *self, PyObject *args) {
+    PyObject *py_seed;
+
+    if (!PyArg_ParseTuple(args, "O", &py_seed)) {
+        return NULL;
+    }
+
+    uint64_t seed = PyLong_AsUnsignedLongLong(py_seed);
+
+    if (seed == (uint64_t)-1 && PyErr_Occurred()) {
+        return NULL;
+    }
+
+    PyObject *capsule = NULL;
+    struct aws_allocator *allocator = aws_py_get_allocator();
+
+    struct xxhash *hash = aws_xxhash3_128_new(allocator, seed);
+
+    if (hash == NULL) {
+        return PyErr_AwsLastError();
+    }
+
+    capsule = PyCapsule_New(hash, s_capsule_name_xxhash, s_xxhash_destructor);
+
+    if (capsule == NULL) {
+        aws_xxhash_destroy(hash);
+    }
+
+    return capsule;
+}
+
+PyObject *aws_py_xxhash64_compute(PyObject *self, PyObject *args) {
+    struct aws_byte_cursor input;
+    PyObject *py_seed;
+    if (!PyArg_ParseTuple(args, "y#0", &input.ptr, &input.len, py_seed)) {
+        return NULL;
+    }
+
+    uint64_t seed = PyLong_AsUnsignedLongLong(py_seed);
+
+    if (seed == (uint64_t)-1 && PyErr_Occurred()) {
+        return NULL;
+    }
+
+    struct aws_allocator *allocator = aws_py_get_allocator();
+    struct aws_byte_buf buf;
+    aws_byte_buf_init(&buf, allocator, 8);
+
+    if (aws_xxhash64_compute(seed, input, &buf)) {
+        return PyErr_AwsLastError();
+    }
+
+    PyObject *ret = PyBytes_FromStringAndSize((const char *)buf.buffer, buf.len);
+    aws_byte_buf_clean_up_secure(&buf);
+    return ret;
+}
+
+PyObject *aws_py_xxhash3_64_compute(PyObject *self, PyObject *args) {
+    struct aws_byte_cursor input;
+    PyObject *py_seed;
+    if (!PyArg_ParseTuple(args, "y#0", &input.ptr, &input.len, py_seed)) {
+        return NULL;
+    }
+
+    uint64_t seed = PyLong_AsUnsignedLongLong(py_seed);
+
+    if (seed == (uint64_t)-1 && PyErr_Occurred()) {
+        return NULL;
+    }
+
+    struct aws_allocator *allocator = aws_py_get_allocator();
+    struct aws_byte_buf buf;
+    aws_byte_buf_init(&buf, allocator, 8);
+
+    if (aws_xxhash3_64_compute(seed, input, &buf)) {
+        return PyErr_AwsLastError();
+    }
+
+    PyObject *ret = PyBytes_FromStringAndSize((const char *)buf.buffer, buf.len);
+    aws_byte_buf_clean_up_secure(&buf);
+    return ret;
+}
+
+PyObject *aws_py_xxhash3_128_compute(PyObject *self, PyObject *args) {
+    struct aws_byte_cursor input;
+    PyObject *py_seed;
+    if (!PyArg_ParseTuple(args, "y#0", &input.ptr, &input.len, py_seed)) {
+        return NULL;
+    }
+
+    uint64_t seed = PyLong_AsUnsignedLongLong(py_seed);
+
+    if (seed == (uint64_t)-1 && PyErr_Occurred()) {
+        return NULL;
+    }
+
+    struct aws_allocator *allocator = aws_py_get_allocator();
+    struct aws_byte_buf buf;
+    aws_byte_buf_init(&buf, allocator, 8);
+
+    if (aws_xxhash3_128_compute(seed, input, &buf)) {
+        return PyErr_AwsLastError();
+    }
+
+    PyObject *ret = PyBytes_FromStringAndSize((const char *)buf.buffer, buf.len);
+    aws_byte_buf_clean_up_secure(&buf);
+    return ret;
+}
+
+PyObject *aws_py_xxhash_update(PyObject *self, PyObject *args) {
+    struct aws_byte_cursor input;
+    PyObject *xxhash_capsule = NULL;
+    if (!PyArg_ParseTuple(args, "y#0", &input.ptr, &input.len, xxhash_capsule)) {
+        return NULL;
+    }
+
+    struct aws_xxhash *hash = PyCapsule_GetPointer(xxhash_capsule, s_capsule_name_xxhash);
+    if (hash == NULL) {
+        return NULL;
+    }
+
+    if (aws_xxhash_update(hash, input)) {
+        PyErr_AwsLastError();
+    }
+}
+
+PyObject *aws_py_xxhash3_finalize(PyObject *self, PyObject *args) {
+    PyObject *xxhash_capsule = NULL;
+    if (!PyArg_ParseTuple(args, "0", xxhash_capsule)) {
+        return NULL;
+    }
+
+    struct aws_xxhash *hash = PyCapsule_GetPointer(xxhash_capsule, s_capsule_name_xxhash);
+    if (hash == NULL) {
+        return NULL;
+    }
+
+    struct aws_allocator *allocator = aws_py_get_allocator();
+    struct aws_byte_buf buf;
+    aws_byte_buf_init(&buf, allocator, 16);
+
+    if (aws_xxhash_finalize(hash, &buf)) {
+        aws_byte_buf_clean_up_secure(buf);
+        return PyErr_AwsLastError();
+    }
+
+    PyObject *ret = PyBytes_FromStringAndSize((const char *)buf.buffer, buf.len);
+    aws_byte_buf_clean_up_secure(&buf);
+    return ret;
+}
diff --git a/test/test_checksums.py b/test/test_checksums.py
index 91890ceb4..3a5ceef08 100644
--- a/test/test_checksums.py
+++ b/test/test_checksums.py
@@ -4,6 +4,7 @@
 
 from test import NativeResourceTest
 from awscrt import checksums
+from awscrt.checksums import XXHash
 import unittest
 import sys
 
@@ -218,6 +219,51 @@ def test_combine_invalid_inputs(self):
             # Result should be an integer
             self.assertIsInstance(result, int)
 
+    def test_xxhash64_piping(self):
+        """Test xxhash64 piping from native side"""
+        data = b"Hello world"
+
+        out = XXHash.compute_xxhash64(data)
+
+        expected = bytes([0xc5, 0x00, 0xb0, 0xc9, 0x12, 0xb3, 0x76, 0xd8])
+
+        self.assertEqual(out, expected)
+
+        hash = XXHash.new_xxhash64()
+        hash.update(data)
+        out2 = hash.finalize()
+        self.assertEqual(out2, expected)
+
+    def test_xxhash3_64_piping(self):
+        """Test xxhash3_64 piping from native side"""
+        data = b"Hello world"
+
+        out = XXHash.compute_xxhash3_64(data)
+
+        expected = bytes([0xb6, 0xac, 0xb9, 0xd8, 0x4a, 0x38, 0xff, 0x74])
+
+        self.assertEqual(out, expected)
+
+        hash = XXHash.new_xxhash3_64()
+        hash.update(data)
+        out2 = hash.finalize()
+        self.assertEqual(out2, expected)
+
+    def test_xxhash3_128_piping(self):
+        """Test xxhash3_128 piping from native side"""
+        data = b"Hello world"
+
+        out = XXHash.compute_xxhash3_128(data)
+
+        expected = bytes([0x73, 0x51, 0xf8, 0x98, 0x12, 0xf9, 0x73, 0x82, 
+            0xb9, 0x1d, 0x05, 0xb3, 0x1e, 0x04, 0xdd, 0x7f])
+
+        self.assertEqual(out, expected)
+
+        hash = XXHash.new_xxhash3_128()
+        hash.update(data)
+        out2 = hash.finalize()
+        self.assertEqual(out2, expected)
 
 if __name__ == '__main__':
     unittest.main()

From f675378cc93f30e639292f8e1f6024671c4f4db6 Mon Sep 17 00:00:00 2001
From: DmitriyMusatkin <musatkd@amazon.com>
Date: Wed, 11 Feb 2026 01:47:16 -0800
Subject: [PATCH 02/22] fix module

---
 source/xxhash.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/source/xxhash.c b/source/xxhash.c
index fd39bb3d6..21970207f 100644
--- a/source/xxhash.c
+++ b/source/xxhash.c
@@ -204,7 +204,7 @@ PyObject *aws_py_xxhash_update(PyObject *self, PyObject *args) {
     }
 }
 
-PyObject *aws_py_xxhash3_finalize(PyObject *self, PyObject *args) {
+PyObject *aws_py_xxhash_finalize(PyObject *self, PyObject *args) {
     PyObject *xxhash_capsule = NULL;
     if (!PyArg_ParseTuple(args, "0", xxhash_capsule)) {
         return NULL;

From 42b0c22f11a1ad80ebe1ffa53a5785a163a1c529 Mon Sep 17 00:00:00 2001
From: DmitriyMusatkin <musatkd@amazon.com>
Date: Wed, 11 Feb 2026 01:50:56 -0800
Subject: [PATCH 03/22] lint

---
 awscrt/checksums.py    | 16 ++++++++--------
 source/checksums.h     |  2 +-
 test/test_checksums.py |  5 +++--
 3 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/awscrt/checksums.py b/awscrt/checksums.py
index 54f8b0b84..e68cda281 100644
--- a/awscrt/checksums.py
+++ b/awscrt/checksums.py
@@ -112,6 +112,7 @@ def combine_crc64nvme(crc64nvme_result1: int, crc64nvme_result2: int, data_lengt
     """
     return _awscrt.checksums_crc64nvme_combine(crc64nvme_result1, crc64nvme_result2, data_length2)
 
+
 class XXHash(NativeResource):
     def __init__(self, binding):
         super().__init__()
@@ -123,51 +124,50 @@ def new_xxhash64(seed: int = 0) -> 'XXHash':
         Generates a new instance of XXHash64 hash.
         """
         return XXHash(binding=_awscrt.xxhash64_new(seed))
-    
+
     @staticmethod
     def new_xxhash3_64(seed: int = 0) -> 'XXHash':
         """
         Generates a new instance of XXHash3_64 hash.
         """
         return XXHash(binding=_awscrt.xxhash3_64_new(seed))
-    
+
     @staticmethod
     def new_xxhash3_128(seed: int = 0) -> 'XXHash':
         """
         Generates a new instance of XXHash3_128 hash.
         """
         return XXHash(binding=_awscrt.xxhash3_128_new(seed))
-    
+
     @staticmethod
     def compute_xxhash64(input: Union[bytes, bytearray, memoryview], seed: int = 0) -> bytes:
         """
         One-shot compute of xxhash64
         """
         return _awscrt.xxhash64_compute(input, seed)
-    
+
     @staticmethod
     def compute_xxhash3_64(input: Union[bytes, bytearray, memoryview], seed: int = 0) -> bytes:
         """
         One-shot compute of xxhash3_64
         """
         return _awscrt.xxhash3_64_compute(input, seed)
-    
+
     @staticmethod
     def compute_xxhash3_128(input: Union[bytes, bytearray, memoryview], seed: int = 0) -> bytes:
         """
         One-shot compute of xxhash3_128
         """
         return _awscrt.xxhash3_128_compute(input, seed)
-    
+
     def update(self, input: Union[bytes, bytearray, memoryview]):
         """
         Updates hash with the provided input.
         """
         _awscrt.xxhash_update(self._binding, input)
-    
+
     def finalize(self) -> bytes:
         """
         Finalizes hash.
         """
         return _awscrt.xxhash_finalize(self._binding, input)
-
diff --git a/source/checksums.h b/source/checksums.h
index fd207d6c8..7bd5b7441 100644
--- a/source/checksums.h
+++ b/source/checksums.h
@@ -20,6 +20,6 @@ PyObject *aws_py_xxhash64_compute(PyObject *self, PyObject *args);
 PyObject *aws_py_xxhash3_64_compute(PyObject *self, PyObject *args);
 PyObject *aws_py_xxhash3_128_compute(PyObject *self, PyObject *args);
 PyObject *aws_py_xxhash_update(PyObject *self, PyObject *args);
-PyObject *aws_py_xxhash3_finalize(PyObject *self, PyObject *args);
+PyObject *aws_py_xxhash_finalize(PyObject *self, PyObject *args);
 
 #endif /* AWS_CRT_PYTHON_CHECKSUMS_H */
diff --git a/test/test_checksums.py b/test/test_checksums.py
index 3a5ceef08..1e88300e2 100644
--- a/test/test_checksums.py
+++ b/test/test_checksums.py
@@ -255,8 +255,8 @@ def test_xxhash3_128_piping(self):
 
         out = XXHash.compute_xxhash3_128(data)
 
-        expected = bytes([0x73, 0x51, 0xf8, 0x98, 0x12, 0xf9, 0x73, 0x82, 
-            0xb9, 0x1d, 0x05, 0xb3, 0x1e, 0x04, 0xdd, 0x7f])
+        expected = bytes([0x73, 0x51, 0xf8, 0x98, 0x12, 0xf9, 0x73, 0x82,
+                          0xb9, 0x1d, 0x05, 0xb3, 0x1e, 0x04, 0xdd, 0x7f])
 
         self.assertEqual(out, expected)
 
@@ -265,5 +265,6 @@ def test_xxhash3_128_piping(self):
         out2 = hash.finalize()
         self.assertEqual(out2, expected)
 
+
 if __name__ == '__main__':
     unittest.main()

From 4a62f1be7b106acf7027ea4a04c4ef70a1d67754 Mon Sep 17 00:00:00 2001
From: DmitriyMusatkin <musatkd@amazon.com>
Date: Wed, 11 Feb 2026 01:54:38 -0800
Subject: [PATCH 04/22] cast

---
 source/xxhash.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/source/xxhash.c b/source/xxhash.c
index 21970207f..66af80753 100644
--- a/source/xxhash.c
+++ b/source/xxhash.c
@@ -10,7 +10,7 @@
 const char *s_capsule_name_xxhash = "aws_xxhash";
 
 static void s_xxhash_destructor(PyObject *xxhash_capsule) {
-    struct xxhash *hash = PyCapsule_GetPointer(xxhash_capsule, s_capsule_name_xxhash);
+    struct aws_xxhash *hash = PyCapsule_GetPointer(xxhash_capsule, s_capsule_name_xxhash);
     assert(hash);
 
     aws_xxhash_destroy(hash);
@@ -32,7 +32,7 @@ PyObject *aws_py_xxhash64_new(PyObject *self, PyObject *args) {
     PyObject *capsule = NULL;
     struct aws_allocator *allocator = aws_py_get_allocator();
 
-    struct xxhash *hash = aws_xxhash3_128_new(allocator, seed);
+    struct aws_xxhash *hash = aws_xxhash3_128_new(allocator, seed);
 
     if (hash == NULL) {
         return PyErr_AwsLastError();
@@ -63,7 +63,7 @@ PyObject *aws_py_xxhash3_64_new(PyObject *self, PyObject *args) {
     PyObject *capsule = NULL;
     struct aws_allocator *allocator = aws_py_get_allocator();
 
-    struct xxhash *hash = aws_xxhash3_128_new(allocator, seed);
+    struct aws_xxhash *hash = aws_xxhash3_128_new(allocator, seed);
 
     if (hash == NULL) {
         return PyErr_AwsLastError();
@@ -94,7 +94,7 @@ PyObject *aws_py_xxhash3_128_new(PyObject *self, PyObject *args) {
     PyObject *capsule = NULL;
     struct aws_allocator *allocator = aws_py_get_allocator();
 
-    struct xxhash *hash = aws_xxhash3_128_new(allocator, seed);
+    struct aws_xxhash *hash = aws_xxhash3_128_new(allocator, seed);
 
     if (hash == NULL) {
         return PyErr_AwsLastError();

From b628f1c8fd49255a165e528dc17cd64b1de60f55 Mon Sep 17 00:00:00 2001
From: DmitriyMusatkin <musatkd@amazon.com>
Date: Wed, 11 Feb 2026 01:56:57 -0800
Subject: [PATCH 05/22] build

---
 source/xxhash.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/source/xxhash.c b/source/xxhash.c
index 66af80753..bda015bc2 100644
--- a/source/xxhash.c
+++ b/source/xxhash.c
@@ -220,7 +220,7 @@ PyObject *aws_py_xxhash_finalize(PyObject *self, PyObject *args) {
     aws_byte_buf_init(&buf, allocator, 16);
 
     if (aws_xxhash_finalize(hash, &buf)) {
-        aws_byte_buf_clean_up_secure(buf);
+        aws_byte_buf_clean_up_secure(&buf);
         return PyErr_AwsLastError();
     }
 

From 40efdd8e89a67e4b4b674603ae5199a4ba12c834 Mon Sep 17 00:00:00 2001
From: DmitriyMusatkin <musatkd@amazon.com>
Date: Wed, 11 Feb 2026 02:01:22 -0800
Subject: [PATCH 06/22] test fix

---
 test/test_checksums.py | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/test/test_checksums.py b/test/test_checksums.py
index 1e88300e2..51f4b3743 100644
--- a/test/test_checksums.py
+++ b/test/test_checksums.py
@@ -4,11 +4,9 @@
 
 from test import NativeResourceTest
 from awscrt import checksums
-from awscrt.checksums import XXHash
 import unittest
 import sys
 
-
 class TestChecksums(NativeResourceTest):
 
     def test_crc32_zeros_one_shot(self):
@@ -223,13 +221,13 @@ def test_xxhash64_piping(self):
         """Test xxhash64 piping from native side"""
         data = b"Hello world"
 
-        out = XXHash.compute_xxhash64(data)
+        out = checksums.XXHash.compute_xxhash64(data)
 
         expected = bytes([0xc5, 0x00, 0xb0, 0xc9, 0x12, 0xb3, 0x76, 0xd8])
 
         self.assertEqual(out, expected)
 
-        hash = XXHash.new_xxhash64()
+        hash = checksums.XXHash.new_xxhash64()
         hash.update(data)
         out2 = hash.finalize()
         self.assertEqual(out2, expected)
@@ -238,13 +236,13 @@ def test_xxhash3_64_piping(self):
         """Test xxhash3_64 piping from native side"""
         data = b"Hello world"
 
-        out = XXHash.compute_xxhash3_64(data)
+        out = checksums.XXHash.compute_xxhash3_64(data)
 
         expected = bytes([0xb6, 0xac, 0xb9, 0xd8, 0x4a, 0x38, 0xff, 0x74])
 
         self.assertEqual(out, expected)
 
-        hash = XXHash.new_xxhash3_64()
+        hash = checksums.XXHash.new_xxhash3_64()
         hash.update(data)
         out2 = hash.finalize()
         self.assertEqual(out2, expected)
@@ -253,14 +251,14 @@ def test_xxhash3_128_piping(self):
         """Test xxhash3_128 piping from native side"""
         data = b"Hello world"
 
-        out = XXHash.compute_xxhash3_128(data)
+        out = checksums.XXHash.compute_xxhash3_128(data)
 
         expected = bytes([0x73, 0x51, 0xf8, 0x98, 0x12, 0xf9, 0x73, 0x82,
                           0xb9, 0x1d, 0x05, 0xb3, 0x1e, 0x04, 0xdd, 0x7f])
 
         self.assertEqual(out, expected)
 
-        hash = XXHash.new_xxhash3_128()
+        hash = checksums.XXHash.new_xxhash3_128()
         hash.update(data)
         out2 = hash.finalize()
         self.assertEqual(out2, expected)

From f059d6f4166c90de5b3da7d896a8ad31b00576da Mon Sep 17 00:00:00 2001
From: DmitriyMusatkin <musatkd@amazon.com>
Date: Wed, 11 Feb 2026 02:02:43 -0800
Subject: [PATCH 07/22] lint

---
 test/test_checksums.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/test/test_checksums.py b/test/test_checksums.py
index 51f4b3743..fbe53c31c 100644
--- a/test/test_checksums.py
+++ b/test/test_checksums.py
@@ -7,6 +7,7 @@
 import unittest
 import sys
 
+
 class TestChecksums(NativeResourceTest):
 
     def test_crc32_zeros_one_shot(self):

From 83c54ca89b038dfcb8c0ae061907fccfd4598905 Mon Sep 17 00:00:00 2001
From: DmitriyMusatkin <musatkd@amazon.com>
Date: Wed, 11 Feb 2026 02:06:29 -0800
Subject: [PATCH 08/22] missing headers

---
 awscrt/checksums.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/awscrt/checksums.py b/awscrt/checksums.py
index e68cda281..82b06f356 100644
--- a/awscrt/checksums.py
+++ b/awscrt/checksums.py
@@ -2,6 +2,8 @@
 # SPDX-License-Identifier: Apache-2.0.
 
 import _awscrt
+from awscrt import NativeResource
+from typing import Union
 
 
 def crc32(input: bytes, previous_crc32: int = 0) -> int:

From 08009f0043a3f2d07a8a98098f15f3fbc55b7ac1 Mon Sep 17 00:00:00 2001
From: DmitriyMusatkin <musatkd@amazon.com>
Date: Wed, 11 Feb 2026 12:02:36 -0800
Subject: [PATCH 09/22] buffer

---
 source/xxhash.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/source/xxhash.c b/source/xxhash.c
index bda015bc2..6bf6aa733 100644
--- a/source/xxhash.c
+++ b/source/xxhash.c
@@ -176,7 +176,7 @@ PyObject *aws_py_xxhash3_128_compute(PyObject *self, PyObject *args) {
 
     struct aws_allocator *allocator = aws_py_get_allocator();
     struct aws_byte_buf buf;
-    aws_byte_buf_init(&buf, allocator, 8);
+    aws_byte_buf_init(&buf, allocator, 16);
 
     if (aws_xxhash3_128_compute(seed, input, &buf)) {
         return PyErr_AwsLastError();

From e9d0b739ebf3a1ad542d800fded30c360262d7e3 Mon Sep 17 00:00:00 2001
From: DmitriyMusatkin <musatkd@amazon.com>
Date: Wed, 11 Feb 2026 12:12:08 -0800
Subject: [PATCH 10/22] warnings

---
 source/xxhash.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/source/xxhash.c b/source/xxhash.c
index 6bf6aa733..17975609a 100644
--- a/source/xxhash.c
+++ b/source/xxhash.c
@@ -17,6 +17,7 @@ static void s_xxhash_destructor(PyObject *xxhash_capsule) {
 }
 
 PyObject *aws_py_xxhash64_new(PyObject *self, PyObject *args) {
+    (void)self;
     PyObject *py_seed;
 
     if (!PyArg_ParseTuple(args, "O", &py_seed)) {
@@ -48,6 +49,7 @@ PyObject *aws_py_xxhash64_new(PyObject *self, PyObject *args) {
 }
 
 PyObject *aws_py_xxhash3_64_new(PyObject *self, PyObject *args) {
+    (void)self;
     PyObject *py_seed;
 
     if (!PyArg_ParseTuple(args, "O", &py_seed)) {
@@ -79,6 +81,7 @@ PyObject *aws_py_xxhash3_64_new(PyObject *self, PyObject *args) {
 }
 
 PyObject *aws_py_xxhash3_128_new(PyObject *self, PyObject *args) {
+    (void)self;
     PyObject *py_seed;
 
     if (!PyArg_ParseTuple(args, "O", &py_seed)) {
@@ -110,6 +113,7 @@ PyObject *aws_py_xxhash3_128_new(PyObject *self, PyObject *args) {
 }
 
 PyObject *aws_py_xxhash64_compute(PyObject *self, PyObject *args) {
+    (void)self;
     struct aws_byte_cursor input;
     PyObject *py_seed;
     if (!PyArg_ParseTuple(args, "y#0", &input.ptr, &input.len, py_seed)) {
@@ -136,6 +140,7 @@ PyObject *aws_py_xxhash64_compute(PyObject *self, PyObject *args) {
 }
 
 PyObject *aws_py_xxhash3_64_compute(PyObject *self, PyObject *args) {
+    (void)self;
     struct aws_byte_cursor input;
     PyObject *py_seed;
     if (!PyArg_ParseTuple(args, "y#0", &input.ptr, &input.len, py_seed)) {
@@ -162,6 +167,7 @@ PyObject *aws_py_xxhash3_64_compute(PyObject *self, PyObject *args) {
 }
 
 PyObject *aws_py_xxhash3_128_compute(PyObject *self, PyObject *args) {
+    (void)self;
     struct aws_byte_cursor input;
     PyObject *py_seed;
     if (!PyArg_ParseTuple(args, "y#0", &input.ptr, &input.len, py_seed)) {
@@ -188,6 +194,7 @@ PyObject *aws_py_xxhash3_128_compute(PyObject *self, PyObject *args) {
 }
 
 PyObject *aws_py_xxhash_update(PyObject *self, PyObject *args) {
+    (void)self;
     struct aws_byte_cursor input;
     PyObject *xxhash_capsule = NULL;
     if (!PyArg_ParseTuple(args, "y#0", &input.ptr, &input.len, xxhash_capsule)) {
@@ -205,6 +212,7 @@ PyObject *aws_py_xxhash_update(PyObject *self, PyObject *args) {
 }
 
 PyObject *aws_py_xxhash_finalize(PyObject *self, PyObject *args) {
+    (void)self;
     PyObject *xxhash_capsule = NULL;
     if (!PyArg_ParseTuple(args, "0", xxhash_capsule)) {
         return NULL;

From fd1dd2152e2d6232611908bdcc10edd0ec8e4b4d Mon Sep 17 00:00:00 2001
From: DmitriyMusatkin <musatkd@amazon.com>
Date: Wed, 11 Feb 2026 12:18:14 -0800
Subject: [PATCH 11/22] fix

---
 source/xxhash.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/source/xxhash.c b/source/xxhash.c
index 17975609a..768b8671a 100644
--- a/source/xxhash.c
+++ b/source/xxhash.c
@@ -116,7 +116,7 @@ PyObject *aws_py_xxhash64_compute(PyObject *self, PyObject *args) {
     (void)self;
     struct aws_byte_cursor input;
     PyObject *py_seed;
-    if (!PyArg_ParseTuple(args, "y#0", &input.ptr, &input.len, py_seed)) {
+    if (!PyArg_ParseTuple(args, "y#0", &input.ptr, &input.len, &py_seed)) {
         return NULL;
     }
 
@@ -143,7 +143,7 @@ PyObject *aws_py_xxhash3_64_compute(PyObject *self, PyObject *args) {
     (void)self;
     struct aws_byte_cursor input;
     PyObject *py_seed;
-    if (!PyArg_ParseTuple(args, "y#0", &input.ptr, &input.len, py_seed)) {
+    if (!PyArg_ParseTuple(args, "y#0", &input.ptr, &input.len, &py_seed)) {
         return NULL;
     }
 
@@ -170,7 +170,7 @@ PyObject *aws_py_xxhash3_128_compute(PyObject *self, PyObject *args) {
     (void)self;
     struct aws_byte_cursor input;
     PyObject *py_seed;
-    if (!PyArg_ParseTuple(args, "y#0", &input.ptr, &input.len, py_seed)) {
+    if (!PyArg_ParseTuple(args, "y#0", &input.ptr, &input.len, &py_seed)) {
         return NULL;
     }
 
@@ -197,7 +197,7 @@ PyObject *aws_py_xxhash_update(PyObject *self, PyObject *args) {
     (void)self;
     struct aws_byte_cursor input;
     PyObject *xxhash_capsule = NULL;
-    if (!PyArg_ParseTuple(args, "y#0", &input.ptr, &input.len, xxhash_capsule)) {
+    if (!PyArg_ParseTuple(args, "y#0", &input.ptr, &input.len, &xxhash_capsule)) {
         return NULL;
     }
 
@@ -214,7 +214,7 @@ PyObject *aws_py_xxhash_update(PyObject *self, PyObject *args) {
 PyObject *aws_py_xxhash_finalize(PyObject *self, PyObject *args) {
     (void)self;
     PyObject *xxhash_capsule = NULL;
-    if (!PyArg_ParseTuple(args, "0", xxhash_capsule)) {
+    if (!PyArg_ParseTuple(args, "0", &xxhash_capsule)) {
         return NULL;
     }
 

From 91b52708c179b2369bb52025e146ce8dba1472f6 Mon Sep 17 00:00:00 2001
From: DmitriyMusatkin <musatkd@amazon.com>
Date: Wed, 11 Feb 2026 12:25:47 -0800
Subject: [PATCH 12/22] another warning

---
 source/xxhash.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/source/xxhash.c b/source/xxhash.c
index 768b8671a..b32d0556c 100644
--- a/source/xxhash.c
+++ b/source/xxhash.c
@@ -193,7 +193,7 @@ PyObject *aws_py_xxhash3_128_compute(PyObject *self, PyObject *args) {
     return ret;
 }
 
-PyObject *aws_py_xxhash_update(PyObject *self, PyObject *args) {
+PyObject * aws_py_xxhash_update(PyObject *self, PyObject *args) {
     (void)self;
     struct aws_byte_cursor input;
     PyObject *xxhash_capsule = NULL;
@@ -209,6 +209,8 @@ PyObject *aws_py_xxhash_update(PyObject *self, PyObject *args) {
     if (aws_xxhash_update(hash, input)) {
         PyErr_AwsLastError();
     }
+
+    return NULL;
 }
 
 PyObject *aws_py_xxhash_finalize(PyObject *self, PyObject *args) {

From 6bda5305e039b5eff220ebad77af512b5b1c3ad3 Mon Sep 17 00:00:00 2001
From: DmitriyMusatkin <musatkd@amazon.com>
Date: Wed, 11 Feb 2026 12:40:41 -0800
Subject: [PATCH 13/22] fix format

---
 source/xxhash.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/source/xxhash.c b/source/xxhash.c
index b32d0556c..5fef9977c 100644
--- a/source/xxhash.c
+++ b/source/xxhash.c
@@ -116,7 +116,7 @@ PyObject *aws_py_xxhash64_compute(PyObject *self, PyObject *args) {
     (void)self;
     struct aws_byte_cursor input;
     PyObject *py_seed;
-    if (!PyArg_ParseTuple(args, "y#0", &input.ptr, &input.len, &py_seed)) {
+    if (!PyArg_ParseTuple(args, "y#O", &input.ptr, &input.len, &py_seed)) {
         return NULL;
     }
 
@@ -143,7 +143,7 @@ PyObject *aws_py_xxhash3_64_compute(PyObject *self, PyObject *args) {
     (void)self;
     struct aws_byte_cursor input;
     PyObject *py_seed;
-    if (!PyArg_ParseTuple(args, "y#0", &input.ptr, &input.len, &py_seed)) {
+    if (!PyArg_ParseTuple(args, "y#O", &input.ptr, &input.len, &py_seed)) {
         return NULL;
     }
 
@@ -170,7 +170,7 @@ PyObject *aws_py_xxhash3_128_compute(PyObject *self, PyObject *args) {
     (void)self;
     struct aws_byte_cursor input;
     PyObject *py_seed;
-    if (!PyArg_ParseTuple(args, "y#0", &input.ptr, &input.len, &py_seed)) {
+    if (!PyArg_ParseTuple(args, "y#O", &input.ptr, &input.len, &py_seed)) {
         return NULL;
     }
 
@@ -197,7 +197,7 @@ PyObject * aws_py_xxhash_update(PyObject *self, PyObject *args) {
     (void)self;
     struct aws_byte_cursor input;
     PyObject *xxhash_capsule = NULL;
-    if (!PyArg_ParseTuple(args, "y#0", &input.ptr, &input.len, &xxhash_capsule)) {
+    if (!PyArg_ParseTuple(args, "y#O", &input.ptr, &input.len, &xxhash_capsule)) {
         return NULL;
     }
 
@@ -216,7 +216,7 @@ PyObject * aws_py_xxhash_update(PyObject *self, PyObject *args) {
 PyObject *aws_py_xxhash_finalize(PyObject *self, PyObject *args) {
     (void)self;
     PyObject *xxhash_capsule = NULL;
-    if (!PyArg_ParseTuple(args, "0", &xxhash_capsule)) {
+    if (!PyArg_ParseTuple(args, "O", &xxhash_capsule)) {
         return NULL;
     }
 

From cdd68d2434d8b48549594dfbbbf90ff2f62b8738 Mon Sep 17 00:00:00 2001
From: DmitriyMusatkin <musatkd@amazon.com>
Date: Wed, 11 Feb 2026 12:47:36 -0800
Subject: [PATCH 14/22] order

---
 source/xxhash.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/source/xxhash.c b/source/xxhash.c
index 5fef9977c..118029546 100644
--- a/source/xxhash.c
+++ b/source/xxhash.c
@@ -197,7 +197,7 @@ PyObject * aws_py_xxhash_update(PyObject *self, PyObject *args) {
     (void)self;
     struct aws_byte_cursor input;
     PyObject *xxhash_capsule = NULL;
-    if (!PyArg_ParseTuple(args, "y#O", &input.ptr, &input.len, &xxhash_capsule)) {
+    if (!PyArg_ParseTuple(args, "Oy#", &input.ptr, &input.len, &xxhash_capsule)) {
         return NULL;
     }
 

From e28b0a5e3e2b1c7f41493b3031b281d7b7558306 Mon Sep 17 00:00:00 2001
From: DmitriyMusatkin <musatkd@amazon.com>
Date: Wed, 11 Feb 2026 12:51:44 -0800
Subject: [PATCH 15/22] order

---
 source/xxhash.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/source/xxhash.c b/source/xxhash.c
index 118029546..3ba4d277f 100644
--- a/source/xxhash.c
+++ b/source/xxhash.c
@@ -197,7 +197,7 @@ PyObject * aws_py_xxhash_update(PyObject *self, PyObject *args) {
     (void)self;
     struct aws_byte_cursor input;
     PyObject *xxhash_capsule = NULL;
-    if (!PyArg_ParseTuple(args, "Oy#", &input.ptr, &input.len, &xxhash_capsule)) {
+    if (!PyArg_ParseTuple(args, "Oy#", &xxhash_capsule, &input.ptr, &input.len)) {
         return NULL;
     }
 

From 448029118cb12b48188dc1479133f945ebf44dc8 Mon Sep 17 00:00:00 2001
From: DmitriyMusatkin <musatkd@amazon.com>
Date: Wed, 11 Feb 2026 13:04:54 -0800
Subject: [PATCH 16/22] return none

---
 source/xxhash.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/source/xxhash.c b/source/xxhash.c
index 3ba4d277f..6d1b661b7 100644
--- a/source/xxhash.c
+++ b/source/xxhash.c
@@ -210,7 +210,7 @@ PyObject * aws_py_xxhash_update(PyObject *self, PyObject *args) {
         PyErr_AwsLastError();
     }
 
-    return NULL;
+    return Py_RETURN_NONE;
 }
 
 PyObject *aws_py_xxhash_finalize(PyObject *self, PyObject *args) {

From 9b95d511b703f60c91919380ef4e36c21bc76c19 Mon Sep 17 00:00:00 2001
From: DmitriyMusatkin <musatkd@amazon.com>
Date: Wed, 11 Feb 2026 13:12:02 -0800
Subject: [PATCH 17/22] ugh

---
 source/xxhash.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/source/xxhash.c b/source/xxhash.c
index 6d1b661b7..008c4ea36 100644
--- a/source/xxhash.c
+++ b/source/xxhash.c
@@ -210,7 +210,7 @@ PyObject * aws_py_xxhash_update(PyObject *self, PyObject *args) {
         PyErr_AwsLastError();
     }
 
-    return Py_RETURN_NONE;
+    Py_RETURN_NONE;
 }
 
 PyObject *aws_py_xxhash_finalize(PyObject *self, PyObject *args) {

From d6cd32e2bd5043f82320bef765360a2fa9229021 Mon Sep 17 00:00:00 2001
From: DmitriyMusatkin <musatkd@amazon.com>
Date: Wed, 11 Feb 2026 13:17:02 -0800
Subject: [PATCH 18/22] finalize

---
 awscrt/checksums.py | 2 +-
 source/xxhash.c     | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/awscrt/checksums.py b/awscrt/checksums.py
index 82b06f356..d2145109b 100644
--- a/awscrt/checksums.py
+++ b/awscrt/checksums.py
@@ -172,4 +172,4 @@ def finalize(self) -> bytes:
         """
         Finalizes hash.
         """
-        return _awscrt.xxhash_finalize(self._binding, input)
+        return _awscrt.xxhash_finalize(self._binding)
diff --git a/source/xxhash.c b/source/xxhash.c
index 008c4ea36..b2c2af4e2 100644
--- a/source/xxhash.c
+++ b/source/xxhash.c
@@ -193,7 +193,7 @@ PyObject *aws_py_xxhash3_128_compute(PyObject *self, PyObject *args) {
     return ret;
 }
 
-PyObject * aws_py_xxhash_update(PyObject *self, PyObject *args) {
+PyObject *aws_py_xxhash_update(PyObject *self, PyObject *args) {
     (void)self;
     struct aws_byte_cursor input;
     PyObject *xxhash_capsule = NULL;

From 5642cef04c5ef3e07454afce64bd1246f02b49cf Mon Sep 17 00:00:00 2001
From: DmitriyMusatkin <musatkd@amazon.com>
Date: Wed, 11 Feb 2026 13:32:09 -0800
Subject: [PATCH 19/22] typo

---
 source/xxhash.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/source/xxhash.c b/source/xxhash.c
index b2c2af4e2..1700f1a78 100644
--- a/source/xxhash.c
+++ b/source/xxhash.c
@@ -33,7 +33,7 @@ PyObject *aws_py_xxhash64_new(PyObject *self, PyObject *args) {
     PyObject *capsule = NULL;
     struct aws_allocator *allocator = aws_py_get_allocator();
 
-    struct aws_xxhash *hash = aws_xxhash3_128_new(allocator, seed);
+    struct aws_xxhash *hash = aws_xxhash64_new(allocator, seed);
 
     if (hash == NULL) {
         return PyErr_AwsLastError();
@@ -65,7 +65,7 @@ PyObject *aws_py_xxhash3_64_new(PyObject *self, PyObject *args) {
     PyObject *capsule = NULL;
     struct aws_allocator *allocator = aws_py_get_allocator();
 
-    struct aws_xxhash *hash = aws_xxhash3_128_new(allocator, seed);
+    struct aws_xxhash *hash = aws_xxhash3_64_new(allocator, seed);
 
     if (hash == NULL) {
         return PyErr_AwsLastError();

From e2ca23e32192031e75cdd4a636df934814f4eacd Mon Sep 17 00:00:00 2001
From: DmitriyMusatkin <musatkd@amazon.com>
Date: Wed, 11 Feb 2026 13:49:20 -0800
Subject: [PATCH 20/22] Add attribution note

---
 NOTICE    | 27 +++++++++++++++++++++++++++
 README.md |  3 +++
 2 files changed, 30 insertions(+)

diff --git a/NOTICE b/NOTICE
index 64177a4eb..3e1163c07 100644
--- a/NOTICE
+++ b/NOTICE
@@ -1,3 +1,30 @@
 AWS Crt Python
 Copyright 2018 Amazon.com, Inc. or its affiliates. All Rights Reserved. 
 SPDX-License-Identifier: Apache-2.0.
+
+** XXHash - https://xxhash.com/
+Copyright (c) 2012-2021 Yann Collet
+All rights reserved.
+
+BSD 2-Clause License (https://www.opensource.org/licenses/bsd-license.php)
+
+Redistribution and use in source and binary forms, with or without modification,
+are permitted provided that the following conditions are met:
+
+* Redistributions of source code must retain the above copyright notice, this
+  list of conditions and the following disclaimer.
+
+* Redistributions in binary form must reproduce the above copyright notice, this
+  list of conditions and the following disclaimer in the documentation and/or
+  other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/README.md b/README.md
index 43d019a9e..63082cb08 100644
--- a/README.md
+++ b/README.md
@@ -147,3 +147,6 @@ AWS_EXTRA_LIB_DIR=C:\path\to\libs;D:\another\path python3 -m pip install .
 ### Windows SDK Version
 
 aws-crt-python builds against windows sdk version `10.0.17763.0` . This is the minimal version required for TLS  1.3 support on Windows. If you need a different Windows SDK version, you can set environment variable `AWS_CRT_WINDOWS_SDK_VERSION=<version>` while building from source:
+
+### Attribution
+This library exposes native XXHash implementation (https://github.com/Cyan4973/xxHash).

From 2854b73432a686d6970cded45c261a2c965cecf8 Mon Sep 17 00:00:00 2001
From: DmitriyMusatkin <musatkd@amazon.com>
Date: Wed, 11 Feb 2026 15:06:59 -0800
Subject: [PATCH 21/22] error hadnling

---
 source/xxhash.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/source/xxhash.c b/source/xxhash.c
index 1700f1a78..95d8a93a1 100644
--- a/source/xxhash.c
+++ b/source/xxhash.c
@@ -131,6 +131,7 @@ PyObject *aws_py_xxhash64_compute(PyObject *self, PyObject *args) {
     aws_byte_buf_init(&buf, allocator, 8);
 
     if (aws_xxhash64_compute(seed, input, &buf)) {
+        aws_byte_buf_clean_up_secure(&buf);
         return PyErr_AwsLastError();
     }
 
@@ -158,6 +159,7 @@ PyObject *aws_py_xxhash3_64_compute(PyObject *self, PyObject *args) {
     aws_byte_buf_init(&buf, allocator, 8);
 
     if (aws_xxhash3_64_compute(seed, input, &buf)) {
+        aws_byte_buf_clean_up_secure(&buf);
         return PyErr_AwsLastError();
     }
 
@@ -185,6 +187,7 @@ PyObject *aws_py_xxhash3_128_compute(PyObject *self, PyObject *args) {
     aws_byte_buf_init(&buf, allocator, 16);
 
     if (aws_xxhash3_128_compute(seed, input, &buf)) {
+        aws_byte_buf_clean_up_secure(&buf);
         return PyErr_AwsLastError();
     }
 

From 57067b260d30c24ed5ac578fd3a11de6e0d3b799 Mon Sep 17 00:00:00 2001
From: DmitriyMusatkin <musatkd@amazon.com>
Date: Wed, 11 Feb 2026 22:43:14 -0800
Subject: [PATCH 22/22] add return

---
 source/xxhash.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/source/xxhash.c b/source/xxhash.c
index 95d8a93a1..1fd36b22a 100644
--- a/source/xxhash.c
+++ b/source/xxhash.c
@@ -210,7 +210,7 @@ PyObject *aws_py_xxhash_update(PyObject *self, PyObject *args) {
     }
 
     if (aws_xxhash_update(hash, input)) {
-        PyErr_AwsLastError();
+        return PyErr_AwsLastError();
     }
 
     Py_RETURN_NONE;