From 5a149640c021015b609f73aa8d12c1bcc2eec02a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ra=C3=BAl=20Cumplido?= <raulcumplido@gmail.com>
Date: Thu, 23 Apr 2026 13:19:17 +0200
Subject: [PATCH 01/22] GH-49321: [C++][Python] Add pixi build for Arrow and
 PyArrow

---
 ci/docker/pixi-cpp.dockerfile | 39 ++++++++++++++++++++++
 ci/pixi/.gitignore            | 19 +++++++++++
 ci/pixi/pixi.toml             | 62 +++++++++++++++++++++++++++++++++++
 compose.yaml                  | 29 ++++++++++++++++
 dev/tasks/tasks.yml           |  6 ++++
 5 files changed, 155 insertions(+)
 create mode 100644 ci/docker/pixi-cpp.dockerfile
 create mode 100644 ci/pixi/.gitignore
 create mode 100644 ci/pixi/pixi.toml

diff --git a/ci/docker/pixi-cpp.dockerfile b/ci/docker/pixi-cpp.dockerfile
new file mode 100644
index 000000000000..41efd45d10db
--- /dev/null
+++ b/ci/docker/pixi-cpp.dockerfile
@@ -0,0 +1,39 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+ARG arch=amd64
+FROM ${arch}/ubuntu:24.04
+
+# install build essentials
+RUN export DEBIAN_FRONTEND=noninteractive && \
+    apt-get update -y -q && \
+    apt-get install -y -q \
+    curl \
+    gdb \
+    libc6-dbg \
+    tzdata \
+    wget && \
+    apt-get clean && \
+    rm -rf /var/lib/apt/lists/*
+
+# install pixi
+RUN curl -fsSL https://pixi.sh/install.sh -o /tmp/install-pixi.sh
+RUN PIXI_HOME=/opt/pixi PIXI_NO_PATH_UPDATE=1 sh /tmp/install-pixi.sh && rm /tmp/install-pixi.sh
+ENV PATH=/opt/pixi/bin:$PATH
+
+# Verify pixi installation
+RUN pixi --version
\ No newline at end of file
diff --git a/ci/pixi/.gitignore b/ci/pixi/.gitignore
new file mode 100644
index 000000000000..a4ac42feacaa
--- /dev/null
+++ b/ci/pixi/.gitignore
@@ -0,0 +1,19 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+**/.pixi
+**/pixi.lock
\ No newline at end of file
diff --git a/ci/pixi/pixi.toml b/ci/pixi/pixi.toml
new file mode 100644
index 000000000000..cad28b928fbc
--- /dev/null
+++ b/ci/pixi/pixi.toml
@@ -0,0 +1,62 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+[workspace]
+channels = ["https://prefix.dev/conda-forge"]
+platforms = ["linux-64", "linux-aarch64", "osx-arm64"]
+preview = ["pixi-build"]
+
+[environments]
+default = []
+test    = ["test"]
+
+[feature.test.activation.env]                                                                                                                                                                                       
+ARROW_TEST_DATA = "/arrow/testing/data"
+
+[feature.test.dependencies]
+binutils = "*"
+cmake = "*"
+python = "*"
+                                                                                                                                                                                           
+[feature.test.tasks]
+# This path mangling feels extremely finicky. Investigate alternatives to make this more robust.
+test = "cd $(ls -d /arrow/ci/pixi/.pixi/build/work/arrow-cpp-*/work/build | head -n 1) && ctest --output-on-failure"
+                                                                                                                                                                                                                      
+[package]
+name = "arrow-cpp"
+# TODO: Incorporate this to the bump version script and tests
+version = "25.0.0.dev"
+authors = ["Apache Arrow"]
+
+[package.build]
+source.path = "../../cpp"
+
+[package.build.backend]
+name = "pixi-build-cmake"
+version = "*"
+
+[package.build.config]
+extra-args = ["-DCMAKE_BUILD_TYPE=Release",
+              "-DARROW_BUILD_TESTS=ON"]
+
+[package.host-dependencies]
+gflags = "*"
+gmock  = ">=1.10.0"
+gtest  = ">=1.10.0"
+libboost-devel = "*"
+rapidjson = "*"
+xsimd = ">=14.0"
diff --git a/compose.yaml b/compose.yaml
index c13bd831ecff..b298f93a0824 100644
--- a/compose.yaml
+++ b/compose.yaml
@@ -138,6 +138,8 @@ x-hierarchy:
   - fedora-cpp:
     - fedora-python
   - fedora-r-clang
+  - pixi-cpp:
+    - pixi-python
   - python-sdist
   - ubuntu-cpp:
     - ubuntu-cpp-static
@@ -200,6 +202,8 @@ volumes:
     name: python-wheel-manylinux-2-28-ccache
   python-wheel-musllinux-1-2-ccache:
     name: python-wheel-musllinux-1-2-ccache
+  pixi-cpp-build:
+    name: ${ARCH}-pixi-cpp-build
   ubuntu-ccache:
     name: ${ARCH_SHORT}-ubuntu-${UBUNTU}-ccache
 
@@ -1144,6 +1148,31 @@ services:
         /arrow/ci/scripts/cpp_build.sh /arrow /build &&
         /arrow/ci/scripts/python_sdist_test.sh /arrow"
 
+  ############################  Pixi builds  ##################################
+
+  pixi-cpp:
+    # C++ build with pixi
+    #
+    # Usage:
+    #   docker compose build pixi-cpp
+    #   docker compose run --rm pixi-cpp
+    # Parameters:
+    #   ARCH: amd64, arm32v7
+    image: ${REPO}:${ARCH}-pixi
+    build:
+      context: .
+      dockerfile: ci/docker/pixi-cpp.dockerfile
+      cache_from:
+        - ${REPO}:${ARCH}-pixi-cpp
+      args:
+        arch: ${ARCH}
+    volumes:
+      - .:/arrow:delegated
+      - ${DOCKER_VOLUME_PREFIX}pixi-cpp-build:/arrow/ci/pixi/.pixi:delegated
+    command:  >
+      /bin/sh -c "pixi build --path /arrow/ci/pixi &&
+        pixi run --environment test --manifest-path /arrow/ci/pixi test"
+
   ############################ Python wheels ##################################
 
   # See available versions at:
diff --git a/dev/tasks/tasks.yml b/dev/tasks/tasks.yml
index f7cb2b92addd..c5477314025d 100644
--- a/dev/tasks/tasks.yml
+++ b/dev/tasks/tasks.yml
@@ -364,6 +364,12 @@ tasks:
     params:
       image: conda-cpp-valgrind
 
+  test-pixi-cpp:
+    ci: github
+    template: docker-tests/github.linux.yml
+    params:
+      image: pixi-cpp
+
   test-ubuntu-22.04-cpp:
     ci: github
     template: docker-tests/github.linux.yml

From bc67422116544972931a1f8349b90f8b60d4eec9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ra=C3=BAl=20Cumplido?= <raulcumplido@gmail.com>
Date: Thu, 23 Apr 2026 13:21:31 +0200
Subject: [PATCH 02/22] Minor clean-up

---
 ci/docker/pixi-cpp.dockerfile | 2 +-
 ci/pixi/.gitignore            | 2 +-
 compose.yaml                  | 3 +--
 3 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/ci/docker/pixi-cpp.dockerfile b/ci/docker/pixi-cpp.dockerfile
index 41efd45d10db..1976253a9676 100644
--- a/ci/docker/pixi-cpp.dockerfile
+++ b/ci/docker/pixi-cpp.dockerfile
@@ -36,4 +36,4 @@ RUN PIXI_HOME=/opt/pixi PIXI_NO_PATH_UPDATE=1 sh /tmp/install-pixi.sh && rm /tmp
 ENV PATH=/opt/pixi/bin:$PATH
 
 # Verify pixi installation
-RUN pixi --version
\ No newline at end of file
+RUN pixi --version
diff --git a/ci/pixi/.gitignore b/ci/pixi/.gitignore
index a4ac42feacaa..8913651c86dc 100644
--- a/ci/pixi/.gitignore
+++ b/ci/pixi/.gitignore
@@ -16,4 +16,4 @@
 # under the License.
 
 **/.pixi
-**/pixi.lock
\ No newline at end of file
+**/pixi.lock
diff --git a/compose.yaml b/compose.yaml
index b298f93a0824..5415b4453062 100644
--- a/compose.yaml
+++ b/compose.yaml
@@ -138,8 +138,7 @@ x-hierarchy:
   - fedora-cpp:
     - fedora-python
   - fedora-r-clang
-  - pixi-cpp:
-    - pixi-python
+  - pixi-cpp
   - python-sdist
   - ubuntu-cpp:
     - ubuntu-cpp-static

From 5f20e90e1bc387912ab5e3c82f2924ad9ef684dc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ra=C3=BAl=20Cumplido?= <raulcumplido@gmail.com>
Date: Fri, 24 Apr 2026 14:27:49 +0200
Subject: [PATCH 03/22] Add pixi build for Python

---
 .../{pixi-cpp.dockerfile => pixi.dockerfile}  |  0
 ci/pixi/{ => cpp}/pixi.toml                   | 35 +++++++-
 ci/pixi/python/pixi.toml                      | 85 +++++++++++++++++++
 compose.yaml                                  | 37 ++++++--
 dev/tasks/tasks.yml                           |  6 ++
 5 files changed, 151 insertions(+), 12 deletions(-)
 rename ci/docker/{pixi-cpp.dockerfile => pixi.dockerfile} (100%)
 rename ci/pixi/{ => cpp}/pixi.toml (72%)
 create mode 100644 ci/pixi/python/pixi.toml

diff --git a/ci/docker/pixi-cpp.dockerfile b/ci/docker/pixi.dockerfile
similarity index 100%
rename from ci/docker/pixi-cpp.dockerfile
rename to ci/docker/pixi.dockerfile
diff --git a/ci/pixi/pixi.toml b/ci/pixi/cpp/pixi.toml
similarity index 72%
rename from ci/pixi/pixi.toml
rename to ci/pixi/cpp/pixi.toml
index cad28b928fbc..6dc4ef5809fe 100644
--- a/ci/pixi/pixi.toml
+++ b/ci/pixi/cpp/pixi.toml
@@ -34,7 +34,7 @@ python = "*"
                                                                                                                                                                                            
 [feature.test.tasks]
 # This path mangling feels extremely finicky. Investigate alternatives to make this more robust.
-test = "cd $(ls -d /arrow/ci/pixi/.pixi/build/work/arrow-cpp-*/work/build | head -n 1) && ctest --output-on-failure"
+test = "cd $(ls -d /arrow/ci/pixi/cpp/.pixi/build/work/arrow-cpp-*/work/build | head -n 1) && ctest --output-on-failure"
                                                                                                                                                                                                                       
 [package]
 name = "arrow-cpp"
@@ -43,20 +43,47 @@ version = "25.0.0.dev"
 authors = ["Apache Arrow"]
 
 [package.build]
-source.path = "../../cpp"
+source.path = "../../../cpp"
 
 [package.build.backend]
 name = "pixi-build-cmake"
 version = "*"
 
 [package.build.config]
-extra-args = ["-DCMAKE_BUILD_TYPE=Release",
-              "-DARROW_BUILD_TESTS=ON"]
+extra-args = [
+  "-DCMAKE_BUILD_TYPE=Release",
+  "-DARROW_BUILD_TESTS=ON",
+  "-DARROW_COMPUTE=ON",
+  "-DARROW_CSV=ON",
+  "-DARROW_DATASET=ON",
+  "-DARROW_FILESYSTEM=ON",
+  "-DARROW_JSON=ON",
+  "-DARROW_PARQUET=ON",
+  "-DARROW_WITH_BROTLI=ON",
+  "-DARROW_WITH_BZ2=ON",
+  "-DARROW_WITH_LZ4=ON",
+  "-DARROW_WITH_SNAPPY=ON",
+  "-DARROW_WITH_ZLIB=ON",
+  "-DARROW_WITH_ZSTD=ON",
+  # libutf8proc on package-host-dependencies seems to fail.
+  # More investigation needed. In the meantime use bundled.
+  "-Dutf8proc_SOURCE=BUNDLED",
+  "-DOPENSSL_ROOT_DIR=$PREFIX",
+]
 
 [package.host-dependencies]
+brotli = "*"
+bzip2 = "*"
 gflags = "*"
 gmock  = ">=1.10.0"
 gtest  = ">=1.10.0"
 libboost-devel = "*"
+lz4-c = "*"
+openssl = "*"
 rapidjson = "*"
+re2 = "*"
+snappy = "*"
+thrift-cpp = ">=0.11.0"
 xsimd = ">=14.0"
+zlib = "*"
+zstd = "*"
diff --git a/ci/pixi/python/pixi.toml b/ci/pixi/python/pixi.toml
new file mode 100644
index 000000000000..6d096882d255
--- /dev/null
+++ b/ci/pixi/python/pixi.toml
@@ -0,0 +1,85 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+[workspace]
+channels = ["https://prefix.dev/conda-forge"]
+platforms = ["linux-64", "linux-aarch64", "osx-arm64"]
+preview = ["pixi-build"]
+
+[environments]
+default = []
+test    = ["test"]
+
+[feature.test]
+platforms = ["linux-64"]
+
+[feature.test.activation.env]
+ARROW_TEST_DATA = "/arrow/testing/data"
+PARQUET_TEST_DATA = "/arrow/cpp/submodules/parquet-testing/data"
+
+[feature.test.dependencies]
+hypothesis = "*"
+pyarrow = { path = "." }
+pytest = "*"
+pytest-timeout = "*"
+
+[feature.test.tasks]
+test = "pytest -r s --pyargs pyarrow --timeout=60"
+
+[package]
+name = "pyarrow"
+# TODO: Incorporate this to the bump version script and tests
+version = "25.0.0.dev"
+authors = ["Apache Arrow"]
+
+[package.build]
+source.path = "../../../python"
+
+[package.build.backend]
+name = "pixi-build-python"
+version = "*"
+
+[package.build.config]
+noarch = false
+compilers = ["c", "cxx"]
+env = {
+  PYARROW_BUNDLE_ARROW_CPP = "0",
+  CMAKE_GENERATOR = "Ninja",
+  ARROW_HOME = "$PREFIX",
+}
+
+[package.host-dependencies]
+arrow-cpp = { path = "../cpp" }   # source-dep on the arrow-cpp manifest
+cmake = "*"
+cython = ">=3.0"
+gcc_linux-64 = "*"
+git = "*"
+gxx_linux-64 = "*"
+ninja = "*"
+numpy = "*"
+pip = "*"
+pkg-config = "*"
+python = ">=3.10,<3.14"
+scikit-build-core = "*"
+setuptools-scm = "*"
+sysroot_linux-64 = "*"
+zlib = "*"
+
+[package.run-dependencies]
+arrow-cpp = { path = "../cpp" }
+python = ">=3.10,<3.14"
+numpy = "*"
diff --git a/compose.yaml b/compose.yaml
index 5415b4453062..7b76b3c9e217 100644
--- a/compose.yaml
+++ b/compose.yaml
@@ -197,12 +197,14 @@ volumes:
     name: ${ARCH_SHORT}-fedora-${FEDORA}-ccache
   maven-cache:
     name: maven-cache
+  pixi-cpp-build:
+    name: ${ARCH}-pixi-cpp-build
+  pixi-python-build:
+    name: ${ARCH}-pixi-python-build
   python-wheel-manylinux-2-28-ccache:
     name: python-wheel-manylinux-2-28-ccache
   python-wheel-musllinux-1-2-ccache:
     name: python-wheel-musllinux-1-2-ccache
-  pixi-cpp-build:
-    name: ${ARCH}-pixi-cpp-build
   ubuntu-ccache:
     name: ${ARCH_SHORT}-ubuntu-${UBUNTU}-ccache
 
@@ -1160,17 +1162,36 @@ services:
     image: ${REPO}:${ARCH}-pixi
     build:
       context: .
-      dockerfile: ci/docker/pixi-cpp.dockerfile
-      cache_from:
-        - ${REPO}:${ARCH}-pixi-cpp
+      dockerfile: ci/docker/pixi.dockerfile
       args:
         arch: ${ARCH}
     volumes:
       - .:/arrow:delegated
-      - ${DOCKER_VOLUME_PREFIX}pixi-cpp-build:/arrow/ci/pixi/.pixi:delegated
+      - ${DOCKER_VOLUME_PREFIX}pixi-cpp-build:/arrow/ci/pixi/cpp/.pixi:delegated
     command:  >
-      /bin/sh -c "pixi build --path /arrow/ci/pixi &&
-        pixi run --environment test --manifest-path /arrow/ci/pixi test"
+      /bin/sh -c "pixi build --path /arrow/ci/pixi/cpp &&
+        pixi run --environment test --manifest-path /arrow/ci/pixi/cpp test"
+
+  pixi-python:
+    # CPython build with pixi
+    #
+    # Usage:
+    #   docker compose build pixi-python
+    #   docker compose run --rm pixi-python
+    # Parameters:
+    #   ARCH: amd64, arm32v7
+    image: ${REPO}:${ARCH}-pixi
+    build:
+      context: .
+      dockerfile: ci/docker/pixi.dockerfile
+      args:
+        arch: ${ARCH}
+    volumes:
+      - .:/arrow:delegated
+      - ${DOCKER_VOLUME_PREFIX}pixi-python-build:/arrow/ci/pixi/python/.pixi:delegated
+    command: >
+      /bin/sh -c "pixi build --path /arrow/ci/pixi/python &&
+        pixi run --environment test --manifest-path /arrow/ci/pixi/python test"
 
   ############################ Python wheels ##################################
 
diff --git a/dev/tasks/tasks.yml b/dev/tasks/tasks.yml
index c5477314025d..9c541ab39f4a 100644
--- a/dev/tasks/tasks.yml
+++ b/dev/tasks/tasks.yml
@@ -370,6 +370,12 @@ tasks:
     params:
       image: pixi-cpp
 
+  test-pixi-python:
+    ci: github
+    template: docker-tests/github.linux.yml
+    params:
+      image: pixi-python
+
   test-ubuntu-22.04-cpp:
     ci: github
     template: docker-tests/github.linux.yml

From 8fdc50168fbbd9ccbe6a3d692a71a7baef875dd8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ra=C3=BAl=20Cumplido?= <raulcumplido@gmail.com>
Date: Fri, 24 Apr 2026 14:36:49 +0200
Subject: [PATCH 04/22] Minor fix to x-hierarchy on compose.yaml

---
 compose.yaml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/compose.yaml b/compose.yaml
index 7b76b3c9e217..4523bbda9e55 100644
--- a/compose.yaml
+++ b/compose.yaml
@@ -139,6 +139,7 @@ x-hierarchy:
     - fedora-python
   - fedora-r-clang
   - pixi-cpp
+  - pixi-python
   - python-sdist
   - ubuntu-cpp:
     - ubuntu-cpp-static

From 612d71fecfee214a5d00399c1c7c1c0822e319ea Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ra=C3=BAl=20Cumplido?= <raulcumplido@gmail.com>
Date: Fri, 24 Apr 2026 16:18:31 +0200
Subject: [PATCH 05/22] Add missing PARQUET_TEST_DATA for arrow cpp build

---
 ci/pixi/cpp/pixi.toml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/ci/pixi/cpp/pixi.toml b/ci/pixi/cpp/pixi.toml
index 6dc4ef5809fe..6dfe95204279 100644
--- a/ci/pixi/cpp/pixi.toml
+++ b/ci/pixi/cpp/pixi.toml
@@ -26,6 +26,7 @@ test    = ["test"]
 
 [feature.test.activation.env]                                                                                                                                                                                       
 ARROW_TEST_DATA = "/arrow/testing/data"
+PARQUET_TEST_DATA = "/arrow/cpp/submodules/parquet-testing/data"
 
 [feature.test.dependencies]
 binutils = "*"

From 4dc5077792a8aa745907a82f2b33f238c98b3513 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ra=C3=BAl=20Cumplido?= <raulcumplido@gmail.com>
Date: Tue, 28 Apr 2026 11:34:29 +0200
Subject: [PATCH 06/22] Add Pixi Arrow CPP sanitizer build

---
 ci/pixi/asan/cpp/pixi.toml             | 98 ++++++++++++++++++++++++++
 ci/pixi/{ => default}/cpp/pixi.toml    |  4 +-
 ci/pixi/{ => default}/python/pixi.toml |  2 +-
 compose.yaml                           | 41 +++++++++--
 dev/tasks/tasks.yml                    | 14 ++--
 5 files changed, 141 insertions(+), 18 deletions(-)
 create mode 100644 ci/pixi/asan/cpp/pixi.toml
 rename ci/pixi/{ => default}/cpp/pixi.toml (94%)
 rename ci/pixi/{ => default}/python/pixi.toml (98%)

diff --git a/ci/pixi/asan/cpp/pixi.toml b/ci/pixi/asan/cpp/pixi.toml
new file mode 100644
index 000000000000..36dad3e146e0
--- /dev/null
+++ b/ci/pixi/asan/cpp/pixi.toml
@@ -0,0 +1,98 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+[workspace]
+channels = ["https://prefix.dev/conda-forge"]
+platforms = ["linux-64"]
+preview = ["pixi-build"]
+
+[environments]
+default = []
+test    = ["test"]
+
+[feature.test.activation.env]
+ARROW_TEST_DATA = "/arrow/testing/data"
+PARQUET_TEST_DATA = "/arrow/cpp/submodules/parquet-testing/data"
+# GH-39973: debug memory pool conflicts with ASAN
+ARROW_DEBUG_MEMORY_POOL = "none"
+ASAN_OPTIONS = "allocator_may_return_null=1:detect_leaks=0:symbolize=1"
+UBSAN_OPTIONS = "print_stacktrace=1"
+
+[feature.test.dependencies]
+binutils = "*"
+cmake = "*"
+python = "*"
+
+[feature.test.tasks]
+# This path mangling feels extremely finicky. Investigate alternatives to make this more robust.
+test = "cd $(ls -d /arrow/ci/pixi/asan/cpp/.pixi/build/work/arrow-cpp-*/work/build | head -n 1) && ctest --output-on-failure"
+
+[package]
+name = "arrow-cpp"
+# TODO: Incorporate this to the bump version script and tests
+version = "25.0.0.dev"
+authors = ["Apache Arrow"]
+
+[package.build]
+source.path = "../../../../cpp"
+
+[package.build.backend]
+name = "pixi-build-cmake"
+version = "*"
+
+[package.build.config]
+extra-args = [
+  "-DCMAKE_BUILD_TYPE=Debug",
+  "-DARROW_USE_ASAN=ON",
+  "-DARROW_USE_UBSAN=ON",
+  # Avoid creating huge static libraries with sanitizer instrumentation
+  "-DARROW_BUILD_STATIC=OFF",
+  "-DARROW_BUILD_TESTS=ON",
+  "-DARROW_COMPUTE=ON",
+  "-DARROW_CSV=ON",
+  "-DARROW_DATASET=ON",
+  "-DARROW_FILESYSTEM=ON",
+  "-DARROW_JSON=ON",
+  "-DARROW_PARQUET=ON",
+  "-DARROW_WITH_BROTLI=ON",
+  "-DARROW_WITH_BZ2=ON",
+  "-DARROW_WITH_LZ4=ON",
+  "-DARROW_WITH_SNAPPY=ON",
+  "-DARROW_WITH_ZLIB=ON",
+  "-DARROW_WITH_ZSTD=ON",
+  # libutf8proc on package-host-dependencies seems to fail.
+  # More investigation needed. In the meantime use bundled.
+  "-Dutf8proc_SOURCE=BUNDLED",
+  "-DOPENSSL_ROOT_DIR=$PREFIX",
+]
+
+[package.host-dependencies]
+brotli = "*"
+bzip2 = "*"
+gflags = "*"
+gmock  = ">=1.10.0"
+gtest  = ">=1.10.0"
+libboost-devel = "*"
+lz4-c = "*"
+openssl = "*"
+rapidjson = "*"
+re2 = "*"
+snappy = "*"
+thrift-cpp = ">=0.11.0"
+xsimd = ">=14.0"
+zlib = "*"
+zstd = "*"
diff --git a/ci/pixi/cpp/pixi.toml b/ci/pixi/default/cpp/pixi.toml
similarity index 94%
rename from ci/pixi/cpp/pixi.toml
rename to ci/pixi/default/cpp/pixi.toml
index 6dfe95204279..ade4d1568511 100644
--- a/ci/pixi/cpp/pixi.toml
+++ b/ci/pixi/default/cpp/pixi.toml
@@ -35,7 +35,7 @@ python = "*"
                                                                                                                                                                                            
 [feature.test.tasks]
 # This path mangling feels extremely finicky. Investigate alternatives to make this more robust.
-test = "cd $(ls -d /arrow/ci/pixi/cpp/.pixi/build/work/arrow-cpp-*/work/build | head -n 1) && ctest --output-on-failure"
+test = "cd $(ls -d /arrow/ci/pixi/default/cpp/.pixi/build/work/arrow-cpp-*/work/build | head -n 1) && ctest --output-on-failure"
                                                                                                                                                                                                                       
 [package]
 name = "arrow-cpp"
@@ -44,7 +44,7 @@ version = "25.0.0.dev"
 authors = ["Apache Arrow"]
 
 [package.build]
-source.path = "../../../cpp"
+source.path = "../../../../cpp"
 
 [package.build.backend]
 name = "pixi-build-cmake"
diff --git a/ci/pixi/python/pixi.toml b/ci/pixi/default/python/pixi.toml
similarity index 98%
rename from ci/pixi/python/pixi.toml
rename to ci/pixi/default/python/pixi.toml
index 6d096882d255..0e753211fdc2 100644
--- a/ci/pixi/python/pixi.toml
+++ b/ci/pixi/default/python/pixi.toml
@@ -47,7 +47,7 @@ version = "25.0.0.dev"
 authors = ["Apache Arrow"]
 
 [package.build]
-source.path = "../../../python"
+source.path = "../../../../python"
 
 [package.build.backend]
 name = "pixi-build-python"
diff --git a/compose.yaml b/compose.yaml
index 4523bbda9e55..b4958234b2b4 100644
--- a/compose.yaml
+++ b/compose.yaml
@@ -138,7 +138,8 @@ x-hierarchy:
   - fedora-cpp:
     - fedora-python
   - fedora-r-clang
-  - pixi-cpp
+  - pixi-cpp:
+    - pixi-cpp-sanitizer
   - pixi-python
   - python-sdist
   - ubuntu-cpp:
@@ -200,6 +201,8 @@ volumes:
     name: maven-cache
   pixi-cpp-build:
     name: ${ARCH}-pixi-cpp-build
+  pixi-cpp-sanitizer-build:
+    name: ${ARCH}-pixi-cpp-sanitizer-build
   pixi-python-build:
     name: ${ARCH}-pixi-python-build
   python-wheel-manylinux-2-28-ccache:
@@ -1168,10 +1171,34 @@ services:
         arch: ${ARCH}
     volumes:
       - .:/arrow:delegated
-      - ${DOCKER_VOLUME_PREFIX}pixi-cpp-build:/arrow/ci/pixi/cpp/.pixi:delegated
+      - ${DOCKER_VOLUME_PREFIX}pixi-cpp-build:/arrow/ci/pixi/default/cpp/.pixi:delegated
     command:  >
-      /bin/sh -c "pixi build --path /arrow/ci/pixi/cpp &&
-        pixi run --environment test --manifest-path /arrow/ci/pixi/cpp test"
+      /bin/sh -c "pixi build --path /arrow/ci/pixi/default/cpp &&
+        pixi run --environment test --manifest-path /arrow/ci/pixi/default/cpp test"
+
+  pixi-cpp-sanitizer:
+    # C++ build with pixi and Address/Undefined Behavior sanitizers enabled
+    #
+    # Usage:
+    #   docker compose build pixi-cpp-sanitizer
+    #   docker compose run --rm pixi-cpp-sanitizer
+    # Parameters:
+    #   ARCH: amd64, arm32v7
+    image: ${REPO}:${ARCH}-pixi
+    cap_add:
+      # For LeakSanitizer
+      - SYS_PTRACE
+    build:
+      context: .
+      dockerfile: ci/docker/pixi.dockerfile
+      args:
+        arch: ${ARCH}
+    volumes:
+      - .:/arrow:delegated
+      - ${DOCKER_VOLUME_PREFIX}pixi-cpp-sanitizer-build:/arrow/ci/pixi/asan/cpp/.pixi:delegated
+    command:  >
+      /bin/sh -c "pixi build --path /arrow/ci/pixi/asan/cpp &&
+        pixi run --environment test --manifest-path /arrow/ci/pixi/asan/cpp test"
 
   pixi-python:
     # CPython build with pixi
@@ -1189,10 +1216,10 @@ services:
         arch: ${ARCH}
     volumes:
       - .:/arrow:delegated
-      - ${DOCKER_VOLUME_PREFIX}pixi-python-build:/arrow/ci/pixi/python/.pixi:delegated
+      - ${DOCKER_VOLUME_PREFIX}pixi-python-build:/arrow/ci/pixi/default/python/.pixi:delegated
     command: >
-      /bin/sh -c "pixi build --path /arrow/ci/pixi/python &&
-        pixi run --environment test --manifest-path /arrow/ci/pixi/python test"
+      /bin/sh -c "pixi build --path /arrow/ci/pixi/default/python &&
+        pixi run --environment test --manifest-path /arrow/ci/pixi/default/python test"
 
   ############################ Python wheels ##################################
 
diff --git a/dev/tasks/tasks.yml b/dev/tasks/tasks.yml
index 9c541ab39f4a..547d57a27f46 100644
--- a/dev/tasks/tasks.yml
+++ b/dev/tasks/tasks.yml
@@ -364,17 +364,15 @@ tasks:
     params:
       image: conda-cpp-valgrind
 
-  test-pixi-cpp:
-    ci: github
-    template: docker-tests/github.linux.yml
-    params:
-      image: pixi-cpp
-
-  test-pixi-python:
+{% for image in ["pixi-cpp",
+                 "pixi-cpp-sanitizer",
+                 "pixi-python"] %}
+  test-{{ image }}:
     ci: github
     template: docker-tests/github.linux.yml
     params:
-      image: pixi-python
+      image: {{ image }}
+{% endfor %}
 
   test-ubuntu-22.04-cpp:
     ci: github

From efb712b88d90340e73e7dee6c3d0334ca7b3375d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ra=C3=BAl=20Cumplido?= <raulcumplido@gmail.com>
Date: Tue, 28 Apr 2026 14:12:57 +0200
Subject: [PATCH 07/22] Initial PyArrow build against sanitizer-instrumented
 CPython, NumPy and Arrow C++

---
 ci/docker/pixi.dockerfile     |  1 +
 ci/pixi/asan/cpp/pixi.toml    |  1 -
 ci/pixi/asan/python/pixi.toml | 98 +++++++++++++++++++++++++++++++++++
 ci/pixi/default/cpp/pixi.toml |  1 -
 compose.yaml                  | 30 ++++++++++-
 5 files changed, 128 insertions(+), 3 deletions(-)
 create mode 100644 ci/pixi/asan/python/pixi.toml

diff --git a/ci/docker/pixi.dockerfile b/ci/docker/pixi.dockerfile
index 1976253a9676..9e91935b191e 100644
--- a/ci/docker/pixi.dockerfile
+++ b/ci/docker/pixi.dockerfile
@@ -24,6 +24,7 @@ RUN export DEBIAN_FRONTEND=noninteractive && \
     apt-get install -y -q \
     curl \
     gdb \
+    git \
     libc6-dbg \
     tzdata \
     wget && \
diff --git a/ci/pixi/asan/cpp/pixi.toml b/ci/pixi/asan/cpp/pixi.toml
index 36dad3e146e0..68934fb06ce8 100644
--- a/ci/pixi/asan/cpp/pixi.toml
+++ b/ci/pixi/asan/cpp/pixi.toml
@@ -35,7 +35,6 @@ UBSAN_OPTIONS = "print_stacktrace=1"
 [feature.test.dependencies]
 binutils = "*"
 cmake = "*"
-python = "*"
 
 [feature.test.tasks]
 # This path mangling feels extremely finicky. Investigate alternatives to make this more robust.
diff --git a/ci/pixi/asan/python/pixi.toml b/ci/pixi/asan/python/pixi.toml
new file mode 100644
index 000000000000..28c710fd069b
--- /dev/null
+++ b/ci/pixi/asan/python/pixi.toml
@@ -0,0 +1,98 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+[workspace]
+channels = ["https://prefix.dev/conda-forge"]
+platforms = ["linux-64"]
+preview = ["pixi-build"]
+
+[environments]
+default = []
+test    = ["test"]
+
+[feature.test]
+platforms = ["linux-64"]
+
+[feature.test.activation.env]
+ARROW_TEST_DATA = "/arrow/testing/data"
+PARQUET_TEST_DATA = "/arrow/cpp/submodules/parquet-testing/data"
+# GH-39973: debug memory pool conflicts with ASAN
+ARROW_DEBUG_MEMORY_POOL = "none"
+ASAN_OPTIONS = "detect_leaks=0:symbolize=1:strict_init_order=true:allocator_may_return_null=1:use_sigaltstack=0"
+UBSAN_OPTIONS = "print_stacktrace=1"
+
+[feature.test.dependencies]
+hypothesis = "*"
+pyarrow = { path = "." }
+pytest = "*"
+pytest-timeout = "*"
+
+[feature.test.tasks]
+test = "pytest -r s --pyargs pyarrow --timeout=60"
+
+[package]
+name = "pyarrow"
+# TODO: Incorporate this to the bump version script and tests
+version = "25.0.0.dev"
+authors = ["Apache Arrow"]
+
+[package.build]
+source.path = "../../../../python"
+
+[package.build.backend]
+name = "pixi-build-python"
+version = "*"
+
+[package.build.config]
+noarch = false
+compilers = ["c", "cxx"]
+env = {
+    PYARROW_BUNDLE_ARROW_CPP = "0",
+    CMAKE_GENERATOR = "Ninja",
+    ARROW_HOME = "$PREFIX",
+    PYARROW_CMAKE_OPTIONS = "-DARROW_USE_ASAN=ON -DARROW_USE_UBSAN=ON -DCMAKE_BUILD_TYPE=Debug",
+    ASAN_OPTIONS = "detect_leaks=0:symbolize=1:strict_init_order=true:allocator_may_return_null=1:use_sigaltstack=0"
+}
+
+[package.host-dependencies]
+# Sanitizer-instrumented Arrow C++ (sibling pixi package).
+arrow-cpp = { path = "../cpp" }
+cmake = "*"
+cython = ">=3.0"
+gcc_linux-64 = "*"
+git = "*"
+gxx_linux-64 = "*"
+ninja = "*"
+pip = "*"
+pkg-config = "*"
+scikit-build-core = "*"
+setuptools-scm = "*"
+sysroot_linux-64 = "*"
+zlib = "*"
+# Instrumented CPython built from source (v3.15.0a6).
+# commit hash must match numpy's pixi-packages/asan pinned commit,
+# so pixi-build doesn't build cpython twice with different versions.
+python.git = "https://github.com/python/cpython"
+python.subdirectory = "Tools/pixi-packages/asan"
+python.rev = "15b216f30d0445469ec31bc7509fcc55a216ef7c"
+# Instrumented NumPy built from source.
+numpy.git = "https://github.com/numpy/numpy"
+numpy.subdirectory = "pixi-packages/asan"
+numpy.rev = "0419105da9cd0a15a4e02bc22019c2b65272c68a"
+
+[package.run-dependencies]
+arrow-cpp = { path = "../cpp" }
diff --git a/ci/pixi/default/cpp/pixi.toml b/ci/pixi/default/cpp/pixi.toml
index ade4d1568511..4386bf592133 100644
--- a/ci/pixi/default/cpp/pixi.toml
+++ b/ci/pixi/default/cpp/pixi.toml
@@ -31,7 +31,6 @@ PARQUET_TEST_DATA = "/arrow/cpp/submodules/parquet-testing/data"
 [feature.test.dependencies]
 binutils = "*"
 cmake = "*"
-python = "*"
                                                                                                                                                                                            
 [feature.test.tasks]
 # This path mangling feels extremely finicky. Investigate alternatives to make this more robust.
diff --git a/compose.yaml b/compose.yaml
index b4958234b2b4..02d78f75f2a5 100644
--- a/compose.yaml
+++ b/compose.yaml
@@ -140,7 +140,8 @@ x-hierarchy:
   - fedora-r-clang
   - pixi-cpp:
     - pixi-cpp-sanitizer
-  - pixi-python
+  - pixi-python:
+    - pixi-python-sanitizer
   - python-sdist
   - ubuntu-cpp:
     - ubuntu-cpp-static
@@ -205,6 +206,8 @@ volumes:
     name: ${ARCH}-pixi-cpp-sanitizer-build
   pixi-python-build:
     name: ${ARCH}-pixi-python-build
+  pixi-python-sanitizer-build:
+    name: ${ARCH}-pixi-python-sanitizer-build
   python-wheel-manylinux-2-28-ccache:
     name: python-wheel-manylinux-2-28-ccache
   python-wheel-musllinux-1-2-ccache:
@@ -1221,6 +1224,31 @@ services:
       /bin/sh -c "pixi build --path /arrow/ci/pixi/default/python &&
         pixi run --environment test --manifest-path /arrow/ci/pixi/default/python test"
 
+  pixi-python-sanitizer:
+    # PyArrow build with pixi against sanitizer-instrumented CPython, NumPy
+    # and Arrow C++. Builds CPython and NumPy from source via pixi-build.
+    #
+    # Usage:
+    #   docker compose build pixi-python-sanitizer
+    #   docker compose run --rm pixi-python-sanitizer
+    # Parameters:
+    #   ARCH: amd64, arm32v7
+    image: ${REPO}:${ARCH}-pixi
+    cap_add:
+      # For LeakSanitizer
+      - SYS_PTRACE
+    build:
+      context: .
+      dockerfile: ci/docker/pixi.dockerfile
+      args:
+        arch: ${ARCH}
+    volumes:
+      - .:/arrow:delegated
+      - ${DOCKER_VOLUME_PREFIX}pixi-python-sanitizer-build:/arrow/ci/pixi/asan/python/.pixi:delegated
+    command: >
+      /bin/sh -c "pixi build --path /arrow/ci/pixi/asan/python &&
+        pixi run --environment test --manifest-path /arrow/ci/pixi/asan/python test"
+
   ############################ Python wheels ##################################
 
   # See available versions at:

From 31b5ad283d9e0b38c7ae88c1c895900128ed698a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ra=C3=BAl=20Cumplido?= <raulcumplido@gmail.com>
Date: Tue, 28 Apr 2026 14:30:20 +0200
Subject: [PATCH 08/22] Add required instrumented numpy and python to test
 dependencies and add missing task for pixi-python-sanitizer

---
 ci/pixi/asan/python/pixi.toml | 6 ++++++
 dev/tasks/tasks.yml           | 3 ++-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/ci/pixi/asan/python/pixi.toml b/ci/pixi/asan/python/pixi.toml
index 28c710fd069b..f57e9c05fad0 100644
--- a/ci/pixi/asan/python/pixi.toml
+++ b/ci/pixi/asan/python/pixi.toml
@@ -40,6 +40,12 @@ hypothesis = "*"
 pyarrow = { path = "." }
 pytest = "*"
 pytest-timeout = "*"
+python.git = "https://github.com/python/cpython"
+python.subdirectory = "Tools/pixi-packages/asan"
+python.rev = "15b216f30d0445469ec31bc7509fcc55a216ef7c"
+numpy.git = "https://github.com/numpy/numpy"
+numpy.subdirectory = "pixi-packages/asan"
+numpy.rev = "0419105da9cd0a15a4e02bc22019c2b65272c68a"
 
 [feature.test.tasks]
 test = "pytest -r s --pyargs pyarrow --timeout=60"
diff --git a/dev/tasks/tasks.yml b/dev/tasks/tasks.yml
index 547d57a27f46..d982e00cb2e5 100644
--- a/dev/tasks/tasks.yml
+++ b/dev/tasks/tasks.yml
@@ -366,7 +366,8 @@ tasks:
 
 {% for image in ["pixi-cpp",
                  "pixi-cpp-sanitizer",
-                 "pixi-python"] %}
+                 "pixi-python",
+                 "pixi-python-sanitizer"] %}
   test-{{ image }}:
     ci: github
     template: docker-tests/github.linux.yml

From 7595696895f8f812d25ceaaf3d96933de7349395 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ra=C3=BAl=20Cumplido?= <raulcumplido@gmail.com>
Date: Tue, 28 Apr 2026 16:13:35 +0200
Subject: [PATCH 09/22] Increase timeout and add ASAN and UBSAN flags to
 PyArrow

---
 ci/pixi/asan/python/pixi.toml | 6 +++++-
 dev/tasks/tasks.yml           | 3 +++
 python/CMakeLists.txt         | 5 +++++
 3 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/ci/pixi/asan/python/pixi.toml b/ci/pixi/asan/python/pixi.toml
index f57e9c05fad0..05cc53fbaf7c 100644
--- a/ci/pixi/asan/python/pixi.toml
+++ b/ci/pixi/asan/python/pixi.toml
@@ -66,11 +66,15 @@ version = "*"
 [package.build.config]
 noarch = false
 compilers = ["c", "cxx"]
+extra-args = [
+    "-Ccmake.build-type=Debug",
+    "-Ccmake.define.ARROW_USE_ASAN=ON",
+    "-Ccmake.define.ARROW_USE_UBSAN=ON",
+]
 env = {
     PYARROW_BUNDLE_ARROW_CPP = "0",
     CMAKE_GENERATOR = "Ninja",
     ARROW_HOME = "$PREFIX",
-    PYARROW_CMAKE_OPTIONS = "-DARROW_USE_ASAN=ON -DARROW_USE_UBSAN=ON -DCMAKE_BUILD_TYPE=Debug",
     ASAN_OPTIONS = "detect_leaks=0:symbolize=1:strict_init_order=true:allocator_may_return_null=1:use_sigaltstack=0"
 }
 
diff --git a/dev/tasks/tasks.yml b/dev/tasks/tasks.yml
index d982e00cb2e5..cd8690a628b8 100644
--- a/dev/tasks/tasks.yml
+++ b/dev/tasks/tasks.yml
@@ -373,6 +373,9 @@ tasks:
     template: docker-tests/github.linux.yml
     params:
       image: {{ image }}
+    {% if image == "pixi-python-sanitizer" %}
+      timeout: 120
+    {% endif %}
 {% endfor %}
 
   test-ubuntu-22.04-cpp:
diff --git a/python/CMakeLists.txt b/python/CMakeLists.txt
index d0ddb9009f89..8fb9afad196f 100644
--- a/python/CMakeLists.txt
+++ b/python/CMakeLists.txt
@@ -158,7 +158,12 @@ if(NOT DEFINED ARROW_RUNTIME_SIMD_LEVEL)
       "MAX"
       CACHE STRING "Max runtime SIMD optimization level")
 endif()
+
+option(ARROW_USE_ASAN "Enable Address Sanitizer checks" OFF)
+option(ARROW_USE_UBSAN "Enable Undefined Behavior sanitizer checks" OFF)
+
 include(SetupCxxFlags)
+include(san-config)
 
 if($ENV{PYODIDE})
   # These variables are needed for building PyArrow on Emscripten.

From 7290be33caa5490e79fa93e46d24a2848cf3a9d5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ra=C3=BAl=20Cumplido?= <raulcumplido@gmail.com>
Date: Tue, 28 Apr 2026 18:12:34 +0200
Subject: [PATCH 10/22] Generate Cython and libarrow_python ASAN failures to
 validate instrumentation

---
 python/pyarrow/includes/libarrow_python.pxd   |  2 ++
 python/pyarrow/lib.pyx                        | 15 +++++++++
 .../pyarrow/src/arrow/python/numpy_convert.cc |  8 +++++
 .../pyarrow/src/arrow/python/numpy_convert.h  |  4 +++
 python/pyarrow/tests/test_misc.py             | 31 +++++++++++++++++++
 5 files changed, 60 insertions(+)

diff --git a/python/pyarrow/includes/libarrow_python.pxd b/python/pyarrow/includes/libarrow_python.pxd
index 385a2924d1da..77604ddb766e 100644
--- a/python/pyarrow/includes/libarrow_python.pxd
+++ b/python/pyarrow/includes/libarrow_python.pxd
@@ -35,6 +35,8 @@ cdef extern from "arrow/python/api.h" namespace "arrow::py":
     # Requires GIL
     CResult[shared_ptr[CDataType]] InferArrowType(
         object obj, object mask, c_bool pandas_null_sentinels)
+    # TODO: ASAN sanity check; heap-buffer-overflow. Revert before final commit.
+    void AsanSanityOobNumpy()
 
 
 cdef extern from "arrow/python/api.h" namespace "arrow::py::internal":
diff --git a/python/pyarrow/lib.pyx b/python/pyarrow/lib.pyx
index 7e97177a6ec0..2e1d74f4bc86 100644
--- a/python/pyarrow/lib.pyx
+++ b/python/pyarrow/lib.pyx
@@ -29,6 +29,7 @@ import os
 import sys
 
 from cython.operator cimport dereference as deref
+from libc.stdlib cimport malloc, free
 from pyarrow.includes.libarrow cimport *
 from pyarrow.includes.libarrow_python cimport *
 from pyarrow.includes.common cimport PyObject_to_object
@@ -85,6 +86,20 @@ def set_cpu_count(int count):
     check_status(SetCpuThreadPoolCapacity(count))
 
 
+def _asan_sanity_oob():
+    # TODO: ASAN sanity check; heap-buffer-overflow. Revert before final commit.
+    cdef int* a = <int*>malloc(sizeof(int))
+    cdef int v = a[100]
+    free(a)
+    return v
+
+
+def _asan_sanity_oob_numpy():
+    # TODO: ASAN sanity check; calls libarrow_python.so's
+    # AsanSanityOobNumpy(). Revert before final commit.
+    libarrow_python.AsanSanityOobNumpy()
+
+
 def is_opentelemetry_enabled() -> bool:
     """
     Returns True if OpenTelemetry is enabled in libarrow.
diff --git a/python/pyarrow/src/arrow/python/numpy_convert.cc b/python/pyarrow/src/arrow/python/numpy_convert.cc
index 6e59835286d9..0fc2a1ba86b0 100644
--- a/python/pyarrow/src/arrow/python/numpy_convert.cc
+++ b/python/pyarrow/src/arrow/python/numpy_convert.cc
@@ -560,5 +560,13 @@ Status TensorToSparseCSFTensor(const std::shared_ptr<Tensor>& tensor,
   return SparseCSFTensor::Make(*tensor).Value(out);
 }
 
+// TODO: ASAN sanity check; heap-buffer-overflow. Revert before final commit.
+void AsanSanityOobNumpy() {
+  int* a = static_cast<int*>(std::malloc(sizeof(int)));
+  volatile int v = a[100];
+  std::free(a);
+  (void)v;
+}
+
 }  // namespace py
 }  // namespace arrow
diff --git a/python/pyarrow/src/arrow/python/numpy_convert.h b/python/pyarrow/src/arrow/python/numpy_convert.h
index 2d1086e13552..0454281854ff 100644
--- a/python/pyarrow/src/arrow/python/numpy_convert.h
+++ b/python/pyarrow/src/arrow/python/numpy_convert.h
@@ -118,5 +118,9 @@ ARROW_PYTHON_EXPORT Status
 TensorToSparseCSFTensor(const std::shared_ptr<Tensor>& tensor,
                         std::shared_ptr<SparseCSFTensor>* csparse_tensor);
 
+// TODO: ASAN sanity check; heap-buffer-overflow in libarrow_python's
+// numpy conversion module. Revert before final commit.
+ARROW_PYTHON_EXPORT void AsanSanityOobNumpy();
+
 }  // namespace py
 }  // namespace arrow
diff --git a/python/pyarrow/tests/test_misc.py b/python/pyarrow/tests/test_misc.py
index 856873f441b4..71be7640e837 100644
--- a/python/pyarrow/tests/test_misc.py
+++ b/python/pyarrow/tests/test_misc.py
@@ -30,6 +30,37 @@ def test_get_include():
     assert os.path.exists(os.path.join(include_dir, 'arrow', 'api.h'))
 
 
+def test_asan_sanity_oob():
+    # TODO: ASAN sanity check (cython side). ASAN aborts the subprocess on
+    # the heap-buffer-overflow; the test fails with the report visible in the
+    # assertion message. Revert before final commit.
+    res = subprocess.run(
+        [sys.executable, "-c",
+         "import pyarrow.lib; pyarrow.lib._asan_sanity_oob()"],
+        capture_output=True, text=True, timeout=30,
+    )
+    assert res.returncode == 0, (
+        f"ASAN caught cython-emitted heap-buffer-overflow.\n"
+        f"returncode={res.returncode}\n"
+        f"stderr:\n{res.stderr}"
+    )
+
+
+def test_asan_sanity_oob_numpy():
+    # TODO: ASAN sanity check (libarrow_python.so / numpy_convert.cc).
+    # Same pattern as test_asan_sanity_oob. Revert before final commit.
+    res = subprocess.run(
+        [sys.executable, "-c",
+         "import pyarrow.lib; pyarrow.lib._asan_sanity_oob_numpy()"],
+        capture_output=True, text=True, timeout=30,
+    )
+    assert res.returncode == 0, (
+        f"ASAN caught heap-buffer-overflow in libarrow_python.\n"
+        f"returncode={res.returncode}\n"
+        f"stderr:\n{res.stderr}"
+    )
+
+
 @pytest.mark.skipif('sys.platform != "win32"')
 def test_get_library_dirs_win32():
     assert any(os.path.exists(os.path.join(directory, 'arrow.lib'))

From 3d9be28a63f98aefdf9f65088eebd25df120fb9b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ra=C3=BAl=20Cumplido?= <raulcumplido@gmail.com>
Date: Wed, 29 Apr 2026 11:58:11 +0200
Subject: [PATCH 11/22] Some minor cleanups

---
 ci/pixi/asan/cpp/pixi.toml       |  1 -
 ci/pixi/asan/python/pixi.toml    | 18 ++++++++++--------
 ci/pixi/default/cpp/pixi.toml    |  1 -
 ci/pixi/default/python/pixi.toml |  2 --
 4 files changed, 10 insertions(+), 12 deletions(-)

diff --git a/ci/pixi/asan/cpp/pixi.toml b/ci/pixi/asan/cpp/pixi.toml
index 68934fb06ce8..3d2fb73c7d11 100644
--- a/ci/pixi/asan/cpp/pixi.toml
+++ b/ci/pixi/asan/cpp/pixi.toml
@@ -21,7 +21,6 @@ platforms = ["linux-64"]
 preview = ["pixi-build"]
 
 [environments]
-default = []
 test    = ["test"]
 
 [feature.test.activation.env]
diff --git a/ci/pixi/asan/python/pixi.toml b/ci/pixi/asan/python/pixi.toml
index 05cc53fbaf7c..cd7044277586 100644
--- a/ci/pixi/asan/python/pixi.toml
+++ b/ci/pixi/asan/python/pixi.toml
@@ -21,7 +21,6 @@ platforms = ["linux-64"]
 preview = ["pixi-build"]
 
 [environments]
-default = []
 test    = ["test"]
 
 [feature.test]
@@ -40,12 +39,6 @@ hypothesis = "*"
 pyarrow = { path = "." }
 pytest = "*"
 pytest-timeout = "*"
-python.git = "https://github.com/python/cpython"
-python.subdirectory = "Tools/pixi-packages/asan"
-python.rev = "15b216f30d0445469ec31bc7509fcc55a216ef7c"
-numpy.git = "https://github.com/numpy/numpy"
-numpy.subdirectory = "pixi-packages/asan"
-numpy.rev = "0419105da9cd0a15a4e02bc22019c2b65272c68a"
 
 [feature.test.tasks]
 test = "pytest -r s --pyargs pyarrow --timeout=60"
@@ -64,7 +57,6 @@ name = "pixi-build-python"
 version = "*"
 
 [package.build.config]
-noarch = false
 compilers = ["c", "cxx"]
 extra-args = [
     "-Ccmake.build-type=Debug",
@@ -106,3 +98,13 @@ numpy.rev = "0419105da9cd0a15a4e02bc22019c2b65272c68a"
 
 [package.run-dependencies]
 arrow-cpp = { path = "../cpp" }
+# The following are necessary to run the Python test suite,
+# which otherwise won't be run with the instrumented Python and NumPy.
+# Important to use the same revisions as in host-dependencies to avoid
+# mismatches between build and test environments.
+python.git = "https://github.com/python/cpython"
+python.subdirectory = "Tools/pixi-packages/asan"
+python.rev = "15b216f30d0445469ec31bc7509fcc55a216ef7c"
+numpy.git = "https://github.com/numpy/numpy"
+numpy.subdirectory = "pixi-packages/asan"
+numpy.rev = "0419105da9cd0a15a4e02bc22019c2b65272c68a"
diff --git a/ci/pixi/default/cpp/pixi.toml b/ci/pixi/default/cpp/pixi.toml
index 4386bf592133..a4b850034f1a 100644
--- a/ci/pixi/default/cpp/pixi.toml
+++ b/ci/pixi/default/cpp/pixi.toml
@@ -21,7 +21,6 @@ platforms = ["linux-64", "linux-aarch64", "osx-arm64"]
 preview = ["pixi-build"]
 
 [environments]
-default = []
 test    = ["test"]
 
 [feature.test.activation.env]                                                                                                                                                                                       
diff --git a/ci/pixi/default/python/pixi.toml b/ci/pixi/default/python/pixi.toml
index 0e753211fdc2..123f3deb4f69 100644
--- a/ci/pixi/default/python/pixi.toml
+++ b/ci/pixi/default/python/pixi.toml
@@ -21,7 +21,6 @@ platforms = ["linux-64", "linux-aarch64", "osx-arm64"]
 preview = ["pixi-build"]
 
 [environments]
-default = []
 test    = ["test"]
 
 [feature.test]
@@ -54,7 +53,6 @@ name = "pixi-build-python"
 version = "*"
 
 [package.build.config]
-noarch = false
 compilers = ["c", "cxx"]
 env = {
   PYARROW_BUNDLE_ARROW_CPP = "0",

From 673edc099b8820e93df6ce0e9068b89c028c4d51 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ra=C3=BAl=20Cumplido?= <raulcumplido@gmail.com>
Date: Wed, 29 Apr 2026 16:22:59 +0200
Subject: [PATCH 12/22] Add expected failures

---
 ci/docker/pixi.dockerfile           | 1 +
 ci/pixi/asan/python/pixi.toml       | 2 +-
 python/pyarrow/tests/test_dlpack.py | 2 ++
 python/pyarrow/tests/test_memory.py | 6 ++++++
 4 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/ci/docker/pixi.dockerfile b/ci/docker/pixi.dockerfile
index 9e91935b191e..f7a810669c31 100644
--- a/ci/docker/pixi.dockerfile
+++ b/ci/docker/pixi.dockerfile
@@ -27,6 +27,7 @@ RUN export DEBIAN_FRONTEND=noninteractive && \
     git \
     libc6-dbg \
     tzdata \
+    tzdata-legacy \
     wget && \
     apt-get clean && \
     rm -rf /var/lib/apt/lists/*
diff --git a/ci/pixi/asan/python/pixi.toml b/ci/pixi/asan/python/pixi.toml
index cd7044277586..01fdc2512576 100644
--- a/ci/pixi/asan/python/pixi.toml
+++ b/ci/pixi/asan/python/pixi.toml
@@ -41,7 +41,7 @@ pytest = "*"
 pytest-timeout = "*"
 
 [feature.test.tasks]
-test = "pytest -r s --pyargs pyarrow --timeout=60"
+test = "pytest -r s --pyargs pyarrow --timeout=180 -m 'not fail_asan'"
 
 [package]
 name = "pyarrow"
diff --git a/python/pyarrow/tests/test_dlpack.py b/python/pyarrow/tests/test_dlpack.py
index 7452c8eb4a13..0f9482fb1b3e 100644
--- a/python/pyarrow/tests/test_dlpack.py
+++ b/python/pyarrow/tests/test_dlpack.py
@@ -55,6 +55,8 @@ def wrapper(*args, **kwargs):
     return wrapper
 
 
+# Asan tests are flacky on check_bytes_allocated assertion.
+@pytest.mark.fail_asan
 @check_bytes_allocated
 @pytest.mark.parametrize(
     ('value_type', 'np_type_str'),
diff --git a/python/pyarrow/tests/test_memory.py b/python/pyarrow/tests/test_memory.py
index 56196bd9c5b3..41df95036068 100644
--- a/python/pyarrow/tests/test_memory.py
+++ b/python/pyarrow/tests/test_memory.py
@@ -257,16 +257,22 @@ def check_debug_memory_pool_disabled(pool_factory, env_value, msg):
         assert msg in res.stderr
 
 
+# Asan test fails as we are doing an out-of-bounds write.
+@pytest.mark.fail_asan
 @pytest.mark.parametrize('pool_factory', supported_factories())
 def test_debug_memory_pool_none(pool_factory):
     check_debug_memory_pool_disabled(pool_factory, "none", "")
 
 
+# Asan test fails as we are doing an out-of-bounds write.
+@pytest.mark.fail_asan
 @pytest.mark.parametrize('pool_factory', supported_factories())
 def test_debug_memory_pool_empty(pool_factory):
     check_debug_memory_pool_disabled(pool_factory, "", "")
 
 
+# Asan test fails as we are doing an out-of-bounds write.
+@pytest.mark.fail_asan
 @pytest.mark.parametrize('pool_factory', supported_factories())
 def test_debug_memory_pool_unknown(pool_factory):
     env_value = "some_arbitrary_value"

From 634bb97ae826b7ba83279efb5a8bafba2b5f5297 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ra=C3=BAl=20Cumplido?= <raulcumplido@gmail.com>
Date: Thu, 30 Apr 2026 16:40:24 +0200
Subject: [PATCH 13/22] Improve ASAN detection and pytest markers

---
 ci/pixi/asan/python/pixi.toml       |  2 +-
 python/pyarrow/conftest.py          | 11 +++++++++++
 python/pyarrow/tests/test_dlpack.py |  2 +-
 python/pyarrow/tests/test_memory.py |  6 +++---
 4 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/ci/pixi/asan/python/pixi.toml b/ci/pixi/asan/python/pixi.toml
index 01fdc2512576..d7fa56349252 100644
--- a/ci/pixi/asan/python/pixi.toml
+++ b/ci/pixi/asan/python/pixi.toml
@@ -41,7 +41,7 @@ pytest = "*"
 pytest-timeout = "*"
 
 [feature.test.tasks]
-test = "pytest -r s --pyargs pyarrow --timeout=180 -m 'not fail_asan'"
+test = "pytest -r s --pyargs pyarrow --timeout=180"
 
 [package]
 name = "pyarrow"
diff --git a/python/pyarrow/conftest.py b/python/pyarrow/conftest.py
index 9fed75dac3ee..004aab236e69 100644
--- a/python/pyarrow/conftest.py
+++ b/python/pyarrow/conftest.py
@@ -17,6 +17,7 @@
 
 import pytest
 
+import ctypes
 import os
 import pyarrow as pa
 from pyarrow import Codec
@@ -25,6 +26,14 @@
 import sys
 
 
+def _is_asan_build():
+    try:
+        ctypes.CDLL(None).__asan_init
+        return True
+    except (OSError, AttributeError):
+        return False
+
+
 groups = [
     'acero',
     'azure',
@@ -43,6 +52,7 @@
     'large_memory',
     'lz4',
     'memory_leak',
+    'noasan',
     'nopandas',
     'nonumpy',
     'numpy',
@@ -80,6 +90,7 @@
     'large_memory': False,
     'lz4': Codec.is_available('lz4'),
     'memory_leak': False,
+    'noasan': not _is_asan_build(),
     'nopandas': False,
     'nonumpy': False,
     'numpy': False,
diff --git a/python/pyarrow/tests/test_dlpack.py b/python/pyarrow/tests/test_dlpack.py
index 0f9482fb1b3e..f9aca70582fa 100644
--- a/python/pyarrow/tests/test_dlpack.py
+++ b/python/pyarrow/tests/test_dlpack.py
@@ -56,7 +56,7 @@ def wrapper(*args, **kwargs):
 
 
 # Asan tests are flacky on check_bytes_allocated assertion.
-@pytest.mark.fail_asan
+@pytest.mark.noasan
 @check_bytes_allocated
 @pytest.mark.parametrize(
     ('value_type', 'np_type_str'),
diff --git a/python/pyarrow/tests/test_memory.py b/python/pyarrow/tests/test_memory.py
index 41df95036068..dc1d185b838e 100644
--- a/python/pyarrow/tests/test_memory.py
+++ b/python/pyarrow/tests/test_memory.py
@@ -258,21 +258,21 @@ def check_debug_memory_pool_disabled(pool_factory, env_value, msg):
 
 
 # Asan test fails as we are doing an out-of-bounds write.
-@pytest.mark.fail_asan
+@pytest.mark.noasan
 @pytest.mark.parametrize('pool_factory', supported_factories())
 def test_debug_memory_pool_none(pool_factory):
     check_debug_memory_pool_disabled(pool_factory, "none", "")
 
 
 # Asan test fails as we are doing an out-of-bounds write.
-@pytest.mark.fail_asan
+@pytest.mark.noasan
 @pytest.mark.parametrize('pool_factory', supported_factories())
 def test_debug_memory_pool_empty(pool_factory):
     check_debug_memory_pool_disabled(pool_factory, "", "")
 
 
 # Asan test fails as we are doing an out-of-bounds write.
-@pytest.mark.fail_asan
+@pytest.mark.noasan
 @pytest.mark.parametrize('pool_factory', supported_factories())
 def test_debug_memory_pool_unknown(pool_factory):
     env_value = "some_arbitrary_value"

From cbaeea272a6c987392eaad74e0d192ed402fbd55 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ra=C3=BAl=20Cumplido?= <raulcumplido@gmail.com>
Date: Thu, 30 Apr 2026 17:46:11 +0200
Subject: [PATCH 14/22] Fix for Windows

---
 python/pyarrow/conftest.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/python/pyarrow/conftest.py b/python/pyarrow/conftest.py
index 004aab236e69..480bf9af4fe7 100644
--- a/python/pyarrow/conftest.py
+++ b/python/pyarrow/conftest.py
@@ -27,6 +27,8 @@
 
 
 def _is_asan_build():
+    if sys.platform == "win32":
+        return False
     try:
         ctypes.CDLL(None).__asan_init
         return True

From be1ed5e2fad7ae040bba2cc459f4619f21ff9d3c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ra=C3=BAl=20Cumplido?= <raulcumplido@gmail.com>
Date: Mon, 4 May 2026 11:36:10 +0200
Subject: [PATCH 15/22] Remove failing tests with OOB

---
 python/pyarrow/includes/libarrow_python.pxd   |  2 --
 python/pyarrow/lib.pyx                        | 14 ---------
 .../pyarrow/src/arrow/python/numpy_convert.cc |  8 -----
 .../pyarrow/src/arrow/python/numpy_convert.h  |  4 ---
 python/pyarrow/tests/test_misc.py             | 31 -------------------
 5 files changed, 59 deletions(-)

diff --git a/python/pyarrow/includes/libarrow_python.pxd b/python/pyarrow/includes/libarrow_python.pxd
index 77604ddb766e..385a2924d1da 100644
--- a/python/pyarrow/includes/libarrow_python.pxd
+++ b/python/pyarrow/includes/libarrow_python.pxd
@@ -35,8 +35,6 @@ cdef extern from "arrow/python/api.h" namespace "arrow::py":
     # Requires GIL
     CResult[shared_ptr[CDataType]] InferArrowType(
         object obj, object mask, c_bool pandas_null_sentinels)
-    # TODO: ASAN sanity check; heap-buffer-overflow. Revert before final commit.
-    void AsanSanityOobNumpy()
 
 
 cdef extern from "arrow/python/api.h" namespace "arrow::py::internal":
diff --git a/python/pyarrow/lib.pyx b/python/pyarrow/lib.pyx
index 2e1d74f4bc86..44183917b66d 100644
--- a/python/pyarrow/lib.pyx
+++ b/python/pyarrow/lib.pyx
@@ -86,20 +86,6 @@ def set_cpu_count(int count):
     check_status(SetCpuThreadPoolCapacity(count))
 
 
-def _asan_sanity_oob():
-    # TODO: ASAN sanity check; heap-buffer-overflow. Revert before final commit.
-    cdef int* a = <int*>malloc(sizeof(int))
-    cdef int v = a[100]
-    free(a)
-    return v
-
-
-def _asan_sanity_oob_numpy():
-    # TODO: ASAN sanity check; calls libarrow_python.so's
-    # AsanSanityOobNumpy(). Revert before final commit.
-    libarrow_python.AsanSanityOobNumpy()
-
-
 def is_opentelemetry_enabled() -> bool:
     """
     Returns True if OpenTelemetry is enabled in libarrow.
diff --git a/python/pyarrow/src/arrow/python/numpy_convert.cc b/python/pyarrow/src/arrow/python/numpy_convert.cc
index 0fc2a1ba86b0..6e59835286d9 100644
--- a/python/pyarrow/src/arrow/python/numpy_convert.cc
+++ b/python/pyarrow/src/arrow/python/numpy_convert.cc
@@ -560,13 +560,5 @@ Status TensorToSparseCSFTensor(const std::shared_ptr<Tensor>& tensor,
   return SparseCSFTensor::Make(*tensor).Value(out);
 }
 
-// TODO: ASAN sanity check; heap-buffer-overflow. Revert before final commit.
-void AsanSanityOobNumpy() {
-  int* a = static_cast<int*>(std::malloc(sizeof(int)));
-  volatile int v = a[100];
-  std::free(a);
-  (void)v;
-}
-
 }  // namespace py
 }  // namespace arrow
diff --git a/python/pyarrow/src/arrow/python/numpy_convert.h b/python/pyarrow/src/arrow/python/numpy_convert.h
index 0454281854ff..2d1086e13552 100644
--- a/python/pyarrow/src/arrow/python/numpy_convert.h
+++ b/python/pyarrow/src/arrow/python/numpy_convert.h
@@ -118,9 +118,5 @@ ARROW_PYTHON_EXPORT Status
 TensorToSparseCSFTensor(const std::shared_ptr<Tensor>& tensor,
                         std::shared_ptr<SparseCSFTensor>* csparse_tensor);
 
-// TODO: ASAN sanity check; heap-buffer-overflow in libarrow_python's
-// numpy conversion module. Revert before final commit.
-ARROW_PYTHON_EXPORT void AsanSanityOobNumpy();
-
 }  // namespace py
 }  // namespace arrow
diff --git a/python/pyarrow/tests/test_misc.py b/python/pyarrow/tests/test_misc.py
index 71be7640e837..856873f441b4 100644
--- a/python/pyarrow/tests/test_misc.py
+++ b/python/pyarrow/tests/test_misc.py
@@ -30,37 +30,6 @@ def test_get_include():
     assert os.path.exists(os.path.join(include_dir, 'arrow', 'api.h'))
 
 
-def test_asan_sanity_oob():
-    # TODO: ASAN sanity check (cython side). ASAN aborts the subprocess on
-    # the heap-buffer-overflow; the test fails with the report visible in the
-    # assertion message. Revert before final commit.
-    res = subprocess.run(
-        [sys.executable, "-c",
-         "import pyarrow.lib; pyarrow.lib._asan_sanity_oob()"],
-        capture_output=True, text=True, timeout=30,
-    )
-    assert res.returncode == 0, (
-        f"ASAN caught cython-emitted heap-buffer-overflow.\n"
-        f"returncode={res.returncode}\n"
-        f"stderr:\n{res.stderr}"
-    )
-
-
-def test_asan_sanity_oob_numpy():
-    # TODO: ASAN sanity check (libarrow_python.so / numpy_convert.cc).
-    # Same pattern as test_asan_sanity_oob. Revert before final commit.
-    res = subprocess.run(
-        [sys.executable, "-c",
-         "import pyarrow.lib; pyarrow.lib._asan_sanity_oob_numpy()"],
-        capture_output=True, text=True, timeout=30,
-    )
-    assert res.returncode == 0, (
-        f"ASAN caught heap-buffer-overflow in libarrow_python.\n"
-        f"returncode={res.returncode}\n"
-        f"stderr:\n{res.stderr}"
-    )
-
-
 @pytest.mark.skipif('sys.platform != "win32"')
 def test_get_library_dirs_win32():
     assert any(os.path.exists(os.path.join(directory, 'arrow.lib'))

From 82904cbe8ec740fbba4b8a447a540a3b97e928e0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ra=C3=BAl=20Cumplido?= <raulcumplido@gmail.com>
Date: Mon, 4 May 2026 11:42:02 +0200
Subject: [PATCH 16/22] Update version to match what we use on pyproject.toml

---
 ci/pixi/asan/cpp/pixi.toml       | 3 +--
 ci/pixi/asan/python/pixi.toml    | 3 +--
 ci/pixi/default/cpp/pixi.toml    | 3 +--
 ci/pixi/default/python/pixi.toml | 3 +--
 4 files changed, 4 insertions(+), 8 deletions(-)

diff --git a/ci/pixi/asan/cpp/pixi.toml b/ci/pixi/asan/cpp/pixi.toml
index 3d2fb73c7d11..7a27e3476878 100644
--- a/ci/pixi/asan/cpp/pixi.toml
+++ b/ci/pixi/asan/cpp/pixi.toml
@@ -42,7 +42,7 @@ test = "cd $(ls -d /arrow/ci/pixi/asan/cpp/.pixi/build/work/arrow-cpp-*/work/bui
 [package]
 name = "arrow-cpp"
 # TODO: Incorporate this to the bump version script and tests
-version = "25.0.0.dev"
+version = "25.0.0a0"
 authors = ["Apache Arrow"]
 
 [package.build]
@@ -50,7 +50,6 @@ source.path = "../../../../cpp"
 
 [package.build.backend]
 name = "pixi-build-cmake"
-version = "*"
 
 [package.build.config]
 extra-args = [
diff --git a/ci/pixi/asan/python/pixi.toml b/ci/pixi/asan/python/pixi.toml
index d7fa56349252..1bed7211307d 100644
--- a/ci/pixi/asan/python/pixi.toml
+++ b/ci/pixi/asan/python/pixi.toml
@@ -46,7 +46,7 @@ test = "pytest -r s --pyargs pyarrow --timeout=180"
 [package]
 name = "pyarrow"
 # TODO: Incorporate this to the bump version script and tests
-version = "25.0.0.dev"
+version = "25.0.0a0"
 authors = ["Apache Arrow"]
 
 [package.build]
@@ -54,7 +54,6 @@ source.path = "../../../../python"
 
 [package.build.backend]
 name = "pixi-build-python"
-version = "*"
 
 [package.build.config]
 compilers = ["c", "cxx"]
diff --git a/ci/pixi/default/cpp/pixi.toml b/ci/pixi/default/cpp/pixi.toml
index a4b850034f1a..b87a231c2aff 100644
--- a/ci/pixi/default/cpp/pixi.toml
+++ b/ci/pixi/default/cpp/pixi.toml
@@ -38,7 +38,7 @@ test = "cd $(ls -d /arrow/ci/pixi/default/cpp/.pixi/build/work/arrow-cpp-*/work/
 [package]
 name = "arrow-cpp"
 # TODO: Incorporate this to the bump version script and tests
-version = "25.0.0.dev"
+version = "25.0.0a0"
 authors = ["Apache Arrow"]
 
 [package.build]
@@ -46,7 +46,6 @@ source.path = "../../../../cpp"
 
 [package.build.backend]
 name = "pixi-build-cmake"
-version = "*"
 
 [package.build.config]
 extra-args = [
diff --git a/ci/pixi/default/python/pixi.toml b/ci/pixi/default/python/pixi.toml
index 123f3deb4f69..0d9084d9e461 100644
--- a/ci/pixi/default/python/pixi.toml
+++ b/ci/pixi/default/python/pixi.toml
@@ -42,7 +42,7 @@ test = "pytest -r s --pyargs pyarrow --timeout=60"
 [package]
 name = "pyarrow"
 # TODO: Incorporate this to the bump version script and tests
-version = "25.0.0.dev"
+version = "25.0.0a0"
 authors = ["Apache Arrow"]
 
 [package.build]
@@ -50,7 +50,6 @@ source.path = "../../../../python"
 
 [package.build.backend]
 name = "pixi-build-python"
-version = "*"
 
 [package.build.config]
 compilers = ["c", "cxx"]

From 3954735114eef3150d13854d573534c7d775174d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ra=C3=BAl=20Cumplido?= <raulcumplido@gmail.com>
Date: Mon, 4 May 2026 11:48:09 +0200
Subject: [PATCH 17/22] Add pixi.toml(s) to bump versions

---
 ci/pixi/asan/cpp/pixi.toml       | 1 -
 ci/pixi/asan/python/pixi.toml    | 1 -
 ci/pixi/default/cpp/pixi.toml    | 1 -
 ci/pixi/default/python/pixi.toml | 1 -
 dev/release/utils-prepare.sh     | 8 ++++++++
 5 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/ci/pixi/asan/cpp/pixi.toml b/ci/pixi/asan/cpp/pixi.toml
index 7a27e3476878..47e7213eccb5 100644
--- a/ci/pixi/asan/cpp/pixi.toml
+++ b/ci/pixi/asan/cpp/pixi.toml
@@ -41,7 +41,6 @@ test = "cd $(ls -d /arrow/ci/pixi/asan/cpp/.pixi/build/work/arrow-cpp-*/work/bui
 
 [package]
 name = "arrow-cpp"
-# TODO: Incorporate this to the bump version script and tests
 version = "25.0.0a0"
 authors = ["Apache Arrow"]
 
diff --git a/ci/pixi/asan/python/pixi.toml b/ci/pixi/asan/python/pixi.toml
index 1bed7211307d..3d16e4a24bf4 100644
--- a/ci/pixi/asan/python/pixi.toml
+++ b/ci/pixi/asan/python/pixi.toml
@@ -45,7 +45,6 @@ test = "pytest -r s --pyargs pyarrow --timeout=180"
 
 [package]
 name = "pyarrow"
-# TODO: Incorporate this to the bump version script and tests
 version = "25.0.0a0"
 authors = ["Apache Arrow"]
 
diff --git a/ci/pixi/default/cpp/pixi.toml b/ci/pixi/default/cpp/pixi.toml
index b87a231c2aff..cbd653c93ab7 100644
--- a/ci/pixi/default/cpp/pixi.toml
+++ b/ci/pixi/default/cpp/pixi.toml
@@ -37,7 +37,6 @@ test = "cd $(ls -d /arrow/ci/pixi/default/cpp/.pixi/build/work/arrow-cpp-*/work/
                                                                                                                                                                                                                       
 [package]
 name = "arrow-cpp"
-# TODO: Incorporate this to the bump version script and tests
 version = "25.0.0a0"
 authors = ["Apache Arrow"]
 
diff --git a/ci/pixi/default/python/pixi.toml b/ci/pixi/default/python/pixi.toml
index 0d9084d9e461..5d1061cd8b01 100644
--- a/ci/pixi/default/python/pixi.toml
+++ b/ci/pixi/default/python/pixi.toml
@@ -41,7 +41,6 @@ test = "pytest -r s --pyargs pyarrow --timeout=60"
 
 [package]
 name = "pyarrow"
-# TODO: Incorporate this to the bump version script and tests
 version = "25.0.0a0"
 authors = ["Apache Arrow"]
 
diff --git a/dev/release/utils-prepare.sh b/dev/release/utils-prepare.sh
index e67439467cc2..a0ba64cff275 100644
--- a/dev/release/utils-prepare.sh
+++ b/dev/release/utils-prepare.sh
@@ -70,6 +70,14 @@ update_versions() {
   git add PKGBUILD
   popd
 
+  pushd "${ARROW_DIR}/ci/pixi"
+    sed -i.bak -E -e \
+    "s/^version = \".+\"/version = \"${python_version}\"/" \
+    */*/pixi.toml
+  rm -f */*/pixi.toml.bak
+  git add */*/pixi.toml
+  popd
+
   pushd "${ARROW_DIR}/cpp"
   sed -i.bak -E -e \
     "s/^set\(ARROW_VERSION \".+\"\)/set(ARROW_VERSION \"${version}\")/" \

From f34bcbf84d4d19730e8877b0453340bb6f89dec5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ra=C3=BAl=20Cumplido?= <raulcumplido@gmail.com>
Date: Mon, 4 May 2026 12:05:26 +0200
Subject: [PATCH 18/22] Try to fix version bump tests

---
 dev/release/post-10-bump-versions-test.rb | 28 +++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/dev/release/post-10-bump-versions-test.rb b/dev/release/post-10-bump-versions-test.rb
index aad4d7c699cb..a8d4a3168b7b 100644
--- a/dev/release/post-10-bump-versions-test.rb
+++ b/dev/release/post-10-bump-versions-test.rb
@@ -257,6 +257,34 @@ def test_version_post_tag
              "+set(PYARROW_VERSION \"#{@next_snapshot_version}\")"],
           ],
         },
+        {
+          path: "ci/pixi/asan/cpp.toml",
+          hunks: [
+            ["-version = \"#{@release_version}a0\"",
+             "+version = \"#{@next_version}a0\""],
+          ],
+        },
+        {
+          path: "ci/pixi/asan/python/pixi.toml",
+          hunks: [
+            ["-version = \"#{@release_version}a0\"",
+             "+version = \"#{@next_version}a0\""],
+          ],
+        },
+        {
+          path: "ci/pixi/default/cpp/pixi.toml",
+          hunks: [
+            ["-version = \"#{@release_version}a0\"",
+             "+version = \"#{@next_version}a0\""],
+          ],
+        },
+        {
+          path: "ci/pixi/default/python/pixi.toml",
+          hunks: [
+            ["-version = \"#{@release_version}a0\"",
+             "+version = \"#{@next_version}a0\""],
+          ],
+        },
         {
           path: "python/pyproject.toml",
           hunks: [

From a5120842d1a571f46ecc82d80c94bc26dcaef0be Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ra=C3=BAl=20Cumplido?= <raulcumplido@gmail.com>
Date: Mon, 4 May 2026 12:12:34 +0200
Subject: [PATCH 19/22] Fix wrong path :)

---
 dev/release/post-10-bump-versions-test.rb | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/dev/release/post-10-bump-versions-test.rb b/dev/release/post-10-bump-versions-test.rb
index a8d4a3168b7b..ec03f0c2b47f 100644
--- a/dev/release/post-10-bump-versions-test.rb
+++ b/dev/release/post-10-bump-versions-test.rb
@@ -258,7 +258,7 @@ def test_version_post_tag
           ],
         },
         {
-          path: "ci/pixi/asan/cpp.toml",
+          path: "ci/pixi/asan/cpp/pixi.toml",
           hunks: [
             ["-version = \"#{@release_version}a0\"",
              "+version = \"#{@next_version}a0\""],

From 7e5fdb304527c1b01090bd6d74ab08bc680ab781 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ra=C3=BAl=20Cumplido?= <raulcumplido@gmail.com>
Date: Mon, 4 May 2026 12:25:38 +0200
Subject: [PATCH 20/22] And there's a different test file

---
 dev/release/01-prepare-test.rb | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/dev/release/01-prepare-test.rb b/dev/release/01-prepare-test.rb
index 22afe6180024..77911ca27fd4 100644
--- a/dev/release/01-prepare-test.rb
+++ b/dev/release/01-prepare-test.rb
@@ -228,6 +228,34 @@ def test_version_pre_tag
            "+set(MLARROW_VERSION \"#{@release_version}\")"],
         ],
       },
+      {
+        path: "ci/pixi/asan/cpp/pixi.toml",
+        hunks: [
+          ["-version = \"#{@release_version}a0\"",
+            "+version = \"#{@release_version}\""],
+        ],
+      },
+      {
+        path: "ci/pixi/asan/python/pixi.toml",
+        hunks: [
+          ["-version = \"#{@release_version}a0\"",
+            "+version = \"#{@release_version}\""],
+        ],
+      },
+      {
+        path: "ci/pixi/default/cpp/pixi.toml",
+        hunks: [
+          ["-version = \"#{@release_version}a0\"",
+            "+version = \"#{@release_version}\""],
+        ],
+      },
+      {
+        path: "ci/pixi/default/python/pixi.toml",
+        hunks: [
+          ["-version = \"#{@release_version}a0\"",
+            "+version = \"#{@release_version}\""],
+        ],
+      },
       {
         path: "python/CMakeLists.txt",
         hunks: [

From d351eeeb7a0caa234fef8f39f8cf55e97c43728a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ra=C3=BAl=20Cumplido?= <raulcumplido@gmail.com>
Date: Mon, 4 May 2026 17:21:33 +0200
Subject: [PATCH 21/22] Add back required version for build backend and update
 regex so it does not match

---
 ci/pixi/asan/cpp/pixi.toml       | 1 +
 ci/pixi/asan/python/pixi.toml    | 1 +
 ci/pixi/default/cpp/pixi.toml    | 1 +
 ci/pixi/default/python/pixi.toml | 1 +
 dev/release/utils-prepare.sh     | 2 +-
 5 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/ci/pixi/asan/cpp/pixi.toml b/ci/pixi/asan/cpp/pixi.toml
index 47e7213eccb5..da79afa236b2 100644
--- a/ci/pixi/asan/cpp/pixi.toml
+++ b/ci/pixi/asan/cpp/pixi.toml
@@ -49,6 +49,7 @@ source.path = "../../../../cpp"
 
 [package.build.backend]
 name = "pixi-build-cmake"
+version = "*"
 
 [package.build.config]
 extra-args = [
diff --git a/ci/pixi/asan/python/pixi.toml b/ci/pixi/asan/python/pixi.toml
index 3d16e4a24bf4..011e3581e208 100644
--- a/ci/pixi/asan/python/pixi.toml
+++ b/ci/pixi/asan/python/pixi.toml
@@ -53,6 +53,7 @@ source.path = "../../../../python"
 
 [package.build.backend]
 name = "pixi-build-python"
+version = "*"
 
 [package.build.config]
 compilers = ["c", "cxx"]
diff --git a/ci/pixi/default/cpp/pixi.toml b/ci/pixi/default/cpp/pixi.toml
index cbd653c93ab7..cf5a713a4bc5 100644
--- a/ci/pixi/default/cpp/pixi.toml
+++ b/ci/pixi/default/cpp/pixi.toml
@@ -45,6 +45,7 @@ source.path = "../../../../cpp"
 
 [package.build.backend]
 name = "pixi-build-cmake"
+version = "*"
 
 [package.build.config]
 extra-args = [
diff --git a/ci/pixi/default/python/pixi.toml b/ci/pixi/default/python/pixi.toml
index 5d1061cd8b01..162377fc2b5f 100644
--- a/ci/pixi/default/python/pixi.toml
+++ b/ci/pixi/default/python/pixi.toml
@@ -49,6 +49,7 @@ source.path = "../../../../python"
 
 [package.build.backend]
 name = "pixi-build-python"
+version = "*"
 
 [package.build.config]
 compilers = ["c", "cxx"]
diff --git a/dev/release/utils-prepare.sh b/dev/release/utils-prepare.sh
index a0ba64cff275..953ff4f0b831 100644
--- a/dev/release/utils-prepare.sh
+++ b/dev/release/utils-prepare.sh
@@ -72,7 +72,7 @@ update_versions() {
 
   pushd "${ARROW_DIR}/ci/pixi"
     sed -i.bak -E -e \
-    "s/^version = \".+\"/version = \"${python_version}\"/" \
+    "s/^version = \"[0-9].*\"/version = \"${python_version}\"/" \
     */*/pixi.toml
   rm -f */*/pixi.toml.bak
   git add */*/pixi.toml

From 5115f7d375ca1957dc3358dbb6591d8e565155ef Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ra=C3=BAl=20Cumplido?= <raulcumplido@gmail.com>
Date: Tue, 5 May 2026 10:33:49 +0200
Subject: [PATCH 22/22] Comment improvements and remove stray import

---
 ci/pixi/asan/cpp/pixi.toml          |  6 +++---
 ci/pixi/default/cpp/pixi.toml       | 14 +++++++-------
 ci/pixi/default/python/pixi.toml    |  2 +-
 python/pyarrow/lib.pyx              |  1 -
 python/pyarrow/tests/test_memory.py |  6 +++---
 5 files changed, 14 insertions(+), 15 deletions(-)

diff --git a/ci/pixi/asan/cpp/pixi.toml b/ci/pixi/asan/cpp/pixi.toml
index da79afa236b2..31c83cec46da 100644
--- a/ci/pixi/asan/cpp/pixi.toml
+++ b/ci/pixi/asan/cpp/pixi.toml
@@ -36,7 +36,8 @@ binutils = "*"
 cmake = "*"
 
 [feature.test.tasks]
-# This path mangling feels extremely finicky. Investigate alternatives to make this more robust.
+# This path depends on pixi-build's internal work-directory layout.
+# Required for running C++ tests on Docker.
 test = "cd $(ls -d /arrow/ci/pixi/asan/cpp/.pixi/build/work/arrow-cpp-*/work/build | head -n 1) && ctest --output-on-failure"
 
 [package]
@@ -71,8 +72,7 @@ extra-args = [
   "-DARROW_WITH_SNAPPY=ON",
   "-DARROW_WITH_ZLIB=ON",
   "-DARROW_WITH_ZSTD=ON",
-  # libutf8proc on package-host-dependencies seems to fail.
-  # More investigation needed. In the meantime use bundled.
+  # libutf8proc on package-host-dependencies fails use Bundled.
   "-Dutf8proc_SOURCE=BUNDLED",
   "-DOPENSSL_ROOT_DIR=$PREFIX",
 ]
diff --git a/ci/pixi/default/cpp/pixi.toml b/ci/pixi/default/cpp/pixi.toml
index cf5a713a4bc5..36851a3ec047 100644
--- a/ci/pixi/default/cpp/pixi.toml
+++ b/ci/pixi/default/cpp/pixi.toml
@@ -17,24 +17,25 @@
 
 [workspace]
 channels = ["https://prefix.dev/conda-forge"]
-platforms = ["linux-64", "linux-aarch64", "osx-arm64"]
+platforms = ["linux-64"]
 preview = ["pixi-build"]
 
 [environments]
 test    = ["test"]
 
-[feature.test.activation.env]                                                                                                                                                                                       
+[feature.test.activation.env]
 ARROW_TEST_DATA = "/arrow/testing/data"
 PARQUET_TEST_DATA = "/arrow/cpp/submodules/parquet-testing/data"
 
 [feature.test.dependencies]
 binutils = "*"
 cmake = "*"
-                                                                                                                                                                                           
+
 [feature.test.tasks]
-# This path mangling feels extremely finicky. Investigate alternatives to make this more robust.
+# This path depends on pixi-build's internal work-directory layout.
+# Required for running C++ tests on Docker.
 test = "cd $(ls -d /arrow/ci/pixi/default/cpp/.pixi/build/work/arrow-cpp-*/work/build | head -n 1) && ctest --output-on-failure"
-                                                                                                                                                                                                                      
+
 [package]
 name = "arrow-cpp"
 version = "25.0.0a0"
@@ -63,8 +64,7 @@ extra-args = [
   "-DARROW_WITH_SNAPPY=ON",
   "-DARROW_WITH_ZLIB=ON",
   "-DARROW_WITH_ZSTD=ON",
-  # libutf8proc on package-host-dependencies seems to fail.
-  # More investigation needed. In the meantime use bundled.
+  # libutf8proc on package-host-dependencies fails use Bundled.
   "-Dutf8proc_SOURCE=BUNDLED",
   "-DOPENSSL_ROOT_DIR=$PREFIX",
 ]
diff --git a/ci/pixi/default/python/pixi.toml b/ci/pixi/default/python/pixi.toml
index 162377fc2b5f..268747afbd01 100644
--- a/ci/pixi/default/python/pixi.toml
+++ b/ci/pixi/default/python/pixi.toml
@@ -17,7 +17,7 @@
 
 [workspace]
 channels = ["https://prefix.dev/conda-forge"]
-platforms = ["linux-64", "linux-aarch64", "osx-arm64"]
+platforms = ["linux-64"]
 preview = ["pixi-build"]
 
 [environments]
diff --git a/python/pyarrow/lib.pyx b/python/pyarrow/lib.pyx
index 44183917b66d..7e97177a6ec0 100644
--- a/python/pyarrow/lib.pyx
+++ b/python/pyarrow/lib.pyx
@@ -29,7 +29,6 @@ import os
 import sys
 
 from cython.operator cimport dereference as deref
-from libc.stdlib cimport malloc, free
 from pyarrow.includes.libarrow cimport *
 from pyarrow.includes.libarrow_python cimport *
 from pyarrow.includes.common cimport PyObject_to_object
diff --git a/python/pyarrow/tests/test_memory.py b/python/pyarrow/tests/test_memory.py
index dc1d185b838e..7915b39a5be2 100644
--- a/python/pyarrow/tests/test_memory.py
+++ b/python/pyarrow/tests/test_memory.py
@@ -257,21 +257,21 @@ def check_debug_memory_pool_disabled(pool_factory, env_value, msg):
         assert msg in res.stderr
 
 
-# Asan test fails as we are doing an out-of-bounds write.
+# Asan test fails as we are deliberately doing an out-of-bounds write.
 @pytest.mark.noasan
 @pytest.mark.parametrize('pool_factory', supported_factories())
 def test_debug_memory_pool_none(pool_factory):
     check_debug_memory_pool_disabled(pool_factory, "none", "")
 
 
-# Asan test fails as we are doing an out-of-bounds write.
+# Asan test fails as we are deliberately doing an out-of-bounds write.
 @pytest.mark.noasan
 @pytest.mark.parametrize('pool_factory', supported_factories())
 def test_debug_memory_pool_empty(pool_factory):
     check_debug_memory_pool_disabled(pool_factory, "", "")
 
 
-# Asan test fails as we are doing an out-of-bounds write.
+# Asan test fails as we are deliberately doing an out-of-bounds write.
 @pytest.mark.noasan
 @pytest.mark.parametrize('pool_factory', supported_factories())
 def test_debug_memory_pool_unknown(pool_factory):