@@ -3,15 +3,17 @@
 #
 # The OneBranch conda-build pipeline is `trigger: none` / `pr: none`, so its blocking
 # audit never runs on a PR. This lightweight GitHub Actions job builds ONE real
-# linux-64 conda package from the SHIPPED PyPI wheels and runs
+# linux-64 conda package from the current published PyPI wheels and runs
 # python -m eng.conda_tools elf on it, so a regression in the $ORIGIN climb,
 # the declared conda deps (krb5/libtool/openssl), or the expected DT_NEEDED set fails
 # the PR automatically -- the full-agent runtime masking cannot hide it.
 #
 # build.sh ALWAYS stamps the relative $ORIGIN climb onto the vendored Linux ODBC .so
 # (they are not code-signed, so the patch breaks no signature; an already-baked climb
 # is a byte-for-byte no-op). This gate builds one real linux-64 conda package from the
-# shipped PyPI wheels and audits the resulting climb (see conda/mssql-python/build.sh).
+# published wheels and audits the resulting climb (see conda/mssql-python/build.sh).
+# It is a published CPython 3.11 packaging control, not current-source RS/3.15
+# qualification; source-only tests above it remain current-checkout and blocking.
 #
 # PR triggers are conda-specific: general package/version changes and shared wheel
 # build infrastructure do not run this gate unless the PR also changes a path below.
@@ -72,15 +74,15 @@ jobs:
                            tests/test_038_conda_archive_limits.py \
                            tests/test_027_conda_release_metadata.py -q
 
-      - name: Fetch the shipped linux wheels from PyPI
+      - name: Fetch the published CPython 3.11 smoke wheels from PyPI
         id: public-wheels
         working-directory: ${{ github.workspace }}
         run: |
           set -euo pipefail
-          # Exact maintained release versions and PyPI digests, never an older/latest fallback.
-          # Fetch RS only if binding METADATA requires it, using its distribution (not NuGet) pin.
-          # Embedded-core public wheels are historical controls, not current-source RS proof.
+          # Select PyPI's current binding and its exact ODBC/RS dependencies, not source pins.
+          # Verify PyPI hashes and actual METADATA/WHEEL/RECORD; no older-release fallback.
           python -m eng.conda_tools fetch-wheels \
+            --published-smoke \
             --wheel-dir "$PWD/wheels" --requirements-file "$PWD/wheel-inputs.txt" \
             --python-tag cp311 --conda-subdir linux-64
           echo "Downloaded:"; ls -1 wheels
@@ -91,10 +93,9 @@ jobs:
           RS_REQUIRED: ${{ steps.public-wheels.outputs.rsRequired }}
         run: |
           set -euo pipefail
-          # The verified public dependency/ownership facts select the actual input set.
           rsArgs=()
           if [[ "$RS_REQUIRED" == "true" ]]; then
-            rsArgs=(--rs-wheel-dir "$PWD/wheels" --rs-version-file "$PWD/eng/versions/mssql-python-rs.version")
+            rsArgs=(--rs-wheel-dir "$PWD/wheels")
           elif [[ "$RS_REQUIRED" != "false" ]]; then
             echo "Missing verified public wheel profile"; exit 1
           fi
 
@@ -35,12 +35,11 @@ parameters:
       - 'Official'
       - 'NonOfficial'
     default: 'NonOfficial'
-  # Python versions to build conda packages for (Windows loops these; the POSIX legs
-  # auto-detect the same set from the downloaded wheels).
+  # Ordinary CPython versions passed explicitly to the Windows and POSIX build legs.
   - name: pythonVersions
     displayName: 'Python versions (comma-separated)'
     type: string
-    default: '3.10,3.11,3.12,3.13,3.14'
+    default: '3.10,3.11,3.12,3.13,3.14,3.15'
   # H1: enable the minimal-base ldd reachability gate (CONDA_ASSERT_PREFIX_REACHABLE).
   # It fails CLOSED if the driver binds a system (or absent) krb5/gssapi/libltdl, so it
   # is only valid on a leg with NO system copies of those libs -- set true ONLY when
@@ -198,14 +197,14 @@ extends:
               # internally (so a broken/wrong-arch package is never staged), AND win-arm64 is in
               # the release gate's requiredSubdirs -- so a MISSING win-arm64 blocks the RELEASE.
               # Net: a win-arm64 failure isolates to win-arm64 (win-64 still ships) yet still
-              # blocks the publish via the gate. DELIBERATELY a FIXED set (3.12-3.14), INDEPENDENT
+              # blocks the publish via the gate. DELIBERATELY a FIXED set (3.12-3.15), INDEPENDENT
               # of the pythonVersions parameter: neither defaults nor conda-forge ships a
               # win-arm64 python for 3.10/3.11, so following the param would queue an unbuildable
               # 3.10/3.11 arm leg. Its own bld tree + subdir-scoped verify env keep it from
               # colliding with win-64 on this shared agent.
               - template: /OneBranchPipelines/steps/conda-build-validate-step.yml@self
                 parameters:
-                  pythonVersion: '3.12,3.13,3.14'
+                  pythonVersion: '3.12,3.13,3.14,3.15'
                   condaSubdir: 'win-arm64'
                   condaTargetSubdir: 'win-arm64'
                   odbcWheelDir: '$(Pipeline.Workspace)/odbc_wheels'
 
@@ -12,15 +12,15 @@
 # Expected packages (validated conda subdirs). The self-contained mssql-python
 # package (which vendors the ODBC payload) is emitted per-Python by each build leg;
 # there is NO separate companion package:
-#   win-64        : 5 py x mssql-python                                       = 5
-#   win-arm64     : 3 py x mssql-python  (py3.12-3.14, cross-built on x64)    = 3
-#   osx-64        : 5 py x mssql-python  (Intel Mac, native)                  = 5
-#   osx-arm64     : 5 py x mssql-python  (Intel Mac, cross-built)             = 5
-#   linux-64      : 5 py x mssql-python  (glibc x86_64 host, native)          = 5
-#   linux-aarch64 : 5 py x mssql-python  (x86_64 host + QEMU, best-effort)    = 5
+#   win-64        : 6 py x mssql-python  (py3.10-3.15)                      = 6
+#   win-arm64     : 4 py x mssql-python  (py3.12-3.15, cross-built on x64)   = 4
+#   osx-64        : 6 py x mssql-python  (Intel Mac, native)                = 6
+#   osx-arm64     : 6 py x mssql-python  (Intel Mac, cross-built)            = 6
+#   linux-64      : 6 py x mssql-python  (glibc x86_64 host, native)         = 6
+#   linux-aarch64 : 6 py x mssql-python  (x86_64 host + QEMU, best-effort)   = 6
 #   ------------------------------------------------------------------------------
-#   TOTAL (PyPI parity minus musllinux)                                      = 28
-# win-arm64 is cross-built for py3.12-3.14 only (py3.10/3.11 have no win-arm64 deps
+#   TOTAL (ordinary CPython, no musllinux or free-threaded variants)           = 34
+# win-arm64 is cross-built for py3.12-3.15 only (py3.10/3.11 have no win-arm64 deps
 # on Anaconda defaults); its runtime import is skipped on the x64 host, so its arch
 # is enforced by the PE audit (eng.conda_tools pe). musllinux (no conda
 # musl subdir) is intentionally NOT conda-built. This job is BEST-EFFORT and never
@@ -117,7 +117,7 @@ jobs:
             n=$(find "$d" -type f \( -name '*.conda' -o -name '*.tar.bz2' \) | wc -l)
             printf '  %-14s %s\n' "$sub" "$n"
           done
-          echo "Total conda package count: $PKG_COUNT (full PyPI-parity set = 28)"
+          echo "Total conda package count: $PKG_COUNT (full ordinary-CPython set = 34)"
 
           # BEST-EFFORT: never exit non-zero — an empty set emits a warning; a partial set
           # remains visible in the counts above. A conda hiccup must not block the wheel
 
@@ -27,7 +27,7 @@
 parameters:
   # Python version(s) to build, comma-separated X.Y (e.g. '3.13' or '3.12,3.13,3.14'); passed
   # straight to the orchestrator's --python-versions. win-64 follows the pythonVersions
-  # parameter; win-arm64 uses a fixed 3.12-3.14 set (the singular name is kept for callers).
+  # parameter; win-arm64 uses a fixed 3.12-3.15 set (the singular name is kept for callers).
   - name: pythonVersion
     type: string
   # Conda subdir for this leg's package metadata + staging: 'win-64' (native) or 'win-arm64'
 
@@ -68,7 +68,7 @@ parameters:
   # against this job's independently downloaded artifact before upload.
   - name: pythonVersions
     type: string
-    default: '3.10,3.11,3.12,3.13,3.14'
+    default: '3.10,3.11,3.12,3.13,3.14,3.15'
   # The publisher hash lock targets CPython 3.12 / Windows x64; other runtimes reject.
   - name: pythonVersion
     type: string
 
@@ -35,7 +35,7 @@
 # dependency solve PLUS a PE machine-type assert on the vendored arm64 .pyd/.dll, so a
 # broken or wrong-arch package is never STAGED. That build leg is continueOnError (so a
 # win-arm64 hiccup can't nuke the shared win-64 publish), and THIS release gate is where
-# win-arm64 is enforced: a missing win-arm64 fails the gate. Its matrix is 3.12-3.14 (the
+# win-arm64 is enforced: a missing win-arm64 fails the gate. Its matrix is 3.12-3.15 (the
 # gate's per-subdir override), since Anaconda `defaults` has no win-arm64 python for
 # 3.10/3.11. musllinux has no conda subdir at all (conda Linux is glibc-only), so absent.
 #
@@ -64,7 +64,7 @@ parameters:
   # subdir. The gate reads each binding's pyXY build tag from info/index.json.
   - name: pythonVersions
     type: string
-    default: '3.10,3.11,3.12,3.13,3.14'
+    default: '3.10,3.11,3.12,3.13,3.14,3.15'
   # Optional EXACT expected versions. When set, the gate asserts every package's
   # info/index.json version matches; when empty it still enforces one-version-per-
   # package consistency plus the subdir / matrix / pairing checks.
 
@@ -57,8 +57,15 @@ The `conda-audit` PR gate triggers only for `conda/`, `eng/conda_tools/`, Conda-
 OneBranch pipelines/steps/jobs, their native/probe/archive/provenance and release tests,
 and the workflow itself. General package metadata/version changes and shared wheel-build
 infrastructure do not trigger it on their own; mixed PRs with a Conda change still do.
-This scope does not change the unit-test runner, source-version wheel selection, or
-failure handling when a required wheel is unpublished.
+Source-only tests remain current-checkout and blocking. The real Linux CPython 3.11
+build/audit uses `fetch-wheels --published-smoke`: PyPI's current published binding
+and its exact ODBC dependency (plus RS when required). No smoke versions or hashes
+are hardcoded; downloads are verified against PyPI's SHA256 values and actual wheel
+metadata/ownership. Source release bumps do not select unpublished smoke inputs.
+The selected versions are logged and hash-required requirements are generated per run.
+Missing wheels, metadata/dependency or hash mismatches and build/audit failures still
+fail the gate; there is no skip or older-release fallback. This published packaging
+control does not qualify current-source RS or Python 3.15.
 
 Run the source-only trigger regressions without a native build, SQL Server, or PyYAML:
 
@@ -112,8 +119,9 @@ macOS retains its external Homebrew/MacPorts OpenSSL prerequisite for encryption
 Conda OpenSSL alone does not satisfy the driver's system-path lookup.
 
 The release goal is the matching PyPI release's public API and supported feature
-behavior on all 28 ordinary CPython variants: 3.10-3.14 on win-64, linux-64,
-linux-aarch64, osx-64 and osx-arm64; 3.12-3.14 on win-arm64. No silent removal of
+behavior on all 34 ordinary CPython variants: 3.10-3.15 on win-64, linux-64,
+linux-aarch64, osx-64 and osx-arm64; 3.12-3.15 on win-arm64. Free-threaded CPython
+(including `cp315t`) and musllinux are not Conda targets. No silent removal of
 required native functionality is acceptable. Optional features require their
 corresponding dependencies; Windows ARM64 PyArrow availability remains a blocker
 to qualifying those features, not permission to drop them.
@@ -125,7 +133,7 @@ load do not establish those results. Applicable OS, certificate and authenticati
 configuration remain external prerequisites.
 
 Use only organizationally approved channels and handle applicable terms separately;
-the Windows ARM64 dependency profile includes Anaconda `defaults`. Before unattended
+the Windows ARM64 3.12-3.14 dependency profile includes Anaconda `defaults`. Before unattended
 Windows ARM64 builds, agent owners must use approved provisioning to put a disposable
 Conda installation on `PATH`, with applicable channel terms handled for the job's
 execution identity. The orchestrator's automatic Miniforge installation does not
@@ -134,6 +142,25 @@ or verification solve stops with Conda's diagnostic; provision the prerequisite
 running again. Automatic acceptance, including an inherited
 `CONDA_PLUGINS_AUTO_ACCEPT_TOS` opt-in, remains disabled.
 
+Windows ARM64 3.15 uses `microsoft`, then `conda-forge`, for both build and verification
+(after the local verification channel), without `defaults`. Older targets retain their
+existing channel policies and the ARM64 3.12 manual ABI pin. The blocking full dependency
+solve remains; every 3.15 package must pass the `python_abi 3.15.* *_cp315` native audit.
+
+### Python 3.15 packaging
+
+Conda-forge's Windows Python 3.15 declares `lib/python/site-packages` instead of
+`Lib/site-packages` ([layout change](https://conda-forge.org/blog/2026/09/03/python-315/)).
+The Windows recipe uses the target's `SP_DIR` for binding/RS/ODBC extraction, with
+matching native and installed-metadata checks. Windows legs containing 3.15 use
+**conda-build 26.9.1** for all requested variants: its
+[26.9.0 fix](https://github.com/conda/conda-build/releases/tag/26.9.0) reads
+`python_site_packages_path` from the target Python record, including cross builds.
+25.x computes the old Windows path even for 3.15. Other legs retain `conda-build<26`;
+the publishing toolchain is unchanged. The existing RS 0.3.0 stable-ABI selection and
+ODBC `py3-none` wheels need no version change. PyArrow stays optional; no speculative
+`libpython` dependency or change to the Unix OS floors is introduced.
+
 Run this existing build workflow only in a disposable isolated installation: shared-environment
 ownership hardening is outside this change. Publication/provenance tooling is included
 alongside this native/tooling foundation; see the
@@ -262,17 +289,19 @@ members. This detects unowned or cross-owned additions; it cannot recover file o
 after an overwrite of an already owned path, which is why the raw pre-extraction gate
 is required.
 
-`fetch-wheels` uses exact current maintained versions, hash-required binary-only PyPI
+By default, `fetch-wheels` uses exact current maintained versions, hash-required binary-only PyPI
 downloads, and actual wheel metadata/ownership. Pip selects for its executing interpreter;
 the requested Python/platform must match the binding, ODBC and selected RS wheel tags
 before the command accepts the inputs. These arguments validate the download, rather
 than enabling cross-target pip resolution. An authentic published embedded-core
 binding is explicitly reported as a **historical published packaging control, not
 current-source RS qualification**. An RS-dependent published binding requires its exact
-provider and source pin; unavailable releases, malformed declarations, or mismatches
+provider and selected pin; unavailable releases, malformed declarations, or mismatches
 fail with no older-version or TLS fallback. Public availability does not gate the
 recorded ADO artifact path. Neither a public input check nor static archive checks
 establish installed SQL/runtime qualification.
+Only the explicit `--published-smoke` option selects the published inputs above;
+production, provenance, preflight and release/publish version selection are unchanged.
 
 The driver-load probe's sole implementation is
 `eng/conda_tools/driver_load_probe.py`. It separates native connection execution,
 
@@ -4,7 +4,13 @@ REM vendor the ODBC Driver 18 payload inside it. conda-build exports PKG_NAME /
 REM PKG_VERSION / CONDA_PY; the pipeline exports WHEELS_DIR + MSSQL_ODBC_VERSION.
 setlocal enabledelayedexpansion
 
-set "SP=%PREFIX%\Lib\site-packages"
+REM conda-build 26.9+ reads the target Python's python_site_packages_path (CFEP-27).
+REM Python 3.15 uses lib\python\site-packages; older Windows targets use Lib\site-packages.
+if not defined SP_DIR (
+  echo ERROR: conda-build must supply the target Python site-packages in SP_DIR.
+  exit /b 1
+)
+set "SP=%SP_DIR%"
 if not exist "%SP%" mkdir "%SP%"
 set "PKG_UNDERSCORE=%PKG_NAME:-=_%"
 
 
@@ -36,7 +36,7 @@ requirements:
     # --python matrix here, so each build emits the matching py3XX package. A range such
     # as `python >=3.10` collapses ALL --python builds into ONE cp<newest> package (build
     # string "py>=310") whose python_abi is pinned to 3.14, so `conda create python=3.10
-    # mssql-python` can't solve. The >=3.10 floor is enforced implicitly: only py310-py314
+    # mssql-python` can't solve. The >=3.10 floor is enforced implicitly: only py310-py315
     # are built and each package's python_abi pins its exact minor.
     - python
     - pip
 
@@ -302,10 +302,10 @@ def build_packages(
     croot = os.path.join(os.path.dirname(os.path.abspath(bld)), "croot")
     if os.path.isdir(croot):
         shutil.rmtree(croot)
-    channels = ["microsoft", "conda-forge"]
-    if target_subdir == "win-arm64":
-        channels.insert(0, "defaults")
     for py in pyvers:
+        channels = ["microsoft", "conda-forge"]
+        if target_subdir == "win-arm64" and py != "3.15":
+            channels.insert(0, "defaults")
         environment._log(
             f"=== [py {py}] build mssql-python (self-contained: vendors the ODBC payload) ==="
         )
@@ -471,8 +471,8 @@ def execute(args: argparse.Namespace) -> int:
     conda = environment.find_or_install_conda(output_dir)
     environment._log(f"Using conda: {conda}")
     environment.run([conda, "--version"], what="conda --version")
-    builder = environment.create_builder_env(conda)
     pyvers = detect_pythons(links, python_versions)
+    builder = environment.create_builder_env(conda, target, pyvers)
     cross_build = bool(args.conda_target_subdir)
     env = environment.build_env(mssql_ver, odbc_ver, links, args.conda_target_subdir, rs_ver)