diff --git a/libcxx/utils/ci/buildkite-pipeline-premerge.sh b/libcxx/utils/ci/buildkite-pipeline-premerge.sh
new file mode 100755
--- /dev/null
+++ b/libcxx/utils/ci/buildkite-pipeline-premerge.sh
@@ -0,0 +1,25 @@
+#!/usr/bin/env bash
+#===----------------------------------------------------------------------===##
+#
+# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+# See https://llvm.org/LICENSE.txt for license information.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+#
+#===----------------------------------------------------------------------===##
+
+#
+# This file generates a Buildkite pipeline that triggers the libc++ CI
+# job(s) if needed.
+# See https://buildkite.com/docs/agent/v3/cli-pipeline#pipeline-format.
+#
+# Invoked by CI on pre-merge check for a commit.
+#
+
+DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
+
+if ! git diff --name-only HEAD~1 | grep -q -E "libcxx/|libcxxabi/"; then
+  # libcxx is not affected
+  exit 0
+fi
+
+cat "${DIR}/buildkite-pipeline.yml"
diff --git a/libcxx/utils/ci/buildkite-pipeline-snapshot.sh b/libcxx/utils/ci/buildkite-pipeline-snapshot.sh
new file mode 100755
--- /dev/null
+++ b/libcxx/utils/ci/buildkite-pipeline-snapshot.sh
@@ -0,0 +1,18 @@
+#!/usr/bin/env bash
+#===----------------------------------------------------------------------===##
+#
+# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+# See https://llvm.org/LICENSE.txt for license information.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+#
+#===----------------------------------------------------------------------===##
+
+#
+# This file generates a Buildkite pipeline that triggers the libc++ CI jobs.
+# See https://buildkite.com/docs/agent/v3/cli-pipeline#pipeline-format.
+#
+# Invoked by CI on full builds.
+#
+
+DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
+cat "${DIR}/buildkite-pipeline.yml"
diff --git a/libcxx/utils/ci/buildkite-pipeline.yml b/libcxx/utils/ci/buildkite-pipeline.yml
--- a/libcxx/utils/ci/buildkite-pipeline.yml
+++ b/libcxx/utils/ci/buildkite-pipeline.yml
@@ -16,81 +16,114 @@
 
 steps:
   - label: "C++03"
-    command: "set -o pipefail && libcxx/utils/ci/run-buildbot.sh generic-cxx03 | libcxx/utils/ci/phabricator-report"
+    command: "libcxx/utils/ci/run-buildbot.sh generic-cxx03"
+    artifact_paths:
+      - "**/test-results.xml"
     agents:
       queue: "libcxx-builders"
 
   - label: "C++11"
-    command: "set -o pipefail && libcxx/utils/ci/run-buildbot.sh generic-cxx11 | libcxx/utils/ci/phabricator-report"
+    command: "libcxx/utils/ci/run-buildbot.sh generic-cxx11"
+    artifact_paths:
+    - "**/test-results.xml"
     agents:
       queue: "libcxx-builders"
 
   - label: "C++14"
-    command: "set -o pipefail && libcxx/utils/ci/run-buildbot.sh generic-cxx14 | libcxx/utils/ci/phabricator-report"
+    command: "libcxx/utils/ci/run-buildbot.sh generic-cxx14"
+    artifact_paths:
+    - "**/test-results.xml"
     agents:
       queue: "libcxx-builders"
 
   - label: "C++17"
-    command: "set -o pipefail && libcxx/utils/ci/run-buildbot.sh generic-cxx17 | libcxx/utils/ci/phabricator-report"
+    command: "libcxx/utils/ci/run-buildbot.sh generic-cxx17"
+    artifact_paths:
+    - "**/test-results.xml"
     agents:
       queue: "libcxx-builders"
 
   - label: "C++20"
-    command: "set -o pipefail && libcxx/utils/ci/run-buildbot.sh generic-cxx2a | libcxx/utils/ci/phabricator-report"
+    command: "libcxx/utils/ci/run-buildbot.sh generic-cxx2a"
+    artifact_paths:
+    - "**/test-results.xml"
     agents:
       queue: "libcxx-builders"
 
   - label: "-fno-exceptions"
-    command: "set -o pipefail && libcxx/utils/ci/run-buildbot.sh generic-noexceptions | libcxx/utils/ci/phabricator-report"
+    command: "libcxx/utils/ci/run-buildbot.sh generic-noexceptions"
+    artifact_paths:
+    - "**/test-results.xml"
     agents:
       queue: "libcxx-builders"
 
   - label: "GCC/C++20"
-    command: "set -o pipefail && libcxx/utils/ci/run-buildbot.sh generic-gcc | libcxx/utils/ci/phabricator-report"
+    command: "libcxx/utils/ci/run-buildbot.sh generic-gcc"
+    artifact_paths:
+    - "**/test-results.xml"
     agents:
       queue: "libcxx-builders"
 
   - label: "ASAN"
-    command: "set -o pipefail && libcxx/utils/ci/run-buildbot.sh generic-asan | libcxx/utils/ci/phabricator-report"
+    command: "libcxx/utils/ci/run-buildbot.sh generic-asan"
+    artifact_paths:
+    - "**/test-results.xml"
     agents:
       queue: "libcxx-builders"
 
   - label: "TSAN"
-    command: "set -o pipefail && libcxx/utils/ci/run-buildbot.sh generic-tsan | libcxx/utils/ci/phabricator-report"
+    command: "libcxx/utils/ci/run-buildbot.sh generic-tsan"
+    artifact_paths:
+    - "**/test-results.xml"
     agents:
       queue: "libcxx-builders"
 
   - label: "UBSAN"
-    command: "set -o pipefail && libcxx/utils/ci/run-buildbot.sh generic-ubsan | libcxx/utils/ci/phabricator-report"
+    command: "libcxx/utils/ci/run-buildbot.sh generic-ubsan"
+    artifact_paths:
+    - "**/test-results.xml"
     agents:
       queue: "libcxx-builders"
 
   - label: "With LLVM's libunwind"
-    command: "set -o pipefail && libcxx/utils/ci/run-buildbot.sh generic-with_llvm_unwinder | libcxx/utils/ci/phabricator-report"
+    command: "libcxx/utils/ci/run-buildbot.sh generic-with_llvm_unwinder"
+    artifact_paths:
+    - "**/test-results.xml"
     agents:
       queue: "libcxx-builders"
 
   - label: "Single-threaded"
-    command: "set -o pipefail && libcxx/utils/ci/run-buildbot.sh generic-singlethreaded | libcxx/utils/ci/phabricator-report"
+    command: "libcxx/utils/ci/run-buildbot.sh generic-singlethreaded"
+    artifact_paths:
+    - "**/test-results.xml"
     agents:
       queue: "libcxx-builders"
 
   - label: "No debug mode"
-    command: "set -o pipefail && libcxx/utils/ci/run-buildbot.sh generic-nodebug | libcxx/utils/ci/phabricator-report"
+    command: "libcxx/utils/ci/run-buildbot.sh generic-nodebug"
+    artifact_paths:
+    - "**/test-results.xml"
     agents:
       queue: "libcxx-builders"
 
   - label: "MacOS C++20"
-    command: "set -o pipefail && libcxx/utils/ci/run-buildbot.sh generic-cxx2a | libcxx/utils/ci/phabricator-report"
+    command: "libcxx/utils/ci/run-buildbot.sh generic-cxx2a"
+    artifact_paths:
+    - "**/test-results.xml"
     agents:
       queue: "libcxx-macos-builders"
 
   # Build with the configuration we use to generate libc++.dylib on Apple platforms
   - label: "Apple system"
-    command: "set -o pipefail && libcxx/utils/ci/run-buildbot.sh x86_64-apple-system | libcxx/utils/ci/phabricator-report"
+    command: "libcxx/utils/ci/run-buildbot.sh x86_64-apple-system"
+    artifact_paths:
+    - "**/test-results.xml"
     agents:
       queue: "libcxx-macos-builders"
+
   - label: "Apple system -fno-exceptions"
-    command: "set -o pipefail && libcxx/utils/ci/run-buildbot.sh x86_64-apple-system-noexceptions | libcxx/utils/ci/phabricator-report"
+    command: "libcxx/utils/ci/run-buildbot.sh x86_64-apple-system-noexceptions"
+    artifact_paths:
+    - "**/test-results.xml"
     agents:
       queue: "libcxx-macos-builders"
diff --git a/libcxx/utils/ci/run-buildbot.sh b/libcxx/utils/ci/run-buildbot.sh
--- a/libcxx/utils/ci/run-buildbot.sh
+++ b/libcxx/utils/ci/run-buildbot.sh
@@ -21,43 +21,43 @@
 generic-cxx03)
     export CC=clang
     export CXX=clang++
-    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported")
+    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported --xunit-xml-output test-results.xml")
     args+=("-C${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-cxx03.cmake")
 ;;
 generic-cxx11)
     export CC=clang
     export CXX=clang++
-    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported")
+    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported --xunit-xml-output test-results.xml")
     args+=("-C${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-cxx11.cmake")
 ;;
 generic-cxx14)
     export CC=clang
     export CXX=clang++
-    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported")
+    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported --xunit-xml-output test-results.xml")
     args+=("-C${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-cxx14.cmake")
 ;;
 generic-cxx17)
     export CC=clang
     export CXX=clang++
-    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported")
+    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported --xunit-xml-output test-results.xml")
     args+=("-C${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-cxx17.cmake")
 ;;
 generic-cxx2a)
     export CC=clang
     export CXX=clang++
-    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported")
+    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported --xunit-xml-output test-results.xml")
     args+=("-C${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-cxx2a.cmake")
 ;;
 generic-noexceptions)
     export CC=clang
     export CXX=clang++
-    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported")
+    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported --xunit-xml-output test-results.xml")
     args+=("-C${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-noexceptions.cmake")
 ;;
 generic-32bit)
     export CC=clang
     export CXX=clang++
-    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported")
+    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported --xunit-xml-output test-results.xml")
     args+=("-C${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-32bits.cmake")
 ;;
 generic-gcc)
@@ -65,60 +65,60 @@
     export CXX=g++
     # FIXME: Re-enable experimental testing on GCC. GCC cares about the order
     #        in which we link -lc++experimental, which causes issues.
-    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported --param enable_experimental=False")
+    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported --param enable_experimental=False --xunit-xml-output test-results.xml")
 ;;
 generic-asan)
     export CC=clang
     export CXX=clang++
-    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported")
+    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported --xunit-xml-output test-results.xml")
     args+=("-C${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-asan.cmake")
 ;;
 generic-msan)
     export CC=clang
     export CXX=clang++
-    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported")
+    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported --xunit-xml-output test-results.xml")
     args+=("-C${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-msan.cmake")
 ;;
 generic-tsan)
     export CC=clang
     export CXX=clang++
-    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported")
+    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported --xunit-xml-output test-results.xml")
     args+=("-C${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-tsan.cmake")
 ;;
 generic-ubsan)
     export CC=clang
     export CXX=clang++
-    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported")
+    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported --xunit-xml-output test-results.xml")
     args+=("-C${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-ubsan.cmake")
 ;;
 generic-with_llvm_unwinder)
     export CC=clang
     export CXX=clang++
-    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported")
+    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported --xunit-xml-output test-results.xml")
     args+=("-DLIBCXXABI_USE_LLVM_UNWINDER=ON")
 ;;
 generic-singlethreaded)
     export CC=clang
     export CXX=clang++
-    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported")
+    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported --xunit-xml-output test-results.xml")
     args+=("-C${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-singlethreaded.cmake")
 ;;
 generic-nodebug)
     export CC=clang
     export CXX=clang++
-    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported")
+    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported --xunit-xml-output test-results.xml")
     args+=("-C${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-nodebug.cmake")
 ;;
 x86_64-apple-system)
     export CC=clang
     export CXX=clang++
-    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported")
+    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported --xunit-xml-output test-results.xml")
     args+=("-C${MONOREPO_ROOT}/libcxx/cmake/caches/Apple.cmake")
 ;;
 x86_64-apple-system-noexceptions)
     export CC=clang
     export CXX=clang++
-    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported")
+    args+=("-DLLVM_LIT_ARGS=-sv --show-unsupported --xunit-xml-output test-results.xml")
     args+=("-C${MONOREPO_ROOT}/libcxx/cmake/caches/Apple.cmake")
     args+=("-DLIBCXX_ENABLE_EXCEPTIONS=OFF")
     args+=("-DLIBCXXABI_ENABLE_EXCEPTIONS=OFF")