diff --git a/tools/internal_ci/helper_scripts/prepare_build_windows.bat b/tools/internal_ci/helper_scripts/prepare_build_windows.bat
index 1634acd389dfb855ac716fd9a58ce568cd2ac1f2..643eb380e8776df436ff6c32bd10af4ad3b4824a 100644
--- a/tools/internal_ci/helper_scripts/prepare_build_windows.bat
+++ b/tools/internal_ci/helper_scripts/prepare_build_windows.bat
@@ -18,4 +18,7 @@ set PATH=C:\tools\msys64\usr\bin;C:\Python27;%PATH%
 
 bash tools/internal_ci/helper_scripts/gen_report_index.sh
 
+@rem Needed for big_query_utils
+python -m pip install google-api-python-client
+
 git submodule update --init
diff --git a/tools/internal_ci/linux/pull_request/grpc_basictests_c_cpp_dbg.cfg b/tools/internal_ci/linux/pull_request/grpc_basictests_c_cpp_dbg.cfg
new file mode 100644
index 0000000000000000000000000000000000000000..dcc6265b34ca4e42700dbb35376b024298e734f8
--- /dev/null
+++ b/tools/internal_ci/linux/pull_request/grpc_basictests_c_cpp_dbg.cfg
@@ -0,0 +1,30 @@
+# Copyright 2017 gRPC authors.
+#
+# Licensed 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.
+
+# Config file for the internal CI (in protobuf text format)
+
+# Location of the continuous shell script in repository.
+build_file: "grpc/tools/internal_ci/linux/grpc_run_tests_matrix.sh"
+timeout_mins: 240
+action {
+  define_artifacts {
+    regex: "**/*sponge_log.xml"
+    regex: "github/grpc/reports/**"
+  }
+}
+
+env_vars {
+  key: "RUN_TESTS_FLAGS"
+  value: "-f basictests linux corelang dbg --inner_jobs 16 -j 1 --internal_ci"
+}
diff --git a/tools/internal_ci/linux/pull_request/grpc_basictests_c_cpp_opt.cfg b/tools/internal_ci/linux/pull_request/grpc_basictests_c_cpp_opt.cfg
new file mode 100644
index 0000000000000000000000000000000000000000..f60beaf15c1820b52761276e0741bfa156e4d4c5
--- /dev/null
+++ b/tools/internal_ci/linux/pull_request/grpc_basictests_c_cpp_opt.cfg
@@ -0,0 +1,30 @@
+# Copyright 2017 gRPC authors.
+#
+# Licensed 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.
+
+# Config file for the internal CI (in protobuf text format)
+
+# Location of the continuous shell script in repository.
+build_file: "grpc/tools/internal_ci/linux/grpc_run_tests_matrix.sh"
+timeout_mins: 240
+action {
+  define_artifacts {
+    regex: "**/*sponge_log.xml"
+    regex: "github/grpc/reports/**"
+  }
+}
+
+env_vars {
+  key: "RUN_TESTS_FLAGS"
+  value: "-f basictests linux corelang opt --inner_jobs 16 -j 1 --internal_ci"
+}
diff --git a/tools/internal_ci/macos/grpc_master.cfg b/tools/internal_ci/linux/pull_request/grpc_basictests_multilang.cfg
similarity index 86%
rename from tools/internal_ci/macos/grpc_master.cfg
rename to tools/internal_ci/linux/pull_request/grpc_basictests_multilang.cfg
index ce3609c9ec47923feb0032087f5a1490b7315d50..7c16cf6a10a2b20ee4dd0045fba10804cdb04093 100644
--- a/tools/internal_ci/macos/grpc_master.cfg
+++ b/tools/internal_ci/linux/pull_request/grpc_basictests_multilang.cfg
@@ -15,7 +15,7 @@
 # Config file for the internal CI (in protobuf text format)
 
 # Location of the continuous shell script in repository.
-build_file: "grpc/tools/internal_ci/macos/grpc_run_tests_matrix.sh"
+build_file: "grpc/tools/internal_ci/linux/grpc_run_tests_matrix.sh"
 timeout_mins: 240
 action {
   define_artifacts {
@@ -26,5 +26,5 @@ action {
 
 env_vars {
   key: "RUN_TESTS_FLAGS"
-  value: "-f basictests macos --internal_ci -j 2 --inner_jobs 4"
+  value: "-f basictests linux multilang --inner_jobs 16 -j 2 --internal_ci"
 }
diff --git a/tools/internal_ci/windows/grpc_portability.cfg b/tools/internal_ci/windows/grpc_portability.cfg
new file mode 100644
index 0000000000000000000000000000000000000000..c395cb4a9499b8e3092273582137373043e32160
--- /dev/null
+++ b/tools/internal_ci/windows/grpc_portability.cfg
@@ -0,0 +1,30 @@
+# Copyright 2017 gRPC authors.
+#
+# Licensed 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.
+
+# Config file for the internal CI (in protobuf text format)
+
+# Location of the continuous shell script in repository.
+build_file: "grpc/tools/internal_ci/windows/grpc_run_tests_matrix.bat"
+timeout_mins: 360
+action {
+  define_artifacts {
+    regex: "**/*sponge_log.xml"
+    regex: "github/grpc/reports/**"
+  }
+}
+
+env_vars {
+  key: "RUN_TESTS_FLAGS"
+  value: "-f portability windows -j 1 --inner_jobs 8 --internal_ci"
+}
diff --git a/tools/internal_ci/windows/grpc_master.cfg b/tools/internal_ci/windows/pull_request/grpc_basictests.cfg
similarity index 100%
rename from tools/internal_ci/windows/grpc_master.cfg
rename to tools/internal_ci/windows/pull_request/grpc_basictests.cfg
diff --git a/tools/internal_ci/windows/pull_request/grpc_portability.cfg b/tools/internal_ci/windows/pull_request/grpc_portability.cfg
new file mode 100644
index 0000000000000000000000000000000000000000..c395cb4a9499b8e3092273582137373043e32160
--- /dev/null
+++ b/tools/internal_ci/windows/pull_request/grpc_portability.cfg
@@ -0,0 +1,30 @@
+# Copyright 2017 gRPC authors.
+#
+# Licensed 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.
+
+# Config file for the internal CI (in protobuf text format)
+
+# Location of the continuous shell script in repository.
+build_file: "grpc/tools/internal_ci/windows/grpc_run_tests_matrix.bat"
+timeout_mins: 360
+action {
+  define_artifacts {
+    regex: "**/*sponge_log.xml"
+    regex: "github/grpc/reports/**"
+  }
+}
+
+env_vars {
+  key: "RUN_TESTS_FLAGS"
+  value: "-f portability windows -j 1 --inner_jobs 8 --internal_ci"
+}