diff --git a/.appveyor.yml b/.appveyor.yml
index 9a1d69a6a..85445d41a 100644
--- a/.appveyor.yml
+++ b/.appveyor.yml
@@ -1,9 +1,6 @@
 version: 1.0.{build}
 image:
 - Visual Studio 2015
-branches:
-  only:
-    - will_never_exist
 test: off
 skip_branch_with_pr: true
 build:
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 91e392f81..cd6dc6afe 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -2,7 +2,7 @@ name: CI
 
 on:
   workflow_dispatch:
-  # pull_request:
+  pull_request:
   push:
     branches:
       - master
diff --git a/.github/workflows/configure.yml b/.github/workflows/configure.yml
index 0978146bf..578dba630 100644
--- a/.github/workflows/configure.yml
+++ b/.github/workflows/configure.yml
@@ -2,7 +2,7 @@ name: Config
 
 on:
   workflow_dispatch:
-  # pull_request:
+  pull_request:
   push:
     branches:
       - master
diff --git a/.github/workflows/format.yml b/.github/workflows/format.yml
index 5e8792ee0..5cebed17d 100644
--- a/.github/workflows/format.yml
+++ b/.github/workflows/format.yml
@@ -5,7 +5,7 @@ name: Format
 
 on:
   workflow_dispatch:
-  # pull_request:
+  pull_request:
   push:
     branches:
     - master
diff --git a/.github/workflows/pip.yml b/.github/workflows/pip.yml
index 970adc93b..4414a12ee 100644
--- a/.github/workflows/pip.yml
+++ b/.github/workflows/pip.yml
@@ -2,7 +2,7 @@ name: Pip
 
 on:
   workflow_dispatch:
-  # pull_request:
+  pull_request:
   push:
     branches:
     - master
diff --git a/CMakeLists.txt b/CMakeLists.txt
index ded4dad9c..fd6a02ac0 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -105,6 +105,8 @@ set(PYBIND11_HEADERS
     include/pybind11/detail/descr.h
     include/pybind11/detail/init.h
     include/pybind11/detail/internals.h
+    include/pybind11/detail/smart_holder_poc.h
+    include/pybind11/detail/smart_holder_type_casters.h
     include/pybind11/detail/typeid.h
     include/pybind11/attr.h
     include/pybind11/buffer_info.h
@@ -122,6 +124,7 @@ set(PYBIND11_HEADERS
     include/pybind11/operators.h
     include/pybind11/pybind11.h
     include/pybind11/pytypes.h
+    include/pybind11/smart_holder.h
     include/pybind11/stl.h
     include/pybind11/stl_bind.h)
 
diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index 3bfd5f1ca..a71d858df 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -101,6 +101,9 @@ set(PYBIND11_TEST_FILES
     test_callbacks.cpp
     test_chrono.cpp
     test_class.cpp
+    test_class_sh_basic.cpp
+    test_class_sh_inheritance.cpp
+    test_class_sh_unique_ptr_member.cpp
     test_constants_and_functions.cpp
     test_copy_move.cpp
     test_custom_type_casters.cpp
@@ -129,6 +132,7 @@ set(PYBIND11_TEST_FILES
     test_stl.cpp
     test_stl_binders.cpp
     test_tagbased_polymorphic.cpp
+    test_type_caster_bare_interface.cpp
     test_union.cpp
     test_virtual_functions.cpp)
 
@@ -169,6 +173,8 @@ set(PYBIND11_CROSS_MODULE_TESTS test_exceptions.py test_local_bindings.py test_s
 
 set(PYBIND11_CROSS_MODULE_GIL_TESTS test_gil_scoped.py)
 
+set(PYBIND11_CLASS_SH_MODULE_LOCAL_TESTS test_class_sh_module_local.py)
+
 # Check if Eigen is available; if not, remove from PYBIND11_TEST_FILES (but
 # keep it in PYBIND11_PYTEST_FILES, so that we get the "eigen is not installed"
 # skip message).
@@ -303,6 +309,16 @@ foreach(t ${PYBIND11_CROSS_MODULE_GIL_TESTS})
   endif()
 endforeach()
 
+foreach(t ${PYBIND11_CLASS_SH_MODULE_LOCAL_TESTS})
+  list(FIND PYBIND11_PYTEST_FILES ${t} i)
+  if(i GREATER -1)
+    list(APPEND test_targets class_sh_module_local_0)
+    list(APPEND test_targets class_sh_module_local_1)
+    list(APPEND test_targets class_sh_module_local_2)
+    break()
+  endif()
+endforeach()
+
 # Support CUDA testing by forcing the target file to compile with NVCC
 if(PYBIND11_CUDA_TESTS)
   set_property(SOURCE ${PYBIND11_TEST_FILES} PROPERTY LANGUAGE CUDA)