diff --git a/.gitmodules b/.gitmodules
index 4dbf077..e69de29 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,3 +0,0 @@
-[submodule "python/pybind11"]
-	path = python/pybind11
-	url = https://github.com/pybind/pybind11
diff --git a/common/include/common_defs.hpp b/common/include/common_defs.hpp
index 778f851..dadcaac 100644
--- a/common/include/common_defs.hpp
+++ b/common/include/common_defs.hpp
@@ -29,6 +29,8 @@
 
 static const uint64_t DEFAULT_SEED = 9001;
 
+enum resize_factor { X1 = 0, X2, X4, X8 };
+
 template<typename A> using AllocChar = typename std::allocator_traits<A>::template rebind_alloc<char>;
 template<typename A> using string = std::basic_string<char, std::char_traits<char>, AllocChar<A>>;
 
diff --git a/cpc/include/cpc_common.hpp b/cpc/include/cpc_common.hpp
index cde110f..feb1e15 100644
--- a/cpc/include/cpc_common.hpp
+++ b/cpc/include/cpc_common.hpp
@@ -26,9 +26,16 @@
 
 namespace datasketches {
 
-static const uint8_t CPC_MIN_LG_K = 4;
-static const uint8_t CPC_MAX_LG_K = 26;
-static const uint8_t CPC_DEFAULT_LG_K = 11;
+namespace cpc_constants {
+    const uint8_t MIN_LG_K = 4;
+    const uint8_t MAX_LG_K = 26;
+    const uint8_t DEFAULT_LG_K = 11;
+}
+
+// TODO: Redundant and deprecated. Will be removed in next major version release.
+static const uint8_t CPC_MIN_LG_K = cpc_constants::MIN_LG_K;
+static const uint8_t CPC_MAX_LG_K = cpc_constants::MAX_LG_K;
+static const uint8_t CPC_DEFAULT_LG_K = cpc_constants::DEFAULT_LG_K;
 
 template<typename A> using AllocU8 = typename std::allocator_traits<A>::template rebind_alloc<uint8_t>;
 template<typename A> using AllocU16 = typename std::allocator_traits<A>::template rebind_alloc<uint16_t>;
diff --git a/cpc/include/cpc_sketch.hpp b/cpc/include/cpc_sketch.hpp
index cdc4d16..c000ac9 100644
--- a/cpc/include/cpc_sketch.hpp
+++ b/cpc/include/cpc_sketch.hpp
@@ -67,7 +67,7 @@
    * @param lg_k base 2 logarithm of the number of bins in the sketch
    * @param seed for hash function
    */
-  explicit cpc_sketch_alloc(uint8_t lg_k = CPC_DEFAULT_LG_K, uint64_t seed = DEFAULT_SEED, const A& allocator = A());
+  explicit cpc_sketch_alloc(uint8_t lg_k = cpc_constants::DEFAULT_LG_K, uint64_t seed = DEFAULT_SEED, const A& allocator = A());
 
   using allocator_type = A;
   A get_allocator() const;
diff --git a/cpc/include/cpc_union.hpp b/cpc/include/cpc_union.hpp
index dd59abc..54fbed5 100644
--- a/cpc/include/cpc_union.hpp
+++ b/cpc/include/cpc_union.hpp
@@ -45,7 +45,7 @@
    * @param lg_k base 2 logarithm of the number of bins in the sketch
    * @param seed for hash function
    */
-  explicit cpc_union_alloc(uint8_t lg_k = CPC_DEFAULT_LG_K, uint64_t seed = DEFAULT_SEED, const A& allocator = A());
+  explicit cpc_union_alloc(uint8_t lg_k = cpc_constants::DEFAULT_LG_K, uint64_t seed = DEFAULT_SEED, const A& allocator = A());
 
   cpc_union_alloc(const cpc_union_alloc<A>& other);
   cpc_union_alloc(cpc_union_alloc<A>&& other) noexcept;
diff --git a/kll/include/kll_sketch.hpp b/kll/include/kll_sketch.hpp
index 28ea8ea..fa55520 100644
--- a/kll/include/kll_sketch.hpp
+++ b/kll/include/kll_sketch.hpp
@@ -153,6 +153,10 @@
 template<typename A> using AllocD = typename std::allocator_traits<A>::template rebind_alloc<double>;
 template<typename A> using vector_d = std::vector<double, AllocD<A>>;
 
+namespace kll_constants {
+  const uint16_t DEFAULT_K = 200;
+}
+
 template <typename T, typename C = std::less<T>, typename S = serde<T>, typename A = std::allocator<T>>
 class kll_sketch {
   public:
@@ -160,11 +164,12 @@
     using comparator = C;
 
     static const uint8_t DEFAULT_M = 8;
-    static const uint16_t DEFAULT_K = 200;
+    // TODO: Redundant and deprecated. Will be remove din next major version.
+    static const uint16_t DEFAULT_K = kll_constants::DEFAULT_K;
     static const uint16_t MIN_K = DEFAULT_M;
     static const uint16_t MAX_K = (1 << 16) - 1;
 
-    explicit kll_sketch(uint16_t k = DEFAULT_K, const A& allocator = A());
+    explicit kll_sketch(uint16_t k = kll_constants::DEFAULT_K, const A& allocator = A());
     kll_sketch(const kll_sketch& other);
     kll_sketch(kll_sketch&& other) noexcept;
     ~kll_sketch();
diff --git a/pyproject.toml b/pyproject.toml
index 077b885..a989be3 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -2,7 +2,8 @@
 requires = ["wheel",
             "setuptools >= 30.3.0",
             "setuptools_scm",
-            "cmake >= 3.12"]
+            "cmake >= 3.12",
+            "pybind11[global] >= 2.6.0"]
 
 [tool.tox]
 legacy_tox_ini = """
@@ -12,6 +13,7 @@
 [testenv]
 deps = pytest
        numpy
+       pybind11[global] >= 2.6.0
 changedir = python/tests
 commands = pytest
 """
\ No newline at end of file
diff --git a/python/CMakeLists.txt b/python/CMakeLists.txt
index 0b76799..4da7b9d 100644
--- a/python/CMakeLists.txt
+++ b/python/CMakeLists.txt
@@ -22,9 +22,12 @@
   set(PYBIND11_CPP_STANDARD -std=c++11)
 endif()
 
-add_subdirectory(pybind11)
+find_package(Python3 COMPONENTS Interpreter Development)
+find_package(pybind11 CONFIG)
+#add_subdirectory(pybind11)
 
-pybind11_add_module(python MODULE EXCLUDE_FROM_ALL SYSTEM THIN_LTO)
+#pybind11_add_module(python MODULE EXCLUDE_FROM_ALL SYSTEM THIN_LTO)
+pybind11_add_module(python MODULE EXCLUDE_FROM_ALL THIN_LTO)
 
 target_link_libraries(python
   PRIVATE
diff --git a/python/pybind11 b/python/pybind11
deleted file mode 160000
index 59a2ac2..0000000
--- a/python/pybind11
+++ /dev/null
@@ -1 +0,0 @@
-Subproject commit 59a2ac2745d8a57ac94c6accced73620d59fb844
diff --git a/python/src/cpc_wrapper.cpp b/python/src/cpc_wrapper.cpp
index 673e3c7..deae7f6 100644
--- a/python/src/cpc_wrapper.cpp
+++ b/python/src/cpc_wrapper.cpp
@@ -53,7 +53,7 @@
   using namespace datasketches;
 
   py::class_<cpc_sketch>(m, "cpc_sketch")
-    .def(py::init<uint8_t, uint64_t>(), py::arg("lg_k")=CPC_DEFAULT_LG_K, py::arg("seed")=DEFAULT_SEED)
+    .def(py::init<uint8_t, uint64_t>(), py::arg("lg_k")=cpc_constants::DEFAULT_LG_K, py::arg("seed")=DEFAULT_SEED)
     .def(py::init<const cpc_sketch&>())
     .def("__str__", &cpc_sketch::to_string,
          "Produces a string summary of the sketch")
diff --git a/python/src/kll_wrapper.cpp b/python/src/kll_wrapper.cpp
index d356358..48004b9 100644
--- a/python/src/kll_wrapper.cpp
+++ b/python/src/kll_wrapper.cpp
@@ -116,7 +116,7 @@
   using namespace datasketches;
 
   py::class_<kll_sketch<T>>(m, name)
-    .def(py::init<uint16_t>(), py::arg("k")=kll_sketch<T>::DEFAULT_K)
+    .def(py::init<uint16_t>(), py::arg("k")=kll_constants::DEFAULT_K)
     .def(py::init<const kll_sketch<T>&>())
     .def("update", (void (kll_sketch<T>::*)(const T&)) &kll_sketch<T>::update, py::arg("item"),
          "Updates the sketch with the given value")
diff --git a/python/src/theta_wrapper.cpp b/python/src/theta_wrapper.cpp
index cf8fdc7..86a2406 100644
--- a/python/src/theta_wrapper.cpp
+++ b/python/src/theta_wrapper.cpp
@@ -103,7 +103,7 @@
 
   py::class_<update_theta_sketch, theta_sketch>(m, "update_theta_sketch")
     .def(py::init(&dspy::update_theta_sketch_factory),
-         py::arg("lg_k")=update_theta_sketch::builder::DEFAULT_LG_K, py::arg("p")=1.0, py::arg("seed")=DEFAULT_SEED)
+         py::arg("lg_k")=theta_constants::DEFAULT_LG_K, py::arg("p")=1.0, py::arg("seed")=DEFAULT_SEED)
     .def(py::init<const update_theta_sketch&>())
     .def("update", (void (update_theta_sketch::*)(int64_t)) &update_theta_sketch::update, py::arg("datum"),
          "Updates the sketch with the given integral value")
@@ -127,7 +127,7 @@
 
   py::class_<theta_union>(m, "theta_union")
     .def(py::init(&dspy::theta_union_factory),
-         py::arg("lg_k")=update_theta_sketch::builder::DEFAULT_LG_K, py::arg("p")=1.0, py::arg("seed")=DEFAULT_SEED)
+         py::arg("lg_k")=theta_constants::DEFAULT_LG_K, py::arg("p")=1.0, py::arg("seed")=DEFAULT_SEED)
     .def("update", &theta_union::update<const theta_sketch&>, py::arg("sketch"),
          "Updates the union with the given sketch")
     .def("get_result", &theta_union::get_result, py::arg("ordered")=true,
diff --git a/python/src/vector_of_kll.cpp b/python/src/vector_of_kll.cpp
index b8d8a91..5a2ef1d 100644
--- a/python/src/vector_of_kll.cpp
+++ b/python/src/vector_of_kll.cpp
@@ -29,14 +29,20 @@
 
 namespace datasketches {
 
+namespace vector_of_kll_constants {
+  static const uint32_t DEFAULT_K = kll_constants::DEFAULT_K;
+  static const uint32_t DEFAULT_D = 1;
+}
+
 // Wrapper class for Numpy compatibility
 template <typename T, typename C = std::less<T>, typename S = serde<T>>
 class vector_of_kll_sketches {
   public:
-    static const uint32_t DEFAULT_K = kll_sketch<T, C, S>::DEFAULT_K;
-    static const uint32_t DEFAULT_D = 1;
+    // TODO: Redundant and deprecated. Will be removed in next major version release.
+    static const uint32_t DEFAULT_K = vector_of_kll_constants::DEFAULT_K;
+    static const uint32_t DEFAULT_D = vector_of_kll_constants::DEFAULT_D;
 
-    explicit vector_of_kll_sketches(uint32_t k = DEFAULT_K, uint32_t d = DEFAULT_D);
+    explicit vector_of_kll_sketches(uint32_t k = vector_of_kll_constants::DEFAULT_K, uint32_t d = vector_of_kll_constants::DEFAULT_D);
     vector_of_kll_sketches(const vector_of_kll_sketches& other);
     vector_of_kll_sketches(vector_of_kll_sketches&& other) noexcept;
     vector_of_kll_sketches<T,C,S>& operator=(const vector_of_kll_sketches& other);
@@ -432,8 +438,8 @@
   using namespace datasketches;
 
   py::class_<vector_of_kll_sketches<T>>(m, name)
-    .def(py::init<uint32_t, uint32_t>(), py::arg("k")=vector_of_kll_sketches<T>::DEFAULT_K, 
-                                         py::arg("d")=vector_of_kll_sketches<T>::DEFAULT_D)
+    .def(py::init<uint32_t, uint32_t>(), py::arg("k")=vector_of_kll_constants::DEFAULT_K, 
+                                         py::arg("d")=vector_of_kll_constants::DEFAULT_D)
     .def(py::init<const vector_of_kll_sketches<T>&>())
     // allow user to retrieve k or d, in case it's instantiated w/ defaults
     .def("get_k", &vector_of_kll_sketches<T>::get_k,
diff --git a/sampling/include/var_opt_sketch.hpp b/sampling/include/var_opt_sketch.hpp
index 3f5110c..a949899 100644
--- a/sampling/include/var_opt_sketch.hpp
+++ b/sampling/include/var_opt_sketch.hpp
@@ -51,18 +51,23 @@
   double total_sketch_weight;
 };
 
-enum resize_factor { X1 = 0, X2, X4, X8 };
-
 template <typename T, typename S, typename A> class var_opt_union; // forward declaration
 
+namespace var_opt_constants {
+    const resize_factor DEFAULT_RESIZE_FACTOR = resize_factor::X8;
+    const uint32_t MAX_K = ((uint32_t) 1 << 31) - 2; 
+}
+
 template <typename T, typename S = serde<T>, typename A = std::allocator<T>>
 class var_opt_sketch {
 
   public:
-    static const resize_factor DEFAULT_RESIZE_FACTOR = X8;
-    static const uint32_t MAX_K = ((uint32_t) 1 << 31) - 2;
+    static const resize_factor DEFAULT_RESIZE_FACTOR = var_opt_constants::DEFAULT_RESIZE_FACTOR;
+    static const uint32_t MAX_K = var_opt_constants::MAX_K;
 
-    explicit var_opt_sketch(uint32_t k, resize_factor rf = DEFAULT_RESIZE_FACTOR, const A& allocator = A());
+    explicit var_opt_sketch(uint32_t k,
+      resize_factor rf = var_opt_constants::DEFAULT_RESIZE_FACTOR,
+      const A& allocator = A());
     var_opt_sketch(const var_opt_sketch& other);
     var_opt_sketch(var_opt_sketch&& other) noexcept;
 
diff --git a/sampling/include/var_opt_sketch_impl.hpp b/sampling/include/var_opt_sketch_impl.hpp
index dbfe5a4..ce0ac40 100644
--- a/sampling/include/var_opt_sketch_impl.hpp
+++ b/sampling/include/var_opt_sketch_impl.hpp
@@ -128,7 +128,7 @@
   r_(r_count),
   n_(n),
   total_wt_r_(total_wt_r),
-  rf_(DEFAULT_RESIZE_FACTOR),
+  rf_(var_opt_constants::DEFAULT_RESIZE_FACTOR),
   curr_items_alloc_(len),
   filled_data_(n > k),
   allocator_(allocator),
diff --git a/setup.py b/setup.py
index 9d270d9..a84954e 100644
--- a/setup.py
+++ b/setup.py
@@ -49,8 +49,9 @@
             os.path.dirname(self.get_ext_fullpath(ext.name)))
         cmake_args =  ['-DCMAKE_LIBRARY_OUTPUT_DIRECTORY=' + extdir]
         cmake_args += ['-DWITH_PYTHON=True']
+        cmake_args += ['-DCMAKE_CXX_STANDARD=11']
         # ensure we use a consistent python version
-        cmake_args += ['-DPYTHON_EXECUTABLE=' + sys.executable]
+        cmake_args += ['-DPython3_EXECUTABLE=' + sys.executable]
         cfg = 'Debug' if self.debug else 'Release'
         build_args = ['--config', cfg]
 
diff --git a/theta/include/theta_constants.hpp b/theta/include/theta_constants.hpp
index d5d6fd9..e47457b 100644
--- a/theta/include/theta_constants.hpp
+++ b/theta/include/theta_constants.hpp
@@ -21,14 +21,19 @@
 #define THETA_CONSTANTS_HPP_
 
 #include <climits>
+#include "common_defs.hpp"
 
 namespace datasketches {
 
 namespace theta_constants {
-  enum resize_factor { X1, X2, X4, X8 };
-  static const uint64_t MAX_THETA = LLONG_MAX; // signed max for compatibility with Java
-  static const uint8_t MIN_LG_K = 5;
-  static const uint8_t MAX_LG_K = 26;
+  using resize_factor = datasketches::resize_factor;
+  //enum resize_factor { X1, X2, X4, X8 };
+  const uint64_t MAX_THETA = LLONG_MAX; // signed max for compatibility with Java
+  const uint8_t MIN_LG_K = 5;
+  const uint8_t MAX_LG_K = 26;
+
+  const uint8_t DEFAULT_LG_K = 12;
+  const resize_factor DEFAULT_RESIZE_FACTOR = resize_factor::X8;
 }
 
 } /* namespace datasketches */
diff --git a/theta/include/theta_update_sketch_base.hpp b/theta/include/theta_update_sketch_base.hpp
index 4be1040..9d51c62 100644
--- a/theta/include/theta_update_sketch_base.hpp
+++ b/theta/include/theta_update_sketch_base.hpp
@@ -94,11 +94,14 @@
 template<typename Derived, typename Allocator>
 class theta_base_builder {
 public:
+  // TODO: Redundant and deprecated. Will be removed in next major verison release.
   using resize_factor = theta_constants::resize_factor;
   static const uint8_t MIN_LG_K = theta_constants::MIN_LG_K;
   static const uint8_t MAX_LG_K = theta_constants::MAX_LG_K;
-  static const uint8_t DEFAULT_LG_K = 12;
-  static const resize_factor DEFAULT_RESIZE_FACTOR = resize_factor::X8;
+  // TODO: The following defaults are redundant and deprecated. Will be removed in the
+  //       next major version release
+  static const uint8_t DEFAULT_LG_K = theta_constants::DEFAULT_LG_K;
+  static const resize_factor DEFAULT_RESIZE_FACTOR = theta_constants::DEFAULT_RESIZE_FACTOR;
 
   /**
    * Creates and instance of the builder with default parameters.
diff --git a/theta/include/theta_update_sketch_base_impl.hpp b/theta/include/theta_update_sketch_base_impl.hpp
index 947f085..b4a3124 100644
--- a/theta/include/theta_update_sketch_base_impl.hpp
+++ b/theta/include/theta_update_sketch_base_impl.hpp
@@ -271,7 +271,11 @@
 
 template<typename Derived, typename Allocator>
 theta_base_builder<Derived, Allocator>::theta_base_builder(const Allocator& allocator):
-allocator_(allocator), lg_k_(DEFAULT_LG_K), rf_(DEFAULT_RESIZE_FACTOR), p_(1), seed_(DEFAULT_SEED) {}
+allocator_(allocator),
+lg_k_(theta_constants::DEFAULT_LG_K),
+rf_(theta_constants::DEFAULT_RESIZE_FACTOR),
+p_(1),
+seed_(DEFAULT_SEED) {}
 
 template<typename Derived, typename Allocator>
 Derived& theta_base_builder<Derived, Allocator>::set_lg_k(uint8_t lg_k) {