diff --git a/extern/assert b/extern/assert
index 65068b2b..02256c84 160000
--- a/extern/assert
+++ b/extern/assert
@@ -1 +1 @@
-Subproject commit 65068b2b9adb23415f3b68de7a12f34e075c2101
+Subproject commit 02256c84fd0cd58a139d9dc1b25b5019ca976ada
diff --git a/extern/config b/extern/config
index e108255f..a1cf5d53 160000
--- a/extern/config
+++ b/extern/config
@@ -1 +1 @@
-Subproject commit e108255ffb5d2557ed3398b3fc575a2e9fd434cc
+Subproject commit a1cf5d531405e62927b0257b5cbecc66a545b508
diff --git a/extern/core b/extern/core
index a1ad1784..c7134904 160000
--- a/extern/core
+++ b/extern/core
@@ -1 +1 @@
-Subproject commit a1ad1784bfc21133f4d83fbf47dda961bb4a7c31
+Subproject commit c7134904e27237dbbb81ba28f0f23fc365b079dd
diff --git a/extern/histogram b/extern/histogram
index 8f3a3c07..a29729e6 160000
--- a/extern/histogram
+++ b/extern/histogram
@@ -1 +1 @@
-Subproject commit 8f3a3c07e47812460e1b6c68472fcdcf645fdcd6
+Subproject commit a29729e6682652800b06dc8aded29bbeb4acea61
diff --git a/extern/mp11 b/extern/mp11
index d15c63c0..ef7608b4 160000
--- a/extern/mp11
+++ b/extern/mp11
@@ -1 +1 @@
-Subproject commit d15c63c0a6426da25c41afa57f5260f806366289
+Subproject commit ef7608b463298b881bc82eae4f45a4385ed74fca
diff --git a/extern/pybind11 b/extern/pybind11
index 5b0a6fc2..aa304c9c 160000
--- a/extern/pybind11
+++ b/extern/pybind11
@@ -1 +1 @@
-Subproject commit 5b0a6fc2017fcc176545afe3e09c9f9885283242
+Subproject commit aa304c9c7d725ffb9d10af08a3b34cb372307020
diff --git a/extern/throw_exception b/extern/throw_exception
index 8c7b14f6..23dd41e9 160000
--- a/extern/throw_exception
+++ b/extern/throw_exception
@@ -1 +1 @@
-Subproject commit 8c7b14f68bebf8a82b4728d6a13f7601bc2b6073
+Subproject commit 23dd41e920ecd91237500ac6428f7d392a7a875c
diff --git a/extern/variant2 b/extern/variant2
index e4b4b3f0..e2546b70 160000
--- a/extern/variant2
+++ b/extern/variant2
@@ -1 +1 @@
-Subproject commit e4b4b3f02beb42c3dce3b5d352bc225ea6a6cb8f
+Subproject commit e2546b70ca04d4263f7a5917815506e488b6920f
diff --git a/include/bh_python/axis.hpp b/include/bh_python/axis.hpp
index 66acf728..f88d9e43 100644
--- a/include/bh_python/axis.hpp
+++ b/include/bh_python/axis.hpp
@@ -219,7 +219,10 @@ py::array_t<double> edges(const A& ax, bool flow = false, bool numpy_upper = fal
         for(index_type i = -underflow; i <= ax.size() + overflow; ++i)
             edges.mutable_at(i + underflow) = ax.value(i);
 
-        if(numpy_upper && !std::is_same<A, axis::regular_numpy>::value) {
+        if(numpy_upper
+           && !(std::is_same<A, axis::regular_none>::value
+                || std::is_same<A, axis::regular_uflow>::value
+                || std::is_same<A, axis::regular_numpy>::value)) {
             edges.mutable_at(ax.size() + underflow) = std::nextafter(
                 edges.at(ax.size() + underflow), std::numeric_limits<double>::min());
         }
diff --git a/src/boost_histogram/_core/axis/__init__.pyi b/src/boost_histogram/_core/axis/__init__.pyi
index dd9b2fc5..328046ed 100644
--- a/src/boost_histogram/_core/axis/__init__.pyi
+++ b/src/boost_histogram/_core/axis/__init__.pyi
@@ -57,7 +57,6 @@ class regular_oflow(_BaseRegular): ...
 class regular_uoflow(_BaseRegular): ...
 class regular_uoflow_growth(_BaseRegular): ...
 class regular_circular(_BaseRegular): ...
-class regular_numpy(_BaseRegular): ...
 
 class regular_pow(_BaseRegular):
     def __init__(self, bins: int, start: float, stop: float, power: float) -> None: ...
diff --git a/src/boost_histogram/_internal/axis.py b/src/boost_histogram/_internal/axis.py
index 4a007854..54e061ab 100644
--- a/src/boost_histogram/_internal/axis.py
+++ b/src/boost_histogram/_internal/axis.py
@@ -259,7 +259,6 @@ def widths(self) -> np.typing.NDArray[Any]:
         ca.regular_uflow,
         ca.regular_oflow,
         ca.regular_none,
-        ca.regular_numpy,
         ca.regular_pow,
         ca.regular_trans,
         ca.regular_circular,
diff --git a/src/boost_histogram/_internal/hist.py b/src/boost_histogram/_internal/hist.py
index 0708247e..9fa34ef0 100644
--- a/src/boost_histogram/_internal/hist.py
+++ b/src/boost_histogram/_internal/hist.py
@@ -791,9 +791,6 @@ def sum(self, flow: bool = False) -> float | Accumulator:
         """
         Compute the sum over the histogram bins (optionally including the flow bins).
         """
-        if any(x == 0 for x in (self.axes.extent if flow else self.axes.size)):
-            return self.storage_type.accumulator()
-
         return self._hist.sum(flow)  # type: ignore[no-any-return]
 
     @property
diff --git a/src/boost_histogram/numpy.py b/src/boost_histogram/numpy.py
index 1c755df8..74487447 100644
--- a/src/boost_histogram/numpy.py
+++ b/src/boost_histogram/numpy.py
@@ -13,12 +13,9 @@
 
 import numpy as np
 
-from boost_histogram import _core
-
 from . import axis as _axis
 from . import storage as _storage
 from ._internal import hist as _hist
-from ._internal.utils import cast as _cast
 
 __all__ = ("histogram", "histogram2d", "histogramdd")
 
@@ -69,7 +66,7 @@ def histogramdd(
     if range is None:
         range = (None,) * rank
 
-    axs = []
+    axs: list[_axis.Axis] = []
     for n, (b, r) in enumerate(zip(bins, range)):
         if np.issubdtype(type(b), np.integer):
             if r is None:
@@ -77,8 +74,9 @@ def histogramdd(
                 r = (np.amin(a[n]), np.amax(a[n]))  # noqa: PLW2901
                 if r[0] == r[1]:
                     r = (r[0] - 0.5, r[1] + 0.5)  # noqa: PLW2901
-            cpp_ax = _core.axis.regular_numpy(typing.cast(int, b), r[0], r[1])
-            new_ax = _cast(None, cpp_ax, _axis.Axis)
+            new_ax = _axis.Regular(
+                typing.cast(int, b), r[0], r[1], underflow=False, overflow=False
+            )
             axs.append(new_ax)
         else:
             barr: np.typing.NDArray[Any] = np.asarray(b, dtype=np.double)
diff --git a/tests/test_pickle.py b/tests/test_pickle.py
index 37deaec4..e4d9db57 100644
--- a/tests/test_pickle.py
+++ b/tests/test_pickle.py
@@ -80,10 +80,9 @@ def test_accumulators(accum, args, copy_fn):
     (bh.axis.StrCategory, (["1", "2", "3"],), {}),
     (bh.axis.StrCategory, (["1", "2", "3"],), {"growth": True}),
 ]
-raw_axes_creations = [(bh._core.axis.regular_numpy, (4, 2, 4), {})]
 
 
-@pytest.mark.parametrize(("axis", "args", "opts"), axes_creations + raw_axes_creations)
+@pytest.mark.parametrize(("axis", "args", "opts"), axes_creations)
 def test_axes(axis, args, opts, copy_fn):
     orig = axis(*args, **opts)
     new = copy_fn(orig)
@@ -188,16 +187,6 @@ def test_histogram_metadata(copy_fn, metadata):
     assert hist == new
 
 
-def test_numpy_edge(copy_fn):
-    ax1 = bh._core.axis.regular_numpy(10, 0, 1)
-    ax2 = copy_fn(ax1)
-
-    # stop defaults to 0, so this fails if the copy fails
-    assert ax1 == ax2
-    assert ax1.index(1) == ax2.index(1)
-    assert ax2.index(1) == 9
-
-
 @pytest.mark.skipif(
     platform.python_implementation() == "PyPy",
     reason="Not remotely supported on PyPY, hangs forever",