diff --git a/.github/workflows/test_and_build.yml b/.github/workflows/test_and_build.yml
index 2f48048de..5f1ab7dde 100644
--- a/.github/workflows/test_and_build.yml
+++ b/.github/workflows/test_and_build.yml
@@ -169,17 +169,17 @@ jobs:
           sparsever=$(python -c 'import random ; print(random.choice(["=0.13", "=0.14", ""]))')
           fmmver=$(python -c 'import random ; print(random.choice(["=1.4", "=1.5", "=1.6", "=1.7", ""]))')
           if [[ ${{ startsWith(steps.pyver.outputs.selected, '3.9') }} == true ]]; then
-            npver=$(python -c 'import random ; print(random.choice(["=1.21", "=1.22", "=1.23", "=1.24", "=1.25", ""]))')
+            npver=$(python -c 'import random ; print(random.choice(["=1.21", "=1.22", "=1.23", "=1.24", "=1.25", "=1.26", ""]))')
             spver=$(python -c 'import random ; print(random.choice(["=1.8", "=1.9", "=1.10", "=1.11", ""]))')
             pdver=$(python -c 'import random ; print(random.choice(["=1.2", "=1.3", "=1.4", "=1.5", "=2.0", "=2.1", ""]))')
             akver=$(python -c 'import random ; print(random.choice(["=1.9", "=1.10", "=2.0", "=2.1", "=2.2", "=2.3", "=2.4", ""]))')
           elif [[ ${{ startsWith(steps.pyver.outputs.selected, '3.10') }} == true ]]; then
-            npver=$(python -c 'import random ; print(random.choice(["=1.21", "=1.22", "=1.23", "=1.24", "=1.25", ""]))')
+            npver=$(python -c 'import random ; print(random.choice(["=1.21", "=1.22", "=1.23", "=1.24", "=1.25", "=1.26", ""]))')
             spver=$(python -c 'import random ; print(random.choice(["=1.8", "=1.9", "=1.10", "=1.11", ""]))')
             pdver=$(python -c 'import random ; print(random.choice(["=1.3", "=1.4", "=1.5", "=2.0", "=2.1", ""]))')
             akver=$(python -c 'import random ; print(random.choice(["=1.9", "=1.10", "=2.0", "=2.1", "=2.2", "=2.3", "=2.4", ""]))')
           else  # Python 3.11
-            npver=$(python -c 'import random ; print(random.choice(["=1.23", "=1.24", "=1.25", ""]))')
+            npver=$(python -c 'import random ; print(random.choice(["=1.23", "=1.24", "=1.25", "=1.26", ""]))')
             spver=$(python -c 'import random ; print(random.choice(["=1.9", "=1.10", "=1.11", ""]))')
             pdver=$(python -c 'import random ; print(random.choice(["=1.5", "=2.0", "=2.1", ""]))')
             akver=$(python -c 'import random ; print(random.choice(["=1.10", "=2.0", "=2.1", "=2.2", "=2.3", "=2.4", ""]))')
@@ -206,7 +206,7 @@ jobs:
           else
             psgver=""
           fi
-          if [[ ${npver} == "=1.25" ]] ; then
+          if [[ ${npver} == "=1.25" || ${npver} == "=1.26" ]] ; then
             numbaver=""
             if [[ ${spver} == "=1.8" ]] ; then
               spver=$(python -c 'import random ; print(random.choice(["=1.9", "=1.10", "=1.11", ""]))')
@@ -243,7 +243,8 @@ jobs:
               pdver=""
               yamlver=""
             fi
-          elif [[ ${npver} == "=1.25" ]] ; then
+          elif [[ ${npver} == "=1.25" || ${npver} == "=1.26" ]] ; then
+            # Don't install numba for unsupported versions of numpy
             numba=""
             numbaver=NA
             sparse=""
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 5a499e8f8..a945fe49a 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -51,7 +51,7 @@ repos:
       - id: isort
   # Let's keep `pyupgrade` even though `ruff --fix` probably does most of it
   - repo: https://github.com/asottile/pyupgrade
-    rev: v3.10.1
+    rev: v3.12.0
     hooks:
       - id: pyupgrade
         args: [--py39-plus]
@@ -61,12 +61,12 @@ repos:
       - id: auto-walrus
         args: [--line-length, "100"]
   - repo: https://github.com/psf/black
-    rev: 23.7.0
+    rev: 23.9.1
     hooks:
       - id: black
       - id: black-jupyter
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.0.287
+    rev: v0.0.290
     hooks:
       - id: ruff
         args: [--fix-only, --show-fixes]
@@ -79,7 +79,7 @@ repos:
         additional_dependencies: &flake8_dependencies
         # These versions need updated manually
         - flake8==6.1.0
-        - flake8-bugbear==23.7.10
+        - flake8-bugbear==23.9.16
         - flake8-simplify==0.20.0
   - repo: https://github.com/asottile/yesqa
     rev: v1.5.0
@@ -94,7 +94,7 @@ repos:
         additional_dependencies: [tomli]
         files: ^(graphblas|docs)/
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.0.287
+    rev: v0.0.290
     hooks:
       - id: ruff
   - repo: https://github.com/sphinx-contrib/sphinx-lint
diff --git a/graphblas/core/matrix.py b/graphblas/core/matrix.py
index d820ca424..aed98f57d 100644
--- a/graphblas/core/matrix.py
+++ b/graphblas/core/matrix.py
@@ -2805,6 +2805,119 @@ def power(self, n, op=semiring.plus_times):
             dtype=self.dtype,
         )
 
+    def setdiag(self, values, k=0, *, mask=None, accum=None, **opts):
+        """Set k'th diagonal with a Scalar, Vector, or array.
+
+        This is not a built-in GraphBLAS operation. It is implemented as a recipe.
+
+        Parameters
+        ----------
+        values : Vector or list or np.ndarray or scalar
+            New values to assign to the diagonal. The length of Vector and array
+            values must match the size of the diagonal being assigned to.
+        k : int, default=0
+            Which diagonal or off-diagonal to set. For example, set the elements
+            ``A[i, i+k] = values[i]``. The default, k=0, is the main diagonal.
+        mask : Mask, optional
+            Vector or Matrix Mask to control which diagonal elements to set.
+            If it is Matrix Mask, then only the diagonal is used as the mask.
+        accum : Monoid or BinaryOp, optional
+            Operator to use to combine existing diagonal values and new values.
+        """
+        if (K := maybe_integral(k)) is None:
+            raise TypeError(f"k must be an integer; got bad type: {type(k)}")
+        k = K
+        if k < 0:
+            if (size := min(self._nrows + k, self._ncols)) <= 0 and k <= -self._nrows:
+                raise IndexError(
+                    f"k={k} is too small; the k'th diagonal is out of range. "
+                    f"Valid k for Matrix with shape {self._nrows}x{self._ncols}: "
+                    f"{-self._nrows} {'<' if self._nrows else '<='} k "
+                    f"{'<' if self._ncols else '<='} {self._ncols}"
+                )
+        elif (size := min(self._ncols - k, self._nrows)) <= 0 and k > 0 and k >= self._ncols:
+            raise IndexError(
+                f"k={k} is too large; the k'th diagonal is out of range. "
+                f"Valid k for Matrix with shape {self._nrows}x{self._ncols}: "
+                f"{-self._nrows} {'<' if self._nrows else '<='} k "
+                f"{'<' if self._ncols else '<='} {self._ncols}"
+            )
+
+        # Convert `values` to Vector if necessary (i.e., it's scalar or array)
+        is_scalar = clear_diag = False
+        if output_type(values) is Vector:
+            v = values
+            clear_diag = accum is None and v._nvals != v._size
+        elif type(values) is Scalar:
+            is_scalar = True
+        else:
+            dtype = self.dtype if self.dtype._is_udt else None
+            try:
+                # Try to make it a Scalar
+                values = Scalar.from_value(values, dtype, is_cscalar=None, name="")
+                is_scalar = True
+            except (TypeError, ValueError):
+                try:
+                    # Else try to make it a numpy array
+                    values, dtype = values_to_numpy_buffer(values, dtype)
+                except Exception:
+                    self._expect_type(
+                        values,
+                        (Scalar, Vector, np.ndarray),
+                        within="setdiag",
+                        argname="values",
+                        extra_message="Literal scalars also accepted.",
+                    )
+                else:
+                    v = Vector.from_dense(values, dtype=dtype, **opts)
+
+        if is_scalar:
+            v = Vector.from_scalar(values, size, **opts)
+        elif v._size != size:
+            raise DimensionMismatch(
+                f"Dimensions not compatible for assigning length {v._size} Vector "
+                f"to {k}'th diagonal of Matrix with shape {self._nrows}x{self._ncols}."
+                f"The Vector should be size {size}."
+            )
+
+        if mask is not None:
+            mask = _check_mask(mask)
+            if mask.parent.ndim == 2:
+                if mask.parent.shape != self.shape:
+                    raise DimensionMismatch(
+                        "Matrix mask in setdiag is the wrong shape; "
+                        f"expected shape {self._nrows}x{self._ncols}, "
+                        f"got {mask.parent._nrows}x{mask.parent._ncols}"
+                    )
+                if mask.complement:
+                    mval = type(mask)(mask.parent.diag(k)).new(**opts)
+                    mask = mval.S
+                    M = mval.diag()
+                else:
+                    M = select.diag(mask.parent, k).new(**opts)
+            elif mask.parent._size != size:
+                raise DimensionMismatch(
+                    "Vector mask in setdiag is the wrong length; "
+                    f"expected size {size}, got size {mask.parent._size}."
+                )
+            else:
+                if mask.complement:
+                    mask = mask.new(**opts).S
+                M = mask.parent.diag()
+            if M.shape != self.shape:
+                M.resize(self._nrows, self._ncols)
+            mask = type(mask)(M)
+
+        if clear_diag:
+            self(mask=mask, **opts) << select.offdiag(self, k)
+
+        Diag = v.diag(k)
+        if Diag.shape != self.shape:
+            Diag.resize(self._nrows, self._ncols)
+        if mask is None:
+            mask = Diag.S
+        self(accum=accum, mask=mask, **opts) << Diag
+
     ##################################
     # Extract and Assign index methods
     ##################################
diff --git a/graphblas/tests/test_matrix.py b/graphblas/tests/test_matrix.py
index fe85bb9bf..e08f96b32 100644
--- a/graphblas/tests/test_matrix.py
+++ b/graphblas/tests/test_matrix.py
@@ -2940,6 +2940,7 @@ def test_expr_is_like_matrix(A):
         "from_scalar",
         "from_values",
         "resize",
+        "setdiag",
         "update",
     }
     ignore = {"__sizeof__"}
@@ -3002,9 +3003,10 @@ def test_index_expr_is_like_matrix(A):
         "from_dense",
         "from_dicts",
         "from_edgelist",
-        "from_values",
         "from_scalar",
+        "from_values",
         "resize",
+        "setdiag",
     }
     ignore = {"__sizeof__"}
     assert attrs - expr_attrs - ignore == expected, (
@@ -4393,3 +4395,135 @@ def test_power(A):
     B = A[:2, :3].new()
     with pytest.raises(DimensionMismatch):
         B.power(2)
+
+
+def test_setdiag():
+    A = Matrix(int, 2, 3)
+    A.setdiag(1)
+    expected = Matrix(int, 2, 3)
+    expected[0, 0] = 1
+    expected[1, 1] = 1
+    assert A.isequal(expected)
+    A.setdiag(Scalar.from_value(2), 2)
+    expected[0, 2] = 2
+    assert A.isequal(expected)
+    A.setdiag(3, k=-1)
+    expected[1, 0] = 3
+    assert A.isequal(expected)
+    # List (or array) is treated as dense
+    A.setdiag([10, 20], 1)
+    expected[0, 1] = 10
+    expected[1, 2] = 20
+    assert A.isequal(expected)
+    # Size 0 diagonals, which does not set anything.
+    # This could be valid (esp. given a size 0 vector), but let's raise for now.
+    with pytest.raises(IndexError, match="diagonal is out of range"):
+        A.setdiag(-1, 3)
+    with pytest.raises(IndexError, match="diagonal is out of range"):
+        A.setdiag(-1, -2)
+    with pytest.raises(IndexError, match="diagonal is out of range"):
+        A.setdiag([], 3)
+    with pytest.raises(IndexError, match="diagonal is out of range"):
+        A.setdiag(Vector(int, 0), -2)
+    # Now we're definitely out of bounds
+    with pytest.raises(IndexError, match="diagonal is out of range"):
+        A.setdiag(-1, 4)
+    with pytest.raises(IndexError, match="diagonal is out of range"):
+        A.setdiag(-1, -3)
+    with pytest.raises(TypeError, match="k must be an integer"):
+        A.setdiag(-1, 0.5)
+    with pytest.raises(TypeError, match="Bad type for argument `values` in Matrix.setdiag"):
+        A.setdiag(object())
+    with pytest.raises(DimensionMismatch, match="Dimensions not compatible"):
+        A.setdiag([10, 20, 30], 1)
+    with pytest.raises(DimensionMismatch, match="Dimensions not compatible"):
+        A.setdiag([10], 1)
+
+    # Special care for dimensions of length 0
+    A = Matrix(int, 0, 2, name="A")
+    A.setdiag(0, 0)
+    A.setdiag(0, 1)
+    A.setdiag([], 0)
+    A.setdiag([], 1)
+    with pytest.raises(IndexError, match="diagonal is out of range"):
+        A.setdiag(0, -1)
+    with pytest.raises(IndexError, match="diagonal is out of range"):
+        A.setdiag([], -1)
+    A = Matrix(int, 2, 0, name="A")
+    A.setdiag(0, 0)
+    A.setdiag(0, -1)
+    A.setdiag([], 0)
+    A.setdiag([], -1)
+    with pytest.raises(IndexError, match="diagonal is out of range"):
+        A.setdiag(0, 1)
+    with pytest.raises(IndexError, match="diagonal is out of range"):
+        A.setdiag([], 1)
+    A = Matrix(int, 0, 0, name="A")
+    A.setdiag(0, 0)
+    A.setdiag([], 0)
+    with pytest.raises(IndexError, match="diagonal is out of range"):
+        A.setdiag(0, 1)
+    with pytest.raises(IndexError, match="diagonal is out of range"):
+        A.setdiag([], 1)
+    with pytest.raises(IndexError, match="diagonal is out of range"):
+        A.setdiag(0, -1)
+    with pytest.raises(IndexError, match="diagonal is out of range"):
+        A.setdiag([], -1)
+
+    A = Matrix(int, 2, 2, name="A")
+    expected = Matrix(int, 2, 2, name="expected")
+    v = Vector(int, 2, name="v")
+    Vector(int, 2)
+    v[0] = 1
+    A.setdiag(v)
+    expected[0, 0] = 1
+    assert A.isequal(expected)
+    A.setdiag(v, accum=binary.plus)
+    expected[0, 0] = 2
+    assert A.isequal(expected)
+    A.setdiag(10, mask=v.S)
+    expected[0, 0] = 10
+    assert A.isequal(expected)
+    A.setdiag(10, mask=v.S, accum="+")
+    expected[0, 0] = 20
+    assert A.isequal(expected)
+    # Allow mask to be a matrix
+    A.setdiag(10, mask=A.S, accum="+")
+    expected[0, 0] = 30
+    assert A.isequal(expected)
+    # Test how to clear or not clear missing elements
+    A.clear()
+    A.setdiag(99)
+    A.setdiag(v)
+    expected[0, 0] = 1
+    assert A.isequal(expected)
+    A.setdiag(99)
+    A.setdiag(v, accum="second")
+    expected[1, 1] = 99
+    assert A.isequal(expected)
+    A.setdiag(99)
+    A.setdiag(v, mask=v.S)
+    assert A.isequal(expected)
+
+    # We handle complemented masks!
+    A.clear()
+    expected.clear()
+    A.setdiag(42, mask=~v.S)
+    expected[1, 1] = 42
+    assert A.isequal(expected)
+    A.setdiag(7, mask=~A.V)
+    expected[0, 0] = 7
+    assert A.isequal(expected)
+
+    with pytest.raises(DimensionMismatch, match="Matrix mask in setdiag is the wrong "):
+        A.setdiag(9, mask=Matrix(int, 3, 3).S)
+    with pytest.raises(DimensionMismatch, match="Vector mask in setdiag is the wrong "):
+        A.setdiag(10, mask=Vector(int, 3).S)
+
+    A.clear()
+    A.resize(2, 3)
+    expected.clear()
+    expected.resize(2, 3)
+    A.setdiag(30, mask=v.S)
+    expected[0, 0] = 30
+    assert A.isequal(expected)
diff --git a/graphblas/tests/test_ssjit.py b/graphblas/tests/test_ssjit.py
index 57cb2bbba..bd05cf2db 100644
--- a/graphblas/tests/test_ssjit.py
+++ b/graphblas/tests/test_ssjit.py
@@ -1,4 +1,5 @@
 import os
+import pathlib
 import sys
 
 import numpy as np
@@ -82,6 +83,10 @@ def _setup_jit():
         gb.ss.config["jit_c_libraries"] = ""
         gb.ss.config["jit_c_cmake_libs"] = ""
 
+    if not pathlib.Path(gb.ss.config["jit_c_compiler_name"]).exists():
+        # Can't use the JIT if we don't have a compiler!
+        gb.ss.config["jit_c_control"] = "off"
+
 
 @pytest.fixture
 def v():
diff --git a/pyproject.toml b/pyproject.toml
index 619ce18f2..ff970cc0f 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -235,6 +235,9 @@ ignore-words-list = "coo,ba"
 # https://github.com/charliermarsh/ruff/
 line-length = 100
 target-version = "py39"
+unfixable = [
+    "F841"  # unused-variable (Note: can leave useless expression)
+]
 select = [
     # Have we enabled too many checks that they'll become a nuisance? We'll see...
     "F",  # pyflakes
diff --git a/scripts/check_versions.sh b/scripts/check_versions.sh
index 1a3e894a6..a76fee1d2 100755
--- a/scripts/check_versions.sh
+++ b/scripts/check_versions.sh
@@ -3,15 +3,15 @@
 # Use, adjust, copy/paste, etc. as necessary to answer your questions.
 # This may be helpful when updating dependency versions in CI.
 # Tip: add `--json` for more information.
-conda search 'numpy[channel=conda-forge]>=1.25.2'
-conda search 'pandas[channel=conda-forge]>=2.1.0'
+conda search 'flake8-bugbear[channel=conda-forge]>=23.9.16'
+conda search 'flake8-simplify[channel=conda-forge]>=0.20.0'
+conda search 'numpy[channel=conda-forge]>=1.26.0'
+conda search 'pandas[channel=conda-forge]>=2.1.1'
 conda search 'scipy[channel=conda-forge]>=1.11.2'
 conda search 'networkx[channel=conda-forge]>=3.1'
-conda search 'awkward[channel=conda-forge]>=2.4.1'
+conda search 'awkward[channel=conda-forge]>=2.4.3'
 conda search 'sparse[channel=conda-forge]>=0.14.0'
-conda search 'fast_matrix_market[channel=conda-forge]>=1.7.2'
+conda search 'fast_matrix_market[channel=conda-forge]>=1.7.3'
 conda search 'numba[channel=conda-forge]>=0.57.1'
 conda search 'pyyaml[channel=conda-forge]>=6.0.1'
-conda search 'flake8-bugbear[channel=conda-forge]>=23.7.10'
-conda search 'flake8-simplify[channel=conda-forge]>=0.20.0'
 # conda search 'python[channel=conda-forge]>=3.9 *pypy*'