diff --git a/dev_tools/requirements/deps/runtime.txt b/dev_tools/requirements/deps/runtime.txt
index 53d1a689e..88e5892f3 100644
--- a/dev_tools/requirements/deps/runtime.txt
+++ b/dev_tools/requirements/deps/runtime.txt
@@ -2,9 +2,9 @@
 attrs>=23.2.0
 cachetools>=5.3
 networkx
-numpy
+numpy~=1.26
 sympy
-cirq-core==1.4
+cirq-core>=1.4.0,<1.6
 fxpmath
 galois
 
diff --git a/dev_tools/requirements/envs/dev.env.txt b/dev_tools/requirements/envs/dev.env.txt
index 832df2303..9f759d4fd 100644
--- a/dev_tools/requirements/envs/dev.env.txt
+++ b/dev_tools/requirements/envs/dev.env.txt
@@ -94,7 +94,7 @@ cffi==1.17.1
     #   cryptography
 charset-normalizer==3.4.3
     # via requests
-cirq-core==1.4.0
+cirq-core==1.5.0
     # via
     #   -r deps/runtime.txt
     #   openfermion
diff --git a/dev_tools/requirements/envs/docs.env.txt b/dev_tools/requirements/envs/docs.env.txt
index 9c54fae7d..fc883eaed 100644
--- a/dev_tools/requirements/envs/docs.env.txt
+++ b/dev_tools/requirements/envs/docs.env.txt
@@ -123,7 +123,7 @@ charset-normalizer==3.4.3
     # via
     #   -c envs/dev.env.txt
     #   requests
-cirq-core==1.4.0
+cirq-core==1.5.0
     # via
     #   -c envs/dev.env.txt
     #   -r deps/runtime.txt
diff --git a/dev_tools/requirements/envs/format.env.txt b/dev_tools/requirements/envs/format.env.txt
index 7a1f265ca..36b1898b5 100644
--- a/dev_tools/requirements/envs/format.env.txt
+++ b/dev_tools/requirements/envs/format.env.txt
@@ -109,7 +109,7 @@ charset-normalizer==3.4.3
     # via
     #   -c envs/dev.env.txt
     #   requests
-cirq-core==1.4.0
+cirq-core==1.5.0
     # via
     #   -c envs/dev.env.txt
     #   -r deps/runtime.txt
diff --git a/dev_tools/requirements/envs/mypy.env.txt b/dev_tools/requirements/envs/mypy.env.txt
index a73204217..fc563b1f3 100644
--- a/dev_tools/requirements/envs/mypy.env.txt
+++ b/dev_tools/requirements/envs/mypy.env.txt
@@ -101,7 +101,7 @@ charset-normalizer==3.4.3
     # via
     #   -c envs/dev.env.txt
     #   requests
-cirq-core==1.4.0
+cirq-core==1.5.0
     # via
     #   -c envs/dev.env.txt
     #   -r deps/runtime.txt
diff --git a/dev_tools/requirements/envs/pylint.env.txt b/dev_tools/requirements/envs/pylint.env.txt
index 47c171c0b..f60f73ec0 100644
--- a/dev_tools/requirements/envs/pylint.env.txt
+++ b/dev_tools/requirements/envs/pylint.env.txt
@@ -122,7 +122,7 @@ charset-normalizer==3.4.3
     # via
     #   -c envs/dev.env.txt
     #   requests
-cirq-core==1.4.0
+cirq-core==1.5.0
     # via
     #   -c envs/dev.env.txt
     #   -r deps/runtime.txt
diff --git a/dev_tools/requirements/envs/pytest.env.txt b/dev_tools/requirements/envs/pytest.env.txt
index 0f27f63cc..9b379ccbf 100644
--- a/dev_tools/requirements/envs/pytest.env.txt
+++ b/dev_tools/requirements/envs/pytest.env.txt
@@ -109,7 +109,7 @@ charset-normalizer==3.4.3
     # via
     #   -c envs/dev.env.txt
     #   requests
-cirq-core==1.4.0
+cirq-core==1.5.0
     # via
     #   -c envs/dev.env.txt
     #   -r deps/runtime.txt
diff --git a/dev_tools/requirements/envs/runtime.env.txt b/dev_tools/requirements/envs/runtime.env.txt
index e9154812e..45b4197af 100644
--- a/dev_tools/requirements/envs/runtime.env.txt
+++ b/dev_tools/requirements/envs/runtime.env.txt
@@ -101,7 +101,7 @@ charset-normalizer==3.4.3
     # via
     #   -c envs/dev.env.txt
     #   requests
-cirq-core==1.4.0
+cirq-core==1.5.0
     # via
     #   -c envs/dev.env.txt
     #   -r deps/runtime.txt
diff --git a/qualtran/bloqs/bookkeeping/split_test.py b/qualtran/bloqs/bookkeeping/split_test.py
index 685d7664a..4ad2d5012 100644
--- a/qualtran/bloqs/bookkeeping/split_test.py
+++ b/qualtran/bloqs/bookkeeping/split_test.py
@@ -70,10 +70,15 @@ def test_classical_sim_dtypes():
     assert isinstance(xx, np.ndarray)
     assert xx.tolist() == [1, 1, 1, 1, 1, 1, 1, 1]
 
-    # Warning: numpy will wrap too-large values
-    (xx,) = s.call_classically(reg=np.uint8(256))
-    assert isinstance(xx, np.ndarray)
-    assert xx.tolist() == [0, 0, 0, 0, 0, 0, 0, 0]
+    numpy_major_version = int(np.__version__.split('.')[0])
+    if numpy_major_version < 2:
+        # Warning: numpy 1 will wrap too-large values
+        (xx,) = s.call_classically(reg=np.uint8(256))
+        assert isinstance(xx, np.ndarray)
+        assert xx.tolist() == [0, 0, 0, 0, 0, 0, 0, 0]
+    else:
+        with pytest.raises(OverflowError):
+            (xx,) = s.call_classically(reg=np.uint8(256))
 
     with pytest.raises(ValueError):
         _ = s.call_classically(reg=np.uint16(256))
diff --git a/qualtran/bloqs/swap_network/cswap_approx.py b/qualtran/bloqs/swap_network/cswap_approx.py
index 362798e24..eb2eea04b 100644
--- a/qualtran/bloqs/swap_network/cswap_approx.py
+++ b/qualtran/bloqs/swap_network/cswap_approx.py
@@ -72,6 +72,7 @@ def decompose_from_registers(
     ) -> Iterator[cirq.OP_TREE]:
         ctrl, target_x, target_y = quregs['ctrl'], quregs['x'], quregs['y']
 
+
         def g(q: cirq.Qid, adjoint=False) -> Iterator[cirq.OP_TREE]:
             yield [cirq.S(q), cirq.H(q)]
             yield cirq.T(q) ** (1 - 2 * adjoint)