diff --git a/poetry.lock b/poetry.lock
index 6cbb400..1a0c2f4 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -1,4 +1,4 @@
-# This file is automatically @generated by Poetry 1.7.1 and should not be changed by hand.
+# This file is automatically @generated by Poetry 1.8.5 and should not be changed by hand.
 
 [[package]]
 name = "alabaster"
@@ -528,7 +528,6 @@ files = [
     {file = "cryptography-44.0.0-cp37-abi3-manylinux_2_28_aarch64.whl", hash = "sha256:761817a3377ef15ac23cd7834715081791d4ec77f9297ee694ca1ee9c2c7e5eb"},
     {file = "cryptography-44.0.0-cp37-abi3-manylinux_2_28_x86_64.whl", hash = "sha256:3c672a53c0fb4725a29c303be906d3c1fa99c32f58abe008a82705f9ee96f40b"},
     {file = "cryptography-44.0.0-cp37-abi3-manylinux_2_34_aarch64.whl", hash = "sha256:4ac4c9f37eba52cb6fbeaf5b59c152ea976726b865bd4cf87883a7e7006cc543"},
-    {file = "cryptography-44.0.0-cp37-abi3-manylinux_2_34_x86_64.whl", hash = "sha256:60eb32934076fa07e4316b7b2742fa52cbb190b42c2df2863dbc4230a0a9b385"},
     {file = "cryptography-44.0.0-cp37-abi3-musllinux_1_2_aarch64.whl", hash = "sha256:ed3534eb1090483c96178fcb0f8893719d96d5274dfde98aa6add34614e97c8e"},
     {file = "cryptography-44.0.0-cp37-abi3-musllinux_1_2_x86_64.whl", hash = "sha256:f3f6fdfa89ee2d9d496e2c087cebef9d4fcbb0ad63c40e821b39f74bf48d9c5e"},
     {file = "cryptography-44.0.0-cp37-abi3-win32.whl", hash = "sha256:eb33480f1bad5b78233b0ad3e1b0be21e8ef1da745d8d2aecbb20671658b9053"},
@@ -539,7 +538,6 @@ files = [
     {file = "cryptography-44.0.0-cp39-abi3-manylinux_2_28_aarch64.whl", hash = "sha256:c5eb858beed7835e5ad1faba59e865109f3e52b3783b9ac21e7e47dc5554e289"},
     {file = "cryptography-44.0.0-cp39-abi3-manylinux_2_28_x86_64.whl", hash = "sha256:f53c2c87e0fb4b0c00fa9571082a057e37690a8f12233306161c8f4b819960b7"},
     {file = "cryptography-44.0.0-cp39-abi3-manylinux_2_34_aarch64.whl", hash = "sha256:9e6fc8a08e116fb7c7dd1f040074c9d7b51d74a8ea40d4df2fc7aa08b76b9e6c"},
-    {file = "cryptography-44.0.0-cp39-abi3-manylinux_2_34_x86_64.whl", hash = "sha256:9abcc2e083cbe8dde89124a47e5e53ec38751f0d7dfd36801008f316a127d7ba"},
     {file = "cryptography-44.0.0-cp39-abi3-musllinux_1_2_aarch64.whl", hash = "sha256:d2436114e46b36d00f8b72ff57e598978b37399d2786fd39793c36c6d5cb1c64"},
     {file = "cryptography-44.0.0-cp39-abi3-musllinux_1_2_x86_64.whl", hash = "sha256:a01956ddfa0a6790d594f5b34fc1bfa6098aca434696a03cfdbe469b8ed79285"},
     {file = "cryptography-44.0.0-cp39-abi3-win32.whl", hash = "sha256:eca27345e1214d1b9f9490d200f9db5a874479be914199194e746c893788d417"},
@@ -2743,12 +2741,12 @@ qiskit-ibm-runtime = ">=0.30.0"
 
 [[package]]
 name = "pytket-quantinuum"
-version = "0.41.0"
+version = "0.42.0"
 description = "Extension for pytket, providing access to Quantinuum backends"
 optional = true
 python-versions = ">=3.10"
 files = [
-    {file = "pytket_quantinuum-0.41.0-py3-none-any.whl", hash = "sha256:632fb515a7a5ce197a521a72d2a6553151b9c2cf42611af2b5c3ab3a245393ea"},
+    {file = "pytket_quantinuum-0.42.0-py3-none-any.whl", hash = "sha256:45f124475f212659cd7e9b5382a383240d12df5efb961afdd48760134f9a7884"},
 ]
 
 [package.dependencies]
@@ -2756,8 +2754,8 @@ msal = ">=1.18,<2.0"
 nest_asyncio = ">=1.2"
 numpy = ">=1.26.4"
 pyjwt = ">=2.4,<3.0"
-pytket = ">=1.35.0"
-pytket-pecos = {version = ">=0.1.31,<0.2.0", optional = true, markers = "extra == \"pecos\""}
+pytket = ">=1.37.0"
+pytket-pecos = {version = ">=0.1.32,<0.2.0", optional = true, markers = "extra == \"pecos\""}
 pytket-qir = ">=0.17,<0.18"
 requests = ">=2.32.2"
 types-requests = "*"
@@ -2765,7 +2763,7 @@ websockets = ">=13.1"
 
 [package.extras]
 calendar = ["matplotlib (>=3.8.3,<3.10.0)", "pandas (>=2.2.1,<2.3.0)"]
-pecos = ["pytket-pecos (>=0.1.31,<0.2.0)"]
+pecos = ["pytket-pecos (>=0.1.32,<0.2.0)"]
 
 [[package]]
 name = "pywin32"
@@ -4245,4 +4243,4 @@ tests = ["mypy", "pytest", "pytest-cov", "pytket-quantinuum", "qiskit-ibm-provid
 [metadata]
 lock-version = "2.0"
 python-versions = ">=3.10,<3.14"
-content-hash = "518fb4ebd0da46487bbb8279c79d26e244c3459d43ab11e8506fbd7ab91095f6"
+content-hash = "f9ef15b82527daf3f005adb7a5999aaabe4f3335fbbeb1aba294f701c1cced9b"
diff --git a/pyproject.toml b/pyproject.toml
index 3c05211..b8d2514 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -24,7 +24,7 @@ sphinx = { version = "^8.1.3", optional = true }
 pytest-cov = { version = "^6.0.0", optional = true }
 qiskit-ibm-provider = { version = "^0.11.0", optional = true }
 ruff = { version = "^0.8.1", optional = true }
-pytket-quantinuum = {extras = ["pecos"], version = "^0.41.0", optional = true}
+pytket-quantinuum = {extras = ["pecos"], version = ">=0.41,<0.43", optional = true}
 furo = { version = "^2024.8.6", optional = true }
 myst-nb = { version = "^1.1.2", optional = true}
 sphinx-autodoc-typehints = { version = "^2.5.0", optional = true }