diff --git a/pyproject.toml b/pyproject.toml
index f06781c..5f84283 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -14,6 +14,7 @@ classifiers = [
   "Operating System :: OS Independent"
 ]
 dependencies = [
+  "circulax>=0.2.3",
   "gdsfactory~=9.45.0",
   "gplugins[sax,femwell,tidy3d]~=2.1.0",
   "doroutes~=1.1.0"
diff --git a/uv.lock b/uv.lock
index dbe2467..fc05bed 100644
--- a/uv.lock
+++ b/uv.lock
@@ -504,6 +504,28 @@ wheels = [
     { url = "https://files.pythonhosted.org/packages/db/8f/61959034484a4a7c527811f4721e75d02d653a35afb0b6054474d8185d4c/charset_normalizer-3.4.7-py3-none-any.whl", hash = "sha256:3dce51d0f5e7951f8bb4900c257dad282f49190fdbebecd4ba99bcc41fef404d", size = 61958, upload-time = "2026-04-02T09:28:37.794Z" },
 ]
 
+[[package]]
+name = "circulax"
+version = "0.2.3"
+source = { registry = "https://pypi.org/simple" }
+dependencies = [
+    { name = "diffrax" },
+    { name = "equinox" },
+    { name = "jax" },
+    { name = "jaxlib" },
+    { name = "kfnetlist" },
+    { name = "klujax" },
+    { name = "lineax" },
+    { name = "matplotlib" },
+    { name = "numpy" },
+    { name = "sax" },
+    { name = "typing-extensions" },
+]
+sdist = { url = "https://files.pythonhosted.org/packages/ae/d7/d4838228e30a54ab4dbc78682364a7fbeb8e9031db3180ef7cc10e269943/circulax-0.2.3.tar.gz", hash = "sha256:3ea8f6f5a0b175a034de3bdae64dc77ea121b9a758524d5c50ccfaaed22aecaa", size = 3492258, upload-time = "2026-07-31T08:16:00.09Z" }
+wheels = [
+    { url = "https://files.pythonhosted.org/packages/1d/bf/0ad8b46152e90699af38df5c063fc999269c56c4290d626579f91a41a563/circulax-0.2.3-py3-none-any.whl", hash = "sha256:d5a99d207ce6053acb5adfc17fd35ed057ff13d6a1264de0523d9c995c4c9c15", size = 190958, upload-time = "2026-07-31T08:15:57.505Z" },
+]
+
 [[package]]
 name = "cli-ui"
 version = "0.19.0"
@@ -743,6 +765,7 @@ name = "cspdk"
 version = "1.4.4"
 source = { editable = "." }
 dependencies = [
+    { name = "circulax" },
     { name = "doroutes" },
     { name = "gdsfactory" },
     { name = "gplugins", extra = ["femwell", "sax", "tidy3d"] },
@@ -771,8 +794,9 @@ docs = [
 
 [package.metadata]
 requires-dist = [
+    { name = "circulax", specifier = ">=0.2.3" },
     { name = "doroutes", specifier = "~=1.1.0" },
-    { name = "gdsfactory", specifier = "~=9.44.0" },
+    { name = "gdsfactory", specifier = "~=9.45.0" },
     { name = "gdsfactoryplus", marker = "extra == 'dev'" },
     { name = "gplugins", extras = ["sax", "femwell", "tidy3d"], specifier = "~=2.1.0" },
     { name = "jsondiff", marker = "extra == 'dev'" },
@@ -892,6 +916,24 @@ wheels = [
     { url = "https://files.pythonhosted.org/packages/07/6c/aa3f2f849e01cb6a001cd8554a88d4c77c5c1a31c95bdf1cf9301e6d9ef4/defusedxml-0.7.1-py2.py3-none-any.whl", hash = "sha256:a352e7e428770286cc899e2542b6cdaedb2b4953ff269a210103ec58f6198a61", size = 25604, upload-time = "2021-03-08T10:59:24.45Z" },
 ]
 
+[[package]]
+name = "diffrax"
+version = "0.7.2"
+source = { registry = "https://pypi.org/simple" }
+dependencies = [
+    { name = "equinox" },
+    { name = "jax" },
+    { name = "jaxtyping" },
+    { name = "lineax" },
+    { name = "optimistix" },
+    { name = "typing-extensions" },
+    { name = "wadler-lindig" },
+]
+sdist = { url = "https://files.pythonhosted.org/packages/5a/ea/a22853377a840d70d1d174d43183f12990c66eecf34ba7e76eec781249d0/diffrax-0.7.2.tar.gz", hash = "sha256:9adc70fe90dba83f7dd839845839b2531a3dd736a3944fe1aa26598507cfb48e", size = 155159, upload-time = "2026-02-18T01:14:04.964Z" }
+wheels = [
+    { url = "https://files.pythonhosted.org/packages/6c/48/c42f657f3d6b4d9d9674c9bc48e763d024511ea4cc1d6e0c68c7b4380c43/diffrax-0.7.2-py3-none-any.whl", hash = "sha256:1beee2f991cd049962fe3c89da28f933753aa66d80bef857533276c9f23301ed", size = 199673, upload-time = "2026-02-18T01:14:03.38Z" },
+]
+
 [[package]]
 name = "distlib"
 version = "0.4.0"
@@ -977,6 +1019,21 @@ wheels = [
     { url = "https://files.pythonhosted.org/packages/93/3d/8b393b35016909143ecac7bf7bf418f79236e1f83faf3867b5c5cb50c97f/embreex-4.4.0-cp314-cp314t-win_amd64.whl", hash = "sha256:a2fedc756a36729da6803425398aa4987b27d1d89e9fad403d8ef371fad5ca01", size = 13389585, upload-time = "2026-04-22T19:47:31.398Z" },
 ]
 
+[[package]]
+name = "equinox"
+version = "0.13.8"
+source = { registry = "https://pypi.org/simple" }
+dependencies = [
+    { name = "jax" },
+    { name = "jaxtyping" },
+    { name = "typing-extensions" },
+    { name = "wadler-lindig" },
+]
+sdist = { url = "https://files.pythonhosted.org/packages/19/ff/522336d2f8264f2ad97119710b76e2cddf66145d03a1e89899175d26b192/equinox-0.13.8.tar.gz", hash = "sha256:dd075050018e2dd02e252e9d29d3060f7e67f085622d8d27a8e89e24bb8523db", size = 145257, upload-time = "2026-05-05T10:03:43.258Z" }
+wheels = [
+    { url = "https://files.pythonhosted.org/packages/ae/d6/69a76c8ccdef14af687c497040292a46e59fc7a0ab24724b60e50ca61030/equinox-0.13.8-py3-none-any.whl", hash = "sha256:ca004348533cc30a63ebe8823d7dd4bb626dce17743d40bbddb89b402ef2a240", size = 185813, upload-time = "2026-05-05T10:03:41.673Z" },
+]
+
 [[package]]
 name = "executing"
 version = "2.2.1"
@@ -1151,7 +1208,7 @@ wheels = [
 
 [[package]]
 name = "gdsfactory"
-version = "9.44.0"
+version = "9.45.0"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "attrs" },
@@ -1187,9 +1244,9 @@ dependencies = [
     { name = "typing-extensions" },
     { name = "watchdog" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/2c/77/6b1751eab32f1ec7c4506a2dadb59194878f729de84905756b1c3a438343/gdsfactory-9.44.0.tar.gz", hash = "sha256:f993d35df133110938a368a6a3de60c23672ec7e5877a37c17eb92c630077727", size = 555361, upload-time = "2026-06-12T15:33:26.068Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/1b/2c/46796cd9e022fc2f5a54b82bcfd7c5a45f5edfe6889461e5320d9ce2837e/gdsfactory-9.45.0.tar.gz", hash = "sha256:618781460dbaa4e50a2039b14a3ba88ef53f6b46bd90c98f12f3aa4f5bd45896", size = 558352, upload-time = "2026-07-03T13:32:15.991Z" }
 wheels = [
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+    { url = "https://files.pythonhosted.org/packages/d4/a6/c7a7cb059f57df14f13dbad7dcd069a5eafdcfa970288d4b4cafb6c6871e/gdsfactory-9.45.0-py3-none-any.whl", hash = "sha256:98a3c13b23b8740083e71c3ea8fbf75fe6f729416943efa5eb76b18ebd7d5100", size = 809978, upload-time = "2026-07-03T13:32:14.245Z" },
 ]
 
 [[package]]
@@ -2011,7 +2068,7 @@ wheels = [
 
 [[package]]
 name = "kfactory"
-version = "2.5.3"
+version = "2.6.1"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "aenum" },
@@ -2032,9 +2089,9 @@ dependencies = [
     { name = "toolz" },
     { name = "typer" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/1b/41/4f6df622887085e10f1753283696f295c6b5e45aa4a3c2a9dae599c81ff8/kfactory-2.5.3.tar.gz", hash = "sha256:1e8fbe04191109e018506f48fde47bdaa4a9a1247864708b33c11ca49c51064b", size = 13526132, upload-time = "2026-05-21T11:39:04.866Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/de/b1/db2bbdffe2c28032661fe306eb2dae1b54c0f85592d4b86b326453044653/kfactory-2.6.1.tar.gz", hash = "sha256:e469e52efa3d853df89b4ec15d0324b2a389555e0ec8fce5bd347d32e2c0ca97", size = 13551991, upload-time = "2026-07-01T22:44:46.038Z" }
 wheels = [
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+    { url = "https://files.pythonhosted.org/packages/e4/29/dae62742e7b675c01b1d6e2dd8ee88cdb59a5d1ccf482818bda1d471333f/kfactory-2.6.1-py3-none-any.whl", hash = "sha256:34324989d4a5fa99aee636b7378ad42404d685cb754b40ad9f90280c321a02ea", size = 255125, upload-time = "2026-07-01T22:44:43.472Z" },
 ]
 
 [package.optional-dependencies]
@@ -2045,6 +2102,19 @@ ipy = [
     { name = "ipywidgets" },
 ]
 
+[[package]]
+name = "kfnetlist"
+version = "0.2.2"
+source = { registry = "https://pypi.org/simple" }
+sdist = { url = "https://files.pythonhosted.org/packages/d2/80/6c1ec7ba4160c61ffaf710943fc25cc1b096ebe50233edf20f8258fd5a8d/kfnetlist-0.2.2.tar.gz", hash = "sha256:9ae38fc262867daa9d06cbda3efff3f1c00504227480d4ab92c379bf0d13b84e", size = 184421, upload-time = "2026-07-13T07:37:03.628Z" }
+wheels = [
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+    { url = "https://files.pythonhosted.org/packages/e1/0d/b89f0ebaa30d46b14e2fdfbecb7a51afadc51913822209794f938140abaf/kfnetlist-0.2.2-cp312-abi3-macosx_11_0_arm64.whl", hash = "sha256:fbaafd1cac298fa5b05ade6d5d764d363f9d1d5314428e876eeda1afac3c5a3c", size = 572532, upload-time = "2026-07-13T07:36:58.142Z" },
+    { url = "https://files.pythonhosted.org/packages/12/f6/da7b9274d1ce01597fc38cdaf01d152e283f99e9420877a10ca8a28c5708/kfnetlist-0.2.2-cp312-abi3-manylinux_2_17_aarch64.manylinux2014_aarch64.whl", hash = "sha256:0d9f0558537d8f53dcef81395f43b32aec525a812ee29b8b5b552739d0a8e2c4", size = 588358, upload-time = "2026-07-13T07:36:59.555Z" },
+    { url = "https://files.pythonhosted.org/packages/f4/ec/668945d0c21c9eb5fa64efcf52cd98fafdda72e3edbbe3458e7cb8a96001/kfnetlist-0.2.2-cp312-abi3-manylinux_2_17_x86_64.manylinux2014_x86_64.whl", hash = "sha256:3c72a1e26a72a4e3d0b57cc63f6a7c60b47b7397122147a0a5c044d8a0a15aea", size = 608655, upload-time = "2026-07-13T07:37:00.987Z" },
+    { url = "https://files.pythonhosted.org/packages/3b/46/ef0e5a0c31dd1861ee5b8fed042ed705ae08f27aceb55cb3fd87cdf40e88/kfnetlist-0.2.2-cp312-abi3-win_amd64.whl", hash = "sha256:6788a491686aac13c59c2de3ba2721b6495fc68b13b98ddc0fa81ca1d30f8a2b", size = 496245, upload-time = "2026-07-13T07:37:02.262Z" },
+]
+
 [[package]]
 name = "kiwisolver"
 version = "1.5.0"
@@ -2238,6 +2308,21 @@ wheels = [
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 ]
 
+[[package]]
+name = "lineax"
+version = "0.1.0"
+source = { registry = "https://pypi.org/simple" }
+dependencies = [
+    { name = "equinox" },
+    { name = "jax" },
+    { name = "jaxtyping" },
+    { name = "typing-extensions" },
+]
+sdist = { url = "https://files.pythonhosted.org/packages/35/d6/4e28416a6fe58dd6bc7565b1ffa330f4d0ba7d74212642b1b734c511299e/lineax-0.1.0.tar.gz", hash = "sha256:5f1a8f060142af2cdbf7d66b99e8d3071c3aa734b677df6339df4b4c4c0554d2", size = 50209, upload-time = "2026-01-27T21:17:26.652Z" }
+wheels = [
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+]
+
 [[package]]
 name = "locket"
 version = "1.0.0"
@@ -3020,6 +3105,22 @@ wheels = [
     { url = "https://files.pythonhosted.org/packages/8a/69/6a93d8600c339d7687a05857c7907bd4dd8cf88691a5ea106d7a50af90a1/optax-0.2.8-py3-none-any.whl", hash = "sha256:e3ca2d36c99daab1800ae9dbc0545034382d6bc780b24d969e1b0df65fa31cb4", size = 402960, upload-time = "2026-03-20T23:30:03.886Z" },
 ]
 
+[[package]]
+name = "optimistix"
+version = "0.1.0"
+source = { registry = "https://pypi.org/simple" }
+dependencies = [
+    { name = "equinox" },
+    { name = "jax" },
+    { name = "jaxtyping" },
+    { name = "lineax" },
+    { name = "typing-extensions" },
+]
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+wheels = [
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+]
+
 [[package]]
 name = "orderly-set"
 version = "5.5.0"