diff --git a/uv.lock b/uv.lock
index 22e9a6e0..9d49ce12 100644
--- a/uv.lock
+++ b/uv.lock
@@ -1,5 +1,5 @@
 version = 1
-revision = 2
+revision = 3
 requires-python = ">=3.9"
 resolution-markers = [
     "python_full_version >= '3.13'",
@@ -739,10 +739,11 @@ wheels = [
 
 [[package]]
 name = "formulaic"
-version = "1.1.1"
+version = "1.2.1"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "interface-meta" },
+    { name = "narwhals" },
     { name = "numpy", version = "2.0.2", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version < '3.10'" },
     { name = "numpy", version = "2.2.6", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version >= '3.10'" },
     { name = "pandas" },
@@ -751,9 +752,9 @@ dependencies = [
     { name = "typing-extensions" },
     { name = "wrapt" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/5c/30/03b5e3bb62374db3f665ca3020fdfc4304e98ceeaaa9dcd7a47a6b574ebf/formulaic-1.1.1.tar.gz", hash = "sha256:ddf80e4bef976dd99698aa27512015276c7b86c314b601ae6fd360c7741b7231", size = 652602, upload-time = "2024-12-20T19:37:04.66Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/6a/8b/8038d2af289a5cc194fa0a255fe964a1a04e0e6ca4426aed8841a4b571e6/formulaic-1.2.1.tar.gz", hash = "sha256:dc79476baa2d811b35798893eb2f2c1e51edee8d7a9c1429b400e56f4e0beccc", size = 655266, upload-time = "2025-09-21T05:27:31.488Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/d2/c2/a34097e53efe70a538ae97574ff9e9866e60fc1c792c19da5fd6b56ce7b5/formulaic-1.1.1-py3-none-any.whl", hash = "sha256:bbb7e38f99e4bcdc62cb0a6a818ad33b370b4e98e9e4f0b276561448482c8268", size = 115718, upload-time = "2024-12-20T19:37:07.055Z" },
+    { url = "https://files.pythonhosted.org/packages/1a/9d/c2c8b51b32f829a16fe042db30ad1dcef7947bf1dcf77c2cfd7b6f37b83a/formulaic-1.2.1-py3-none-any.whl", hash = "sha256:661d6d2467aa961b9afb3a1e2a187494239793c63eb729e422d1307afa98b43b", size = 117290, upload-time = "2025-09-21T05:27:30.025Z" },
 ]
 
 [[package]]