diff --git a/CHANGELOG.md b/CHANGELOG.md
index 58c8b13..a1a0f94 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ## Unreleased
 ### Added
 - AffineCipher.invert method to obtain the inverse cipher
+### Changed
+- Depend on cython~=3.0
 
 
 ## [0.0.3] - 2024-10-14
diff --git a/pyproject.toml b/pyproject.toml
index 8b4c3b0..22e616f 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -40,7 +40,7 @@ Issues = "https://github.com/jfolz/shufflish/issues"
 Changelog = "https://github.com/jfolz/shufflish/blob/main/CHANGELOG.md"
 
 [build-system]
-requires = ["setuptools>=50.0.3", "wheel", "cython~=3.0.0", "setuptools_scm"]
+requires = ["setuptools>=50.0.3", "wheel", "cython~=3.0", "setuptools_scm"]
 build-backend = "setuptools.build_meta"
 
 [tool.setuptools_scm]
diff --git a/shufflish/_affine.pyx b/shufflish/_affine.pyx
index 50ca20f..97b84bc 100644
--- a/shufflish/_affine.pyx
+++ b/shufflish/_affine.pyx
@@ -123,6 +123,16 @@ cdef class AffineCipher:
             self.params.post_offset,
         ))
 
+    def __eq__(self, other):
+        if not isinstance(other, AffineCipher):
+            return False
+        cdef AffineCipher other_ = other
+        cdef affineCipherParameters oparams = other_.params
+        return self.params.domain == oparams.domain \
+           and self.params.prime == oparams.prime \
+           and self.params.pre_offset == oparams.pre_offset \
+           and self.params.post_offset == oparams.post_offset
+
     def parameters(self):
         """
         Returns the affine parameters as tuple
@@ -135,16 +145,6 @@ cdef class AffineCipher:
             self.params.post_offset,
         )
 
-    def __eq__(self, other):
-        if not isinstance(other, AffineCipher):
-            return False
-        cdef AffineCipher other_ = other
-        cdef affineCipherParameters oparams = other_.params
-        return self.params.domain == oparams.domain \
-           and self.params.prime == oparams.prime \
-           and self.params.pre_offset == oparams.pre_offset \
-           and self.params.post_offset == oparams.post_offset
-
     def invert(self) -> AffineCipher:
         """
         Returns the inverse of this affine cipher, i.e.,