diff --git a/docs/source/conf.py b/docs/source/conf.py
index 0604cedd..ad29b28d 100644
--- a/docs/source/conf.py
+++ b/docs/source/conf.py
@@ -133,7 +133,7 @@ class VersionVisitor(ast.NodeVisitor):
         def visit_Assign(self, node):
             for target in node.targets:
                 if getattr(target, 'id', None) == '__version__':
-                    self.version = node.value.s
+                    self.version = node.value.value
 
     visitor = VersionVisitor()
     visitor.visit(pt)
diff --git a/tests/test_docs_conf.py b/tests/test_docs_conf.py
new file mode 100644
index 00000000..6f072b8a
--- /dev/null
+++ b/tests/test_docs_conf.py
@@ -0,0 +1,31 @@
+"""Tests for helpers defined in the Sphinx configuration."""
+import ast
+from os.path import dirname, exists, join
+
+import pytest
+
+CONF_FPATH = join(dirname(dirname(__file__)), 'docs', 'source', 'conf.py')
+
+
+def _load_parse_version():
+    """Extract ``parse_version`` from ``conf.py`` without importing sphinx."""
+    if not exists(CONF_FPATH):
+        pytest.skip('docs/source/conf.py is not available')
+    tree = ast.parse(open(CONF_FPATH, 'r').read())
+    for node in tree.body:
+        if isinstance(node, ast.FunctionDef) and node.name == 'parse_version':
+            ns = {'exists': exists, 'join': join, 'dirname': dirname}
+            exec(compile(ast.Module([node], []), CONF_FPATH, 'exec'), ns)
+            return ns['parse_version']
+    pytest.skip('conf.py does not define parse_version')
+
+
+def test_parse_version(tmp_path):
+    """``parse_version`` works on Python 3.14, where ``ast.Constant.s`` is gone.
+
+    See https://github.com/pyutils/line_profiler/issues/429
+    """
+    parse_version = _load_parse_version()
+    fpath = tmp_path / 'mod.py'
+    fpath.write_text("__version__ = '1.2.3'\n")
+    assert parse_version(str(fpath)) == '1.2.3'