diff --git a/docs/conf.py b/docs/conf.py
index 8cfb8077..e3f7853a 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -87,6 +87,9 @@
 napoleon_use_rtype = True
 napoleon_use_ivar = True
 
+# temp use the old (Sphinx 8.2 and earlier, class-based) implementation
+autodoc_use_legacy_class_based = True
+
 # -- Options for HTML output -------------------------------------------------
 
 # The theme to use for HTML and HTML Help pages.  See the documentation for
diff --git a/pyproject.toml b/pyproject.toml
index 7e63ae50..48e02e44 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -47,7 +47,7 @@ dev = ["pre-commit>=2.12.1"]
 tests = ["pytest", "pytest-mock", "pytest-split", "pytest-cov", "types-setuptools"]
 docs = [
     "sphinx-copybutton==0.5.2",
-    "sphinx>=5,<9",
+    "sphinx>=5,<10",
     "sphinx_design==0.7.0",
     "myst-nb==1.4.0",
     "sphinx-book-theme==1.2.0",