diff --git a/pyproject.toml b/pyproject.toml
index 877e8269..de2621cd 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -3,12 +3,12 @@ requires = [
     "setuptools>=45",
     "setuptools_scm[toml]>=8.0.4,<9",
     'mypy==1.7.0',  # update mypy-requirements as well
-    "black>=19.10b0",
+    "black>=19.10b0,<23.12",
     "types-pkg_resources",
     "types-requests",
     "types-dataclasses",
     "importlib_resources>=1.4",  # equivalent to Python 3.9
-    "ruamel.yaml>= 0.12.4, != 0.16.6, < 0.18",
+    "ruamel.yaml>=0.17.6, < 0.19",
     "types-setuptools"
 ]
 build-backend = "setuptools.build_meta"
diff --git a/requirements.txt b/requirements.txt
index 2171d404..34b5eecd 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -3,7 +3,7 @@ ruamel.yaml >= 0.17.6, < 0.19
 rdflib>= 4.2.2, < 8.0.0
 mistune>=2.0.3,<2.1
 CacheControl[filecache]>= 0.11.7, < 0.14
-black<23.12
+black>=19.10b0,<23.12
 mypy_extensions
 importlib_resources>=1.4
 # ^^ equivalent to Python 3.9