diff --git a/README.md b/README.md
index 19ade51..db4ca04 100644
--- a/README.md
+++ b/README.md
@@ -148,6 +148,12 @@ ckanext.editable_config.options.blacklist = ckan.site_title ckan.site_descriptio
 # (optional, default: 0)
 ckanext.editable_config.charge_timeout = 10
 
+# Additional validators that are used when config option overrides are
+# applied. Use this option if CKAN validators are not strict enough and you
+# see the way to break the application by providing valid values for options.
+# (optional, default: {})
+ckanext.editable_config.additional_validators = {"ckan.site_title": "less_than_100 do_not_contain_exclamation_mark"}
+
 # Remove "Config" tab from CKAN's Admin UI.
 # (optional, default: false)
 ckanext.editable_config.disable_admin_config_tab = True
diff --git a/ckanext/editable_config/config.py b/ckanext/editable_config/config.py
index 1f0c50a..72070b6 100644
--- a/ckanext/editable_config/config.py
+++ b/ckanext/editable_config/config.py
@@ -8,6 +8,7 @@
 CHARGE_TIMEOUT = "ckanext.editable_config.charge_timeout"
 DISABLE_CONFIG_TAB = "ckanext.editable_config.disable_admin_config_tab"
 CONVERT_CORE_OVERRIDES = "ckanext.editable_config.convert_core_overrides"
+ADDITIONAL_VALIDATORS = "ckanext.editable_config.additional_validators"
 
 
 def extra_editable() -> list[str]:
@@ -32,3 +33,7 @@ def disable_admin_config_tab() -> bool:
 
 def convert_core_overrides() -> bool:
     return tk.config[CONVERT_CORE_OVERRIDES]
+
+
+def additional_validators() -> dict[str, str]:
+    return tk.config[ADDITIONAL_VALIDATORS]
diff --git a/ckanext/editable_config/config_declaration.yaml b/ckanext/editable_config/config_declaration.yaml
index 59aa8a2..ce00493 100644
--- a/ckanext/editable_config/config_declaration.yaml
+++ b/ckanext/editable_config/config_declaration.yaml
@@ -47,6 +47,16 @@ groups:
           may not be visible immediately - you'll have to wait `charge_timeout`
           seconds in worst case.
 
+      - key: ckanext.editable_config.additional_validators
+        example: '{"ckan.site_title": "less_than_100 do_not_contain_exclamation_mark"}'
+        default: {}
+        validators: convert_to_json_if_string dict_only
+        description: |
+          Additional validators that are used when config option overrides are
+          applied. Use this option if CKAN validators are not strict enough and
+          you see the way to break the application by providing valid values
+          for options.
+
       - key: ckanext.editable_config.disable_admin_config_tab
         type: bool
         example: true
diff --git a/ckanext/editable_config/plugin.py b/ckanext/editable_config/plugin.py
index 8387bf5..4bc75e3 100644
--- a/ckanext/editable_config/plugin.py
+++ b/ckanext/editable_config/plugin.py
@@ -55,6 +55,16 @@ def update_config(self, config_: CKANConfig):
 
                 cd[key].flags &= ~Flag.editable
 
+        self._add_validators(config.additional_validators())
+
+    def _add_validators(self, validators: dict[str, str]):
+        for key, names in validators.items():
+            if key not in cd:
+                log.warning("%s is not declared", key)
+                continue
+            option = cd[Key.from_string(key)]
+            option.append_validators(names)
+
     def _update_editable_flag(self, keys: list[str], enable: bool):
         for key in keys:
             if key not in cd:
diff --git a/ckanext/editable_config/tests/logic/test_action.py b/ckanext/editable_config/tests/logic/test_action.py
index 3fa6ced..b51a7a8 100644
--- a/ckanext/editable_config/tests/logic/test_action.py
+++ b/ckanext/editable_config/tests/logic/test_action.py
@@ -80,6 +80,23 @@ def test_valid(self, faker, ckan_config):
         call_action("editable_config_change", options={"ckan.site_title": title})
         assert ckan_config["ckan.site_title"] == title
 
+    @pytest.mark.ckan_config(config.EXTRA_EDITABLE, "ckan.datasets_per_page")
+    @pytest.mark.ckan_config(
+        config.ADDITIONAL_VALIDATORS,
+        {"ckan.datasets_per_page": "is_positive_integer"},
+    )
+    def test_additional_validators(self):
+        """Options are validated"""
+        with pytest.raises(tk.ValidationError):
+            call_action(
+                "editable_config_change",
+                options={"ckan.datasets_per_page": -1},
+            )
+        call_action(
+            "editable_config_change",
+            options={"ckan.datasets_per_page": 1},
+        )
+
 
 @pytest.mark.usefixtures("with_plugins", "non_clean_db", "with_autoclean")
 class TestRevert: