diff --git a/pyproject.toml b/pyproject.toml
index 1a11c32..f632e71 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,3 +1,7 @@
+[build-system]
+requires = ["poetry-core"]
+build-backend = "poetry.core.masonry.api"
+
 [tool.poetry]
 name = "conflator"
 version = "0.1.8"
@@ -9,19 +13,14 @@ repository = "https://github.com/ecmwf/conflator/"
 
 [tool.poetry.dependencies]
 python = ">3.9"
-pydantic = ">2.0"
+pydantic = ">=2.9"
 rich-argparse = ">1.0"
 pyyaml = ">6.0"
 
-
 [tool.poetry.group.dev.dependencies]
 mypy = ">1.8.0"
 ruff = ">0.2.0"
 
-[build-system]
-requires = ["poetry-core"]
-build-backend = "poetry.core.masonry.api"
-
 [tool.ruff]
 line-length = 120
 lint.extend-select = ["I"]
diff --git a/requirements.txt b/requirements.txt
deleted file mode 100644
index 72754b5..0000000
--- a/requirements.txt
+++ /dev/null
@@ -1,4 +0,0 @@
-pydantic==2.6.0
-pydantic_core==2.16.1
-rich==13.7.0
-rich-argparse==1.4.0
\ No newline at end of file
diff --git a/tests/requirements_test.txt b/tests/requirements_test.txt
deleted file mode 100644
index 5d26cde..0000000
--- a/tests/requirements_test.txt
+++ /dev/null
@@ -1,3 +0,0 @@
--r ../requirements.txt
-annotated-types==0.6.0
-pytest==8.0.0
\ No newline at end of file
diff --git a/tests/test_conflator_functions.py b/tests/test_conflator_functions.py
index 0399e5a..e27beec 100644
--- a/tests/test_conflator_functions.py
+++ b/tests/test_conflator_functions.py
@@ -131,7 +131,7 @@ class NewConfig(ConfigModel):
                         "type": "string",
                     },
                     "nested_key": {
-                        "allOf": [{"$ref": "#/$defs/NestedConfig"}],
+                        "$ref": "#/$defs/NestedConfig",
                         "default": {"key": "test"},
                     },
                 },
diff --git a/tests/test_subclasses.py b/tests/test_subclasses.py
index d27f49a..ee784c3 100644
--- a/tests/test_subclasses.py
+++ b/tests/test_subclasses.py
@@ -10,7 +10,6 @@
 
 
 class Action(ConfigModel):
-    model_config = ConfigDict(extra="forbid")
     model_config = ConfigDict(extra="forbid")
     name: str
 
@@ -67,14 +66,6 @@ def get(self, target):
         ]
     )
 )
-action_subclasses = tuple(
-    set(Subclasses().get(Action).values())
-    - set(
-        [
-            Action,
-        ]
-    )
-)
 
 # Constuct a union type out of the subclasses
 # Field(discriminator="name") tells pydantic to look at the name
@@ -83,9 +74,7 @@ def get(self, target):
 
 
 class Config(ConfigModel):
-    actions: list[action_subclasses_union] = Field(discriminator="name")
-
-    actions: list[action_subclasses_union] = Field(discriminator="name")
+    actions: list[action_subclasses_union]
 
 
 def test_subclasses():
diff --git a/tox.ini b/tox.ini
index d8c58d1..5acee76 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,24 +1,3 @@
-[tox]
-env_list = py{39,310,311,312}
-minversion = 4.12.1
-
-[testenv]
-description = run the tests with pytest
-package = wheel
-wheel_build_env = .pkg
-deps =
-    pytest>=6
-commands =
-    pytest {tty:--color=yes} {posargs}
-
-# Provide a mapping between tox envs and github actions python envs
-[gh-actions]
-python =
-    3.9: py39
-    3.10: py310
-    3.11: py311
-    3.12: py312
-
 [flake8]
 max-line-length = 120
 exclude = .*