diff --git a/reasoning_gym/code/codeio.py b/reasoning_gym/code/codeio.py
new file mode 100644
index 00000000..7ecb20cf
--- /dev/null
+++ b/reasoning_gym/code/codeio.py
@@ -0,0 +1,68 @@
+from dataclasses import dataclass
+from random import Random
+from typing import Any, Optional
+
+from ..factory import ProceduralDataset, register_dataset
+
+
+@dataclass
+class CodeIOConfig:
+    """Configuration for BF task generation"""
+
+    seed: Optional[int] = None
+    size: int = 500
+
+    def validate(self) -> None:
+        """Validate configuration parameters"""
+        pass
+
+
+class CodeIODataset(ProceduralDataset):
+    def __init__(self, config: CodeIOConfig):
+        super().__init__(config=config, seed=config.seed, size=config.size)
+
+    def __len__(self) -> int:
+        return self.config.size
+
+    def __iter__(self):
+        self._current_idx = 0
+        return self
+
+    def __next__(self):
+        if self._current_idx >= self.config.size:
+            raise StopIteration
+        item = self[self._current_idx]
+        self._current_idx += 1
+        return item
+
+    def __getitem__(self, idx: int) -> dict:
+        """Generate a single mini sudoku puzzle"""
+        rng = Random(self.seed + idx)
+
+        # TODO
+        question = ""
+        solution = ""
+
+        return {
+            "question": question,
+            "answer": solution,
+            "metadata": {},
+        }
+
+    def score_answer(self, answer: Optional[str], entry: dict[str, Any]) -> float:
+        oracle_answer = entry["answer"].strip()
+        reward = 0.0
+        if answer is not None and len(answer) > 0:
+            answer = answer.strip()
+            if answer == oracle_answer:
+                reward = 1.0
+            elif oracle_answer in answer:
+                reward = len(oracle_answer) / len(answer)
+            else:
+                reward = 0.01
+
+        return reward
+
+
+# Register the dataset
+register_dataset("codeio", CodeIODataset, CodeIOConfig)