diff --git a/apax/nodes/model.py b/apax/nodes/model.py
index 773f7e6c..f9323362 100644
--- a/apax/nodes/model.py
+++ b/apax/nodes/model.py
@@ -47,9 +47,12 @@ class Apax(ApaxBase):
         verbosity of logging during training
     """
 
-    data: list[ase.Atoms] = zntrack.deps()
+    data: list[ase.Atoms] | None = zntrack.deps()
+    data_path: str | pathlib.Path | None = zntrack.deps_path(None)
+
     config: str = zntrack.params_path()
-    validation_data: list[ase.Atoms] = zntrack.deps()
+    validation_data: list[ase.Atoms] | None = zntrack.deps()
+    validation_data_path: str | pathlib.Path | None = zntrack.deps_path(None)
     model: t.Optional[ApaxBase] = zntrack.deps(None)
     nl_skin: float = zntrack.params(0.5)
     log_level: str = zntrack.params("info")
@@ -61,6 +64,16 @@ class Apax(ApaxBase):
 
     metrics: dict = zntrack.metrics()
 
+    def __post_init__(self):
+        super().__post_init__()
+
+        if self.data is not None and self.data_path is not None:
+            raise ValueError("You can either provide `data` or `data_path`, not both.")
+        if self.validation_data is not None and self.validation_data_path is not None:
+            raise ValueError(
+                "You can either provide `validation_data` or `validation_data_path`, not both."
+            )
+
     @property
     def parameter(self) -> dict:
         parameter = yaml.safe_load(self.state.fs.read_text(self.config))
@@ -68,8 +81,12 @@ def parameter(self) -> dict:
         custom_parameters = {
             "directory": self.model_directory.as_posix(),
             "experiment": "",
-            "train_data_path": self.train_data_file.as_posix(),
-            "val_data_path": self.validation_data_file.as_posix(),
+            "train_data_path": self.train_data_file.as_posix()
+            if self.data is None
+            else self.data_path,
+            "val_data_path": self.validation_data_file.as_posix()
+            if self.validation_data is None
+            else self.validation_data_path,
         }
 
         if self.model is not None:
@@ -98,11 +115,18 @@ def run(self):
         """Primary method to run which executes all steps of the model training"""
 
         if not self.state.restarted:
-            train_db = znh5md.IO(self.train_data_file.as_posix())
-            train_db.extend(self.data)
-
-            val_db = znh5md.IO(self.validation_data_file.as_posix())
-            val_db.extend(self.validation_data)
+            if self.data is not None:
+                train_db = znh5md.IO(self.train_data_file.as_posix())
+                train_db.extend(self.data)
+            else:
+                self.train_data_file.write_text(f"Using {self.data_path} instead")
+            if self.validation_data is not None:
+                val_db = znh5md.IO(self.validation_data_file.as_posix())
+                val_db.extend(self.validation_data)
+            else:
+                self.validation_data_file.write_text(
+                    f"Using {self.validation_data_path} instead"
+                )
 
         csv_path = self.model_directory / "log.csv"
         if self.state.restarted and csv_path.is_file():