diff --git a/deepsensor/data/loader.py b/deepsensor/data/loader.py
index 17ef8de9..bce3fd39 100644
--- a/deepsensor/data/loader.py
+++ b/deepsensor/data/loader.py
@@ -18,7 +18,7 @@ class TaskLoader:
 
     def __init__(
         self,
-        task_loader_ID: str | None = None,
+        task_loader_ID: Union[str, None] = None,
         context: Union[
             xr.DataArray,
             xr.Dataset,
@@ -35,7 +35,7 @@ def __init__(
         ] = None,
         aux_at_contexts: Union[xr.DataArray, xr.Dataset, str] = None,
         aux_at_targets: Union[xr.DataArray, xr.Dataset, str] = None,
-        links: List[Tuple[int, int]] | None = None,
+        links: Union[List[Tuple[int, int]], None] = None,
         context_delta_t: Union[int, List[int]] = 0,
         target_delta_t: Union[int, List[int]] = 0,
         time_freq: str = "D",
diff --git a/deepsensor/data/processor.py b/deepsensor/data/processor.py
index d3f106d2..841104fe 100644
--- a/deepsensor/data/processor.py
+++ b/deepsensor/data/processor.py
@@ -20,12 +20,12 @@ class DataProcessor:
 
     def __init__(
         self,
-        folder: str | None = None,
+        folder: Union[str, None] = None,
         time_name: str = "time",
         x1_name: str = "x1",
         x2_name: str = "x2",
-        x1_map: tuple | None = None,
-        x2_map: tuple | None = None,
+        x1_map: Union[tuple, None] = None,
+        x2_map: Union[tuple, None] = None,
         deepcopy: bool = True,
         verbose: bool = False,
     ):
diff --git a/deepsensor/model/defaults.py b/deepsensor/model/defaults.py
index ddd1b5af..e85088dc 100644
--- a/deepsensor/model/defaults.py
+++ b/deepsensor/model/defaults.py
@@ -9,6 +9,8 @@
     compute_pandas_data_resolution,
 )
 
+from typing import List
+
 
 def gen_ppu(task_loader: TaskLoader) -> int:
     """Computes data-informed settings for the model's internal grid density (ppu, points per unit)
@@ -55,7 +57,7 @@ def gen_decoder_scale(model_ppu: int) -> float:
     return 1 / model_ppu
 
 
-def gen_encoder_scales(model_ppu: int, task_loader: TaskLoader) -> list[float]:
+def gen_encoder_scales(model_ppu: int, task_loader: TaskLoader) -> List[float]:
     """Computes data-informed settings for the encoder SetConv scale for each context set
 
     This sets the length scale of the Gaussian basis functions used to encode the context sets.