diff --git a/freeqdsk/_fileutils.py b/freeqdsk/_fileutils.py
index d8b4065..61fe6c3 100644
--- a/freeqdsk/_fileutils.py
+++ b/freeqdsk/_fileutils.py
@@ -15,7 +15,8 @@
 
 import fortranformat as ff
 import numpy as np
-from numpy.typing import ArrayLike
+
+from ._typing import FloatArray, ArrayLike
 
 
 def f2s(f: float) -> str:
@@ -145,7 +146,7 @@ def write_1d(values: Iterable[Any], out: ChunkOutput) -> None:
     out.newline()
 
 
-def write_2d(values: ArrayLike, out: ChunkOutput) -> None:
+def write_2d(values: FloatArray, out: ChunkOutput) -> None:
     r"""
     Writes a 2D array to a ChunkOutput file handle.
 
diff --git a/freeqdsk/_typing.py b/freeqdsk/_typing.py
new file mode 100644
index 0000000..437b2c2
--- /dev/null
+++ b/freeqdsk/_typing.py
@@ -0,0 +1,20 @@
+"""Some type aliases, mostly for hinting about arrays of
+numbers. `numpy.typing.ArrayLike` covers anything that can be
+converted to an array of any type, and we mostly want to restrict to
+arrays of floats.
+
+"""
+
+from typing import Union, Any, List
+import numpy as np
+
+try:
+    from numpy.typing import NDArray
+
+    float_ = np.floating[Any]
+    FloatArray = NDArray[np.floating[Any]]
+except ImportError:
+    float_ = float  # type: ignore
+    FloatArray = np.ndarray  # type: ignore
+
+ArrayLike = Union[int, float, float_, FloatArray, List[float_]]
diff --git a/freeqdsk/aeqdsk.py b/freeqdsk/aeqdsk.py
index 74c7a3a..0b77c14 100644
--- a/freeqdsk/aeqdsk.py
+++ b/freeqdsk/aeqdsk.py
@@ -14,8 +14,8 @@
 from typing import Dict, Optional, TextIO, Union
 
 import numpy as np
-from numpy.typing import ArrayLike
 
+from ._typing import ArrayLike
 from ._fileutils import read_array, write_array, write_line
 
 
diff --git a/freeqdsk/geqdsk.py b/freeqdsk/geqdsk.py
index 927bf29..5d96679 100644
--- a/freeqdsk/geqdsk.py
+++ b/freeqdsk/geqdsk.py
@@ -142,8 +142,8 @@
 from typing import Dict, Optional, TextIO, Union
 
 import numpy as np
-from numpy.typing import ArrayLike
 
+from ._typing import ArrayLike
 from ._fileutils import read_array, read_line, write_array, write_line