diff --git a/visidata/loaders/npy.py b/visidata/loaders/npy.py
index 8003b2f7d..d9c9e46f8 100644
--- a/visidata/loaders/npy.py
+++ b/visidata/loaders/npy.py
@@ -14,7 +14,7 @@ def open_npz(vd, p):
 
 class NpySheet(Sheet):
     def iterload(self):
-        import numpy
+        vd.importExternal('numpy')
         if not hasattr(self, 'npy'):
             self.npy = numpy.load(str(self.source), encoding='bytes', **self.options.getall('npy_'))
         self.reloadCols()
@@ -47,12 +47,12 @@ class NpzSheet(vd.ZipSheet):
     ]
 
     def iterload(self):
-        import numpy
+        vd.importExternal('numpy')
         self.npz = numpy.load(str(self.source), encoding='bytes', **self.options.getall('npy_'))
         yield from Progress(self.npz.items())
 
     def openRow(self, row):
-        import numpy
+        vd.importExternal('numpy')
         tablename, tbl = row
         if isinstance(tbl, numpy.ndarray):
             return NpySheet(tablename, npy=tbl)
@@ -62,7 +62,7 @@ def openRow(self, row):
 
 @VisiData.api
 def save_npy(vd, p, sheet):
-    import numpy as np
+    np = vd.importExternal('numpy')
 
     dtype = []
 
diff --git a/visidata/loaders/pandas_freqtbl.py b/visidata/loaders/pandas_freqtbl.py
index c4af1e9ca..be37f5976 100644
--- a/visidata/loaders/pandas_freqtbl.py
+++ b/visidata/loaders/pandas_freqtbl.py
@@ -11,8 +11,8 @@ class DataFrameRowSliceAdapter:
     by visidata's selectRow implementation.
     """
     def __init__(self, df, mask):
-        import pandas as pd
-        import numpy as np
+        pd = vd.importExternal('pandas')
+        np = vd.importExternal('numpy')
         if not isinstance(df, pd.DataFrame):
             vd.fail('%s is not a dataframe' % type(df).__name__)
         if not isinstance(mask, pd.Series):