diff --git a/.rodare.json b/.rodare.json
index dd52734dea..d405ca4a24 100644
--- a/.rodare.json
+++ b/.rodare.json
@@ -96,6 +96,11 @@
             "name": "Ganyushin, Dmitry",
             "orcid": "0000-0001-7337-2161",
             "type": "Other"
+        },
+        {
+            "affiliation": "NVIDIA",
+            "name": "Kirkham, John",
+            "type": "Other"
         }
     ],
     "title": "C++ & Python API for Scientific I/O with openPMD",
diff --git a/README.md b/README.md
index eb762fa78f..b2e83598b4 100644
--- a/README.md
+++ b/README.md
@@ -401,6 +401,8 @@ Further thanks go to improvements and contributions from:
   report on NVCC warnings
 * [Dmitry Ganyushin (ORNL)](https://github.com/dmitry-ganyushin):
   Dask dataframe support
+* [John Kirkham (NVIDIA)](https://github.com/jakirkham):
+  Dask guidance & reviews
 
 ### Grants
 
diff --git a/src/binding/python/openpmd_api/DaskDataFrame.py b/src/binding/python/openpmd_api/DaskDataFrame.py
index fecdcc27f4..b942fa86fa 100644
--- a/src/binding/python/openpmd_api/DaskDataFrame.py
+++ b/src/binding/python/openpmd_api/DaskDataFrame.py
@@ -2,7 +2,7 @@
 This file is part of the openPMD-api.
 
 Copyright 2021 openPMD contributors
-Authors: Axel Huebl, Dmitry Ganyushin
+Authors: Axel Huebl, Dmitry Ganyushin, John Kirkham
 License: LGPLv3+
 """
 import numpy as np
@@ -19,6 +19,11 @@
     found_pandas = False
 
 
+def read_chunk_to_df(species, chunk):
+    stride = np.s_[chunk.offset[0]:chunk.extent[0]]
+    return species.to_df(stride)
+
+
 def particles_to_daskdataframe(particle_species):
     """
     Load all records of a particle species into a Dask DataFrame.
@@ -74,13 +79,9 @@ def particles_to_daskdataframe(particle_species):
             if chunks:
                 break
 
-    def read_chunk(species, chunk):
-        stride = np.s_[chunk.offset[0]:chunk.extent[0]]
-        return species.to_df(stride)
-
     # merge DataFrames
     dfs = [
-        delayed(read_chunk)(particle_species, chunk) for chunk in chunks
+        delayed(read_chunk_to_df)(particle_species, chunk) for chunk in chunks
     ]
     df = dd.from_delayed(dfs)