Why not use reticulate?

• When reading .npy files with {reticulate}, at some point in time, two (sometimes 3) copies of the data are made in memory: one in Python and one in R. This can be problematic for large files. With {grumpy}, only one copy of the data is made in memory.
• Reading data with {reticulate} requires a Python installation and additional python packages, which users in restricted environments may not have access to. {grumpy} is a pure R package with no external dependencies.