I am not sure about that. Files are also pickled.

is there no incompatibility in loading joblib pickles with pickle.load?

Short answer no.

Longer answer: starting in joblib 0.10 (released in July 2016) files produced by joblib.dump can not be read with pickle.load if the dumped object "contains" a numpy array. If the dumped object does not "contain" a numpy array, then it is a standard Python pickle and can be read with pickle.load

import pickle
import joblib
import numpy as np

filename = '/tmp/test.pkl'
joblib.dump([1, 2, 3], filename)
pickle.load(open(filename, 'rb'))  # works fine
joblib.dump(np.array([1, 2, 3]), filename)
pickle.load(open(filename, 'rb'))  # UnpicklingError: invalid load key, '\x01'.

To sum up, I am fine with changing the extension in the example, maybe .jbl rather than .joblib?

is there no incompatibility in loading joblib pickles with pickle.load?

Short answer no.

To summarize the triple negation - it's not strictly compatible :)

maybe .jbl rather than .joblib?

https://datatypes.net/open-jbl-files: .jbl seems to be an already existing extension.

I should have guessed: any combination of 3 letters is already taken with high probability ;-). Let's go for .joblib then!

Please also update other similar places in the repo (e.g., doc/tutorial/basic/tutorial.rst)

LGTM as well. I did the change in the master branch of joblib. Let's merge this.

I pushed a similar change in 066b501 for doc/tutorial/basic/tutorial.rst.

Sorry I'm not familiar with the doc site publishing workflow -- is there any additional actions for me to take to reflect the changes on the website? It is still showing the pre-merge content.

http://scikit-learn.org/stable/modules/model_persistence.html

Look at /dev rather than /stable. We will release real soon now...