Just a tiny thing (or maybe just a matter of taste):

In Chapter 10 "Easy File Slurping", you use this idiom for slurping:

    my $file = do { local $/ = <$fh> };
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For me the assignment to the localized $/ (that is done just so that the do-block returns the file-content) is confusing.

Clearer (for me):

    my $file = do { local $/; <$fh> };
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