Find duplicate files based on content (NOT file names)

Current version

rdfind requires the following formula to be installed:
nettle 3.4 Low-level cryptographic library

Recent formula history

ilovezfs rdfind 1.3.5
ilovezfs rdfind: use refute_predicate instead of !File.exist?
ilovezfs rdfind: use assert_predicate instead of File.exist?
Tomasz Pajor rdfind: audit fixes
Rakesh update revision on upgrading to nettle 3

Formula code at GitHub