How do you get git-annex installed?

[[!poll expandable=yes open=yes 6 "From a prebuilt version on this website" 2 "I build from source" 5 "I install the version provided by my OS distributor" 0 "I don't know; it was installed for me" 1 "homebrew -> cabal" 1 "from the ubuntu PPA"]]

If you install it using different methods at different times, pick the
method you use most frequently.

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