Bitcoin-Logo-300x300User /r/Nightshdr shows us how to build Bitcoin Classic on FreeBSD 10. See the link below for full instructions.

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# BUILDING BITCOIN CLASSIC ON FREEBSD #
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We use the ports tree to get going

 portsnap fetch
 portsnap update

You might need to install the openssl package

 pkg install openssl

Start building legacy, ONLY to satisfy build requirements

 cd /usr/ports/net-p2p/bitcoin-daemon/
 gmake (CTRL-C when it starts building Core)
 
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Full instructions: https://www.reddit.com/r/Bitcoin_Classic/comments/44ilow/build_classic_on_freebsd_10x/t1_d16u3gp