proxychains suddenly stopped working
Uninstall proxychains-ng brew uninstall proxychains-ng.
proxychains-ng need Xcode 7.x to build, build with Xcode 8 will cause this problem. Run xcode-select to change Xcode command line tool version, in my case sudo xcode-select -s /Applications/Xcode7.app/Contents/Developer.
Reinstall proxychains-ng brew install proxychains-ng.