This extension is a PHP binding for Google LevelDB Formula was removed
Last versions were
php55-leveldb requires the following formulae to be installed:
autoconf 2.69 Automatic configure script builder
leveldb 1.20_2 Key-value storage library with ordered mapping

Recent formula history

Mike McQuaid Deprecate tap.
ilovezfs php55-leveldb: bottle revision to rebuild.
Andreas Braun Add description for leveldb formula
Andy Blyler php55-leveldb: convert from sha1 to sha256
Andy Blyler fix style issues

Formula code at GitHub