PHP wrapper to libgearman Formula was removed
Last versions were
php70-gearman requires the following formulae to be installed:
autoconf 2.69 Automatic configure script builder
gearman 1.1.18 Application framework to farm out work to other machines or processes

Recent formula history

ilovezfs php70: migrate to homebrew/core
Andreas Möller Fix: Update gearman for php70-gearman
Stephen Orr php70-gearman 2.0.1 (new formula)

Formula code at GitHub