SILC conferencing client Formula was removed
Last version was

Revision: 1

silc-client requires the following formulae to be installed:
pkg-config 0.29.2 Manage compile and link flags for libraries
glib 2.56.1 Core application library for C
openssl 1.0.2o_1 SSL/TLS cryptography library

Recent formula history

Mike McQuaid Deprecate Homebrew/boneyard. (#314)
ilovezfs silc-client: migrate from core (#289)

Formula code at GitHub