From 3e64fa40ef16b1c57cb14f7778c1c1755194f640 Mon Sep 17 00:00:00 2001
From: Wen Kokke <wenkokke@users.noreply.github.com>
Date: Sun, 19 Jul 2020 19:06:50 +0100
Subject: [PATCH] Fix issue with ffi gem on MacOS.

---
 Gemfile | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Gemfile b/Gemfile
index 4ae04980..70f9fd15 100644
--- a/Gemfile
+++ b/Gemfile
@@ -8,6 +8,9 @@ group :development do
   gem 'guard'
   gem 'guard-shell'
   gem 'html-proofer'
+  # ffi-1.13.1 is broken on macos
+  # https://github.com/ffi/ffi/issues/791
+  gem 'ffi', '~> 1.12.2'
 end
 
 group :epub do