dev update

Author: ndbroadbent

DEVELOPMENT.md

@@ -1,5 +1,15 @@
 # Development Guidelines
 
+# Setup
+
+Install Watchman (used by Sorbet):
+
+```bash
+brew install watchman
+```
+
+For other platforms: https://facebook.github.io/watchman/docs/install.html
+
 ## Code Style and Conventions
 
 ### Module References

Gemfile

@@ -44,8 +44,8 @@ group :development, :test do
   gem 'rspec-sorbet-types', '~> 0.3.0'
   gem 'rubocop', '~> 1.21'
   gem 'rubocop-rspec', '~> 2.11'
+  gem 'solargraph'
   gem 'sorbet', '~> 0.5'
   gem 'sorbet-runtime', '~> 0.5.11874'
   gem 'tapioca', '~> 0.16.0'
-  gem 'watchman'
 end