How to install multiple Drush versions on the account

It requires a lot of resources, so double check if you have enough

The latest dev version to drush/ folder:

mkdir drush
cd drush
curl -sS | php
./composer.phar require drush/drush:dev-master
echo "alias drush='~/drush/vendor/bin/drush'" >> .bashrc
source .bashrc

Drush 9 version

mkdir drush9
cd drush9
curl -sS
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