On your Jira dashboard, go to Jira Administration ➜ Manage apps.
The Find new apps page is displayed. Search the Marketplace with ‘
bigbrassband‘ or ‘
git‘ search phrase.
Buy the app or start the free trial for 30 days.
Login to your Jira account, if required, to proceed installation of the app. The license key is automatically configured into the app configuration for free trial licenses. For purchased license keys, see Managing license key.
More on Git Integration for Jira installation
Installation via Jira Plugin Manager (this page)