osu! Ripple

GitHub is used to mirror our code, and in certain subprojects also to publish the code directly and allow PRs/issues. GitHub

Gitea is where our code lives and shines. We love self-hosted and would rather not pay too much money for GitHub private repos, so we just use our own Gitea instance. Gitea

We use Semantic UI for our frotend. A heavily customised version of it, but still Semantic UI under the hood. Semantic UI

MariaDB is used the same way as MySQL, except that MariaDB is used on our arch-based servers. MariaDB

Discord is used for all the discussions with our community, and discussions between our entire staff (including Community Managers, Chat Moderators and BATs). We also use a Discord bot we developed to deploy new code to the server. Discord

Long-lived data is stored in MySQL, period. Everything from users, to scores, to beatmaps, anything. MySQL

Donations are processed through PayPal, mostly. So it's a pretty indespensable tool, as it's our main source of income. PayPal

Mails from the website frontend are sent through Mailgun, mainly because of the free plan of 10,000 emails which perfectly suits us. Mailgun

Trello is the core of our workflow. All tasks to be done go on Trello, and whenever you have to work on something, you go on Trello to check out what you could work on. And it works perfectly for us. Trello

Redis is probably the single piece of software we love the most. We just love its simplicity, speed and we use it for caching data, storing user sessions, and making leaderboards. It just works perfectly for us. Redis