YouTrack is an issue tracker and project management tool from JetBrains, aimed at software teams and other teams that want to track work, bugs and tasks. It runs in the browser and offers a query language for searching, a REST API and integrations with GitHub, GitLab, Bitbucket, Slack and JetBrains IDEs, among others. JetBrains offers two variants: YouTrack Cloud and YouTrack Server, which you install on your own server. The server product is distributed as a Docker container for evaluation and production use.
JetBrains s.r.o. is based in Prague, Czech Republic, and according to its privacy notice is the lead data controller; the company names the EU as the default location for customers' personal data. YouTrack is proprietary software and therefore not open source. With the self-hosted option, your organisation decides where the data is stored and who can access it, while licensing and updates remain with a European vendor. If you choose the cloud service instead, the hosting location depends on what JetBrains offers, so check this beforehand.