atlassian.comは安全ですか？

A good bug database (JIRA) and Wiiki system (Confluence). Also they sell a SVN variant (Stash) and more stuff. Unfortunately, Atlassian policies have turned operating JIRA/Confluence into a bottomless pit: Instead of integrating important functionality into JIRA, Atlassian focuses on making the UI incomprehensible ("new project navigation"). Functionality and workarounds for Atlassian bugs must be bought from third-party developers , which is hideously expensive due to annual licensing fees. Gantt chart? Go buy a plugin. Complex search queries? Go buy a plugin. For free, you get buggy UI changes which confuse users and make it impossible to select projects. While I do trust the web site, I would warn against using Atlassian products unless you are prepared to spend a LOT of money on plugins to get the functionality you want, and a LOT of time explaining Atlassian bugs to your users.