At its most basic, Source Link generates a JSON file that maps raw source code locations to the source files in the build. This is most commonly an HTTPS URL to a file on GitHub, GitLab, Azure Repos, or Bitbucket. The JSON file gets embedded in the debug symbols, which the debugger uses to download the file on-demand. For non-public repos, this does not automatically grant anyone access to the source; the debugger would need to authenticate so existing permissions are maintained.