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Translations:Ebuild repository/78/en
From Gentoo Wiki (test)
Ebuild repositories are nothing more (or less) than a set of files (ebuilds, metadata files, ...). These can be pulled in from public repositories (git, CVS, SVN ...) or downloaded as tarballs and extracted manually onto the system. It is advised to use managed repositories by trusted third parties; any installed ebuild repository will cause Portage to look through the overlaid files when deciding which software to install. If compromised code is in the ebuild repository, then compromised packages could be installed on the system.