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Gentoo Prefix
Description To bring out the virtues of Gentoo on different operating systems, the Gentoo Prefix project develops and maintains a way of installing Gentoo systems in a non-standard location, designated by a "prefix".
Project email
Packages p.g.o/
Code repository
Mailing list (archive)
IRC channel #gentoo-prefix (webchat)
Bugs Related bugs
Last elected: 2019-05-04
(and inherited member(s))
Parent Project Gentoo
Project listing

To bring out the virtues of Gentoo Linux on different operating systems, the Gentoo Prefix project develops and maintains a way of installing Gentoo systems in a non-standard location, designated by a "prefix".

Usually, Gentoo Linux's package manager (Portage) installs in the root of the filesystem hierarchy known as /. On systems other than Gentoo Linux, this usually results in problems, due to conflicts of software packages, unless the OS is adapted like Gentoo FreeBSD. Instead, Gentoo Prefix installs within an offset, known as a prefix, allowing users to install Gentoo in another location in the filesystem hierarchy, hence avoiding conflicts. Next to this offset, Gentoo Prefix runs unprivileged, meaning no root user or rights are required to use it.

By using an offset (the "prefix" location), it is possible for many "alternative" user groups to benefit from a large part of the packages in the Gentoo ebuild repository. Currently users of the following systems successfully run Gentoo Prefix: macOS on PowerPC and Intel, Linux on x86, x86_64 and arm, Solaris 11 on Sparc, Sparc/64, x86 and x86_64. Other platforms have been successfully used in the past.

Today, there up to 3 variants of Prefix:

1. RAP as in "RAP ain't Prefix" (USE="prefix")
For Android and Linux, using host kernel but it's own glibc. This is most similar to Gentoo Linux and does neither need the prefix-overlay nor baselayout-prefix once bootstrapped.

2. Prefix Guest (USE="prefix prefix-guest")
The original Prefix as invented, using (POSIX) host libc+kernel. This is the only option for non-Linux, such as macOS (Darwin) and Solaris (SunOS) hosts.

3. Prefix Stack (USE="prefix prefix-guest prefix-stack") [unmaintained/unsupported]
Use build environment (bash, python, portage, compiler, etc) from some base Prefix (traditionally Prefix Guest on Cygwin) to build packages for platforms (traditionally Win32 using MSVC toolchain) that would not allow for a native portage – but without the whole cross-compilation pain, because Cygwin can very well execute native Win32 binaries.

Getting started


To get a prefixed Portage installed on your system, you need to go through a few steps we call bootstrapping. Note that, for systems where bash is missing, you need to bootstrap it first with the script.

Helper scripts

To ease the setup of a prefixed Portage installation, the Gentoo Prefix project provides a script called This script is a sort of kickstart in the bootstrap process, automating downloading the Portage tree, installing Portage and the necessary temporary helper applications. In addition, it tries to setup a profile and prepares those settings that it can deduce automatically.

Bootstrap guides

The following guides give a detailed description on how to install a Gentoo Prefix system:

Developer platforms

Platform-specific notes

  • Project:Android
  • Prefix/Darwin — brings the power of Gentoo to Darwin (macOS/OS X) based systems, similar to pkgsrc, macports, and homebrew.

Platform matrix

To keep track of the supported platforms, the following matrix is maintained. It also provides feedback on which developer is maintaining the platform or has direct access to such systems.

Fabian Groffen (grobian) Benda Xu (heroxbd) Guilherme Amadio (amadio)
amd64-linux x (non-RAP) x x
x86-linux o o
arm-linux x o
arm64-linux x o
arm64-macos x
ppc-macos o
x64-macos x x
x64-solaris x


Symbol Meaning
x actively maintained by developer
o accessible to developer
v outdated
a actively maintained by a user/contributor
e experimental effort by user/contributor

Tested Prefix Installations

A community-maintained table is available here. Results for partly automated bootstraps on a number of platforms are available here.


Resources offered by the prefix project include:

Hall of Fame

Over time, developers come and go again. Some mysteriously disappear, others loose interest and decide to leave. For all past contributors we would like to express our gratitude towards them for helping the Prefix project to become what it is today.

Past Prefix developers Contributions
ferringb Initial Portage developer to start the Prefix branch.
kito First prototypes of Prefix using a tree, Mac OS X installer, many first time engineering and development tasks.
exg Prefix Portage maintainer.
genstef Import of gtk+, qt4 and X11 applications for Mac OS X.
pipping Many package additions for Perl, Python, Ruby and Java, lots of Mac OS X targeted fixes and features, pioneer for Darwin9 (Leopard 10.5) support.
drizzt Mostly reviving Solaris 9 support, by fixing packages in the tree.
Christian Faulhammer (fauli) Gave FreeBSD 8 support a boost, some Interix testing.
Markus Duft (mduft) Gentoo Prefix on Interix and Windows.
Jeremy Olexa (darkside) Lots of support for various arches, merges to gx86, user support.
redlizard Initiated Prefix/libc, early works of the RAP (RAP Aint Prefix) project.
Michael Haubenwallner (haubi) Initiator of Prefix Portage, long standing guardian of AIX, HPUX and Solaris platforms

This page is based on a document formerly found on our main website
The following people contributed to the original document: Fabian Groffen (grobian)
They are listed here because wiki history does not allow for any external attribution. If you edit the wiki article, please do not add yourself here; your contributions are recorded on each article's associated history page.