Alnuth : Algebraic number theory and an interface to PARI/GP ( https://www.gap-system.org/Packages/alnuth.html )
AutoDoc : Generate documentation from GAP source code ( https://www.gap-system.org/Packages/autodoc.html )
GAPDoc : A Meta Package for GAP Documentation ( https://www.gap-system.org/Packages/gapdoc.html )
HAPcryst : A HAP extension for crytallographic groups ( https://www.gap-system.org/Packages/hapcryst.html )
MapClass : A Package For Mapping Class Orbit Computation ( https://www.gap-system.org/Packages/mapclass.html )
SmallGrp : The GAP Small Groups Library ( https://www.gap-system.org/Packages/smallgrp.html )
aclib : Almost Crystallographic Groups - A Library and Algorithms ( https://www.gap-system.org/Packages/aclib.html )
atlasrep : A GAP Interface to the Atlas of Group Representations ( https://www.gap-system.org/Packages/atlasrep.html )
autpgrp : Computing the Automorphism Group of a p-Group ( https://www.gap-system.org/Packages/autpgrp.html )
cohomolo : Cohomology groups of finite groups on finite modules ( https://www.gap-system.org/Packages/cohomolo.html )
corelg : computation with real Lie groups ( https://www.gap-system.org/Packages/corelg.html )
crime : A GAP Package to Calculate Group Cohomology and Massey Products ( https://www.gap-system.org/Packages/crime.html )
crisp : Computing with Radicals, Injectors, Schunck classes and Projectors ( https://www.gap-system.org/Packages/crisp.html )
crypting : Hashes and Crypto in GAP ( https://www.gap-system.org/Packages/crypting.html )
cryst : Computing with crystallographic groups ( https://www.gap-system.org/Packages/cryst.html )
crystcat : The crystallographic groups catalog ( https://www.gap-system.org/Packages/crystcat.html )
ctbllib : The GAP Character Table Library ( https://www.gap-system.org/Packages/ctbllib.html )
datastructures : Collection of standard data structures for GAP ( https://gap-packages.github.io/datastructures/ )
design : The Design Package for GAP ( https://www.gap-system.org/Packages/design.html )
digraphs : Graphs, digraphs, and multidigraphs in GAP ( https://www.gap-system.org/Packages/digraphs.html )
factint : Advanced Methods for Factoring Integers ( https://www.gap-system.org/Packages/factint.html )
fga : Free Group Algorithms ( https://www.gap-system.org/Packages/fga.html )
gap-recommended : Meta package pulling the recommended pkgs for gap ( https://www.gap-system.org/ )
gbnp : computing Grobner bases of noncommutative polynomials ( https://gap-packages.github.io/gbnp/ )
genss : Generic Schreier-Sims ( https://www.gap-system.org/Packages/genss.html )
grape : GRaph Algorithms using PErmutation groups ( https://www.gap-system.org/Packages/grape.html )
guava : GAP package for computing with error-correcting codes ( https://www.gap-system.org/Packages/guava.html )
hap : Homological Algebra Programming ( https://www.gap-system.org/Packages/hap.html )
hecke : Calculating decomposition matrices of Hecke algebras ( https://www.gap-system.org/Packages/hecke.html )
images : Finding minimal and canonical images in permutation groups ( https://gap-packages.github.io/images/ )
io : Bindings for low level C library I/O routines ( https://gap-packages.github.io/io/ )
irredsol : Irreducible soluble linear groups over finite fields and more ( https://github.com/bh11/irredsol )
laguna : Lie AlGebras and UNits of group Algebras ( https://www.gap-system.org/Packages/laguna.html )
liealgdb : A database of Lie algebras ( https://www.gap-system.org/Packages/liealgdb.html )
liepring : Database and algorithms for Lie p-rings ( https://www.gap-system.org/Packages/liepring.html )
liering : finitely presented Lie rings ( https://www.gap-system.org/Packages/liering.html )
loops : Computing with quasigroups and loops in GAP ( https://www.gap-system.org/Packages/loops.html )
nq : Nilpotent Quotients of Finitely Presented Groups ( https://gap-packages.github.io/nq/ )
orb : Methods to enumerate orbits ( https://www.gap-system.org/Packages/orb.html )
p_group_cohomology_helper : GAP helper for p_group_cohomology SageMath package ( https://users.fmi.uni-jena.de/~king/index.html )
polenta : Polycyclic presentations for matrix groups ( https://www.gap-system.org/Packages/polenta.html )
polycyclic : Computation with polycyclic groups ( https://www.gap-system.org/Packages/polycyclic.html )
polymaking : Interfacing the geometry software polymake ( https://www.gap-system.org/Packages/polymaking.html )
primgrp : GAP Primitive Permutation Groups Library ( https://www.gap-system.org/Packages/primgrp.html )
quagroup : a package for doing computations with quantum groups ( https://www.gap-system.org/Packages/quagroup.html )
radiroot : Computing with Radicals, Injectors, Schunck classes and Projectors ( https://www.gap-system.org/Packages/radiroot.html )
resclasses : Set-Theoretic Computations with Residue Classes ( https://www.gap-system.org/Packages/resclasses.html )
semigroups : A package for semigroups and monoids ( https://www.gap-system.org/Packages/semigroups.html )
singular : gap interface to sci-mathematics/singular ( https://gap-packages.github.io/singular/ )
sla : a package for doing computations with simple Lie algebras ( https://www.gap-system.org/Packages/sla.html )
sonata : System of nearrings and their applications ( https://www.gap-system.org/Packages/sonata.html )
sophus : Computing in nilpotent Lie algebras ( https://www.gap-system.org/Packages/sophus.html )
tomlib : The GAP Library of Tables of Marks ( https://www.gap-system.org/Packages/tomlib.html )
toric : toric varieties and some combinatorial geometry computations ( https://www.gap-system.org/Packages/toric.html )
transgrp : GAP Transitive Groups Library ( https://www.gap-system.org/Packages/transgrp.html )
utils : Utility functions in GAP ( https://www.gap-system.org/Packages/utils.html )
Add an ebuild in portage :
The ebuild is now in the portage tree.
You can also use layman : emerge layman then layman -a sage-on-gentoo
For Paludis use this rsync : rsync://gentoo.zugaina.org/sage-on-gentoo-portage
If you have a problem : ycarus(-at-)zugaina.org