The following list gives the authors (indicated by A) who designed the code in the first place, as well as the current maintainers (indicated by M) of the various modules of which &GAP; is composed.

Since the process of modularization was started only recently, there might be omissions both in scope and in contributors. The compilers of the manual apologize for any such errors and promise to rectify them in future editions.

Kernel
Frank Celler (A), Steve Linton (AM), Frank Lübeck (AM), Werner Nickel (AM), Martin Schönert (A)
Automorphism groups of finite pc groups
Bettina Eick (A), Werner Nickel (M)
Binary Relations
Robert Morse (AM), Andrew Solomon (A)
Characters and Character Degrees of certain solvable groups
Hans Ulrich Besche (A), Thomas Breuer (AM)
Classes in nonsolvable groups
Alexander Hulpke (AM)
Classical Groups
Thomas Breuer (AM), Frank Celler (A), Stefan Kohl (AM), Frank Lübeck (AM), Heiko Theißen (A)
Congruences of magmas, semigroups and monoids
Robert Morse (AM), Andrew Solomon (A)
Cosets and Double Cosets
Alexander Hulpke (AM)
Cyclotomics
Thomas Breuer (AM)
Dixon-Schneider Algorithm
Alexander Hulpke (AM)
Documentation Utilities
Frank Celler (A), Heiko Theißen (A), Alexander Hulpke (A), Willem de Graaf (A), Steve Linton (A), Werner Nickel (A), Greg Gamble (AM)
Factor groups
Alexander Hulpke (AM)
Finitely presented groups
Volkmar Felsch (A), Alexander Hulpke (AM), Martin Schönert (A)
Finitely presented monoids and semigroups
Isabel Araújo (A), Derek Holt (A), Alexander Hulpke (A), James Mitchell (M), Götz Pfeiffer (A), Andrew Solomon (A)
&GAP; for MacOS

Burkhard Höfling (AM)
Group actions
Heiko Theißen (A) and Alexander Hulpke (AM)
Homomorphism search
Alexander Hulpke (AM)
Homomorphisms for finitely presented groups
Alexander Hulpke (AM)
Identification of Galois groups
Alexander Hulpke (AM)
Intersection of subgroups of finite pc groups
Frank Celler (A), Bettina Eick (A), Werner Nickel (M)
Irreducible Modules over finite fields for finite pc groups
Bettina Eick (AM)
Isomorphism testing with random methods
Hans Ulrich Besche (AM), Bettina Eick (AM)
Lie algebras
Thomas Breuer (A), Craig Struble (A), Juergen Wisliceny (A), Willem A. de Graaf (AM)
Monomiality Questions
Thomas Breuer (AM), Erzsébet Horváth (A)
Multiplier and Schur cover
Werner Nickel (AM), Alexander Hulpke (AM)
One-Cohomology and Complements
Frank Celler (A) and Alexander Hulpke (AM)
Partition Backtrack algorithm
Heiko Theißen (A), Alexander Hulpke (M)
Permutation group composition series
Ákos Seress (AM)
Permutation group homomorphisms
Ákos Seress (AM), Heiko Theißen (A), Alexander Hulpke (M)
Permutation Group Pcgs
Heiko Theißen (A), Alexander Hulpke (M)
Possible Permutation Characters
Thomas Breuer (AM), Götz Pfeiffer (A)
Possible Class Fusions, Possible Power Maps
Thomas Breuer (AM)
Primitive groups library
Heiko Theißen (A), Colva Roney-Dougal (AM)
Properties and attributes of finite pc groups
Frank Celler (A), Bettina Eick (A), Werner Nickel (M)
Random Schreier-Sims
Ákos Seress (AM)
Rational Functions
Frank Celler (A) and Alexander Hulpke (AM)
Semigroup relations
Isabel Araújo (A), Robert F. Morse (AM), Andrew Solomon (A)
Special Pcgs for finite pc groups
Bettina Eick (AM)
Stabilizer Chains
Ákos Seress (AM), Heiko Theißen (A), Alexander Hulpke (M)
Strings and Characters

Martin Schönert (A), Frank Celler (A), Thomas Breuer (A), Frank Lübeck (AM)
Structure Descriptions for Finite Groups
Stefan Kohl (AM), Markus Püschel (A), Sebastian Egner (A)
Subgroup lattice
Martin Schönert (A), Alexander Hulpke (AM)
Subgroup lattice for solvable groups
Alexander Hulpke (AM)
Subgroup presentations
Volkmar Felsch (A), Werner Nickel (M)
The Help System
Frank Celler (A), Frank Lübeck (AM)
Tietze transformations
Volkmar Felsch (A), Werner Nickel (M)
Transformation semigroups
Isabel Araújo (A), Robert Arthur (A), Robert F. Morse (AM), Andrew Solomon (A)
Transitive groups library
Alexander Hulpke (AM)
Two-cohomology and extensions of finite pc groups
Bettina Eick (AM)