The code is developed by the Castep Developers Group (CDG) who are all UK based academics. Current CDG members are:
- Matthew Segall - Main author of the code specification, and responsible for all the low-level communications and basis set coding. Also the population analysis algorithms.
- Matt Probert - Responsible for the geometry optimisation and molecular dynamics coding (including path-integral molecular dynamics), and keeper of the parameters and algor modules.
- Stewart Clark - Responsible for the band structure and exchange-correlation functional coding and keeper of the cell and FFT modules. Also co-author of the linear response code.
- Chris Pickard - Responsible all pseudopotential coding, amongst other things. Also co-author of the NMR code.
- Phil Hasnip - Responsible for the electronic energy minimisation coding (including density mixing and ensemble DFT), OpenMP threading, band-parallelism, run-time profiling and parallel efficiency report, and wavefunction subroutines. Also works on optimisation and parallel performance.
- Keith Refson - Responsible for phonon and E-field calculations and co-author of the linear response code.
- Jonathan Yates- Co-author of the NMR code, responsible for spectral module (dos, optics, eels), and architect of the spin-orbit functionality.
- Albert Bartok-Partay - Main author of the meta-GGA code, and contributor to many aspects of CASTEP.
- Mike Payne - CASTEP creator and general overseer of the whole project.
Over the years many other people have contributed code to CASTEP including:
- Peter Haynes - wrote much of the initial density mixing code
- Jim White - many contributions to initial density mixing and electronic minimisation code
- Victor Milman - much bug spotting and fixing throughout code
- Niri Govind - transition state search code
- Michael Gibson - non-local exchange-correlation functionals code
- Paul Tulip - contributions to linear response code
- Vincent Cocula - anti-ferromagnetic initial state code
- Barbara Montanari - contributions to finite displacement phonons code
- David Quigley - contributions to molecular dynamics code
- Maff Glover - path integral molecular dynamics code
- Leo Bernasconi - maximally-localised Wannier function code
- Shang-Peng Gao - core-level spectra code
- Erik McNellis - DFT-D (semi-empirical dispersion correction) code
- Joerg Meyer - contributions to DFT+D code plus castep2cube tool
- Alexander Perlov - contributions to LDA+U code
- Dominik Jochym - Responsible for the TDDFT code, HPC optimization of checkpoint/read code, DFPT-Raman and NLO.
- Martin Plummer - multiprocessor optimizations of parallel FFT
- Chris Armstrong - shared-memory optimizations of parallel FFT
- Julian Gale - code for PBEsol XC functional
- Joly Aarons - code for low-memory BFGS (L-BFGS) algorithm
- Brent Walker - contributions to path-integral MD (PIMD) code
- Daniel Jones - non-collinear magnetism and spin-orbit coupling
- Ian Bush - shared-memory interface and software infrastructure, prototype parallel iterative matrix diagonaliser
- Ed Higgins - OpenMP threading and parallel iterative matrix diagonaliser
- Andrew Morris - Posix compliant command-line argument handling
- Tim Green - J-coupling with Ultrasoft Pseudopotentials
- Bi-Ching Shi - EPR g-tensor
- Chris Armstrong - Shared memory optimisation
- Jacob Wilkins - Pair potential and Hugoniostat
- Peter Byrne - 2n+1 Raman, Dispersion corrections, electron-phonon coupling, spin constraints, castep python
- James Womack - DLMG interface (implicit solvent)
- Jacek Dziedzic - DLMG interface (implicit solvent)
- Luc LeBlanc - XDM
- Tamas Stenczel - GAP interface
- James Kermode - Castep python, geometry optimisation precondictioner
- Simone Sturniolo - NEB
- Benjamin Shi - X-ray structure factors
- Ben Durham - LibXC interface, spin-polarised DFPT, solvation forces
- Matthew Evans - ACE
- Rachel Strong - EPR g-tensor
- Sian Joyce - NMR J-coupling
- Matthew Smith - ACE
- Zachery Hawkhead - Source-free XC functionals
- Visagan Ravindran - Local Fock Exchange (LFX)
- Tom Hollands - Optimised Effective Potential (OEP)
- Arjen Tamerus - OpenMP threading
Many of the original library pseudopotential files and on-the-fly pseudopotential definitions were contributed by Ming-Hsien Lee.