The beginning of Chebfun was a message sent on December 4, 2001 by Nick Trefethen to his Oxford DPhil student Zachary Battles, a Rhodes Scholar from Pennsylvania. Seven possible thesis topics were proposed, of which Battles chose this one:
A MATLAB EXTENSION FOR FUNCTIONS. One day I hope to find a student interested in Matlab software building and in spectral discretizations who might want to try to build an extension of Matlab in which a vector becomes a continuum, and a matrix becomes a continuum-by-discrete object. Then one would have QR decompositions, least-squares, etc., all based invisibly, perhaps, on global polynomial interpolants in Chebyshev points. For these you'd want to have read my "Spectral Methods in Matlab".
The rest, as they say, is history.
On December 4 here in 2021, 15 members of the Chebfun team gathered by Zoom to celebrate this landmark. The screenshot shows Grady Wright, Alex Townsend, Nick Trefethen, Anthony Austin, Silviu Filip, Behnam Hashemi, Toby Driscoll, Mark Richardson, Mohsin Javed, Kate McLoughlin, Nick Hale, and Rodrigo Platte. Also at the party but not shown were Ásgeir Birkisson, Yuji Nakatsukasa, and Ricardo Pachón.