We want to continue growing the list of people who have a solid understanding of PatchTheory. Note that some of these people hang out in #darcs-theory on so do stop by for a chat!

How to use this directory

  • Note that patch theory questions are best asked on the mailing list (darcs-users 2008-08).
  • Perhaps browse this list to have a better idea who is answering your question, or who you are debating with
  • Put yourself on this list

    • … even if you are just passively learning patch theory.
    • … if you want to formalise patch theory in a certain way (perhaps you can find a kindred spirit to work with)
    • … if you have a wacky patch theory idea (perhaps somebody else will have a similar wacky idea and you can collaborate!)
  • It would help if you put down a short explanation of the extent of your understanding.
  • Note that “last seen” refers to the last time we heard from them about patch theory

Patch theorists

People who have actively been involved in the development of darcs patch theory.

  • David Roundy

    • David devised patch theory in the first place and probably understands the conflictors work in darcs 2 the best.
    • last seen: 2008-08
  • JasonDagit

    • Jason worked with David on the darcs 2 stuff. His master’s thesis is on darcs. We are all looking forward to seeing it!
    • gaps: …
    • last seen: 2009-10
  • Ian Lynagh

    • Ian has participated in many of the core patch theory discussions. He has also started the Camp project, to develop and prove correct a darcs-like theory that will hopefully form the basis for darcs 3.
    • last seen: 2008-09
  • GaneshSittampalam

    • Ganesh was working on conflictors up to 2005/2006. Along with Arjan, he figures as a character in the wikibook.
    • also worked on: GaneshPatchAlgebra
    • gaps: Ganesh said he doesn’t really understand what’s going on recently (say in darcs 2)
    • last seen: 2006
  • Arjan Boeijink

    • Arjan was working on conflictors up to 2005/2006, if I recall correctly. He has recently resurfaced. Welcome back!
    • last seen: 2008-09
  • Jean-Phillipe Bernardy

    • Jean-Phillipe_ and students were working on an alternative patch theory in which conflicts do not exist. Instead, an internal representation of repository state is chosen to accomodate conflicting states.
    • “A patch theory should be divided in two parts… an internal representation for data… [and] a relation between internal and external representation” (see FoCAL for details)
    • last seen: 2009-01
  • Judah Jacobson

    • Judah wrote up a formalisation of patch theory using inverse semigroups…
    • last seen: 2009-10

Alternative patch theorists

I don’t like making distinctions here, but I guess it is useful to have a list of people who have suggested reformulations of patch theory, or patch theory as it is not (currently) used by darcs

Patch theory students

  • Eric Kow

    • Eric (with Arjan’s guidance) wrote the introductory chapter on the understanding darcs wikibook, so he has a rudimentary understanding of patch theory without conflicts (i.e. he knows what commutation is and how darcs uses it).
    • gaps: He doesn’t have a clue what goes on after there, nor does he really get any of the new properties like permutivity
    • last seen: 2007
  • Petr Rockai

    • last seen: 2008-08
  • Apfelmus

    • Interested bystander who likes mathematical correctness and proofs.
    • last seen: 2009-10
  • Reinier Lamers

    • Thinks he should understand patch theory as a darcs coder
    • last seen: 2009-04