in this blogpost i hope to explain my experience of contributing to nixpkgs until this moment

Note: i am not a native english speaker please let me know my mistakes and help me improve my english

Creating my first package (derivition)

i was working on my experimental accessibility program when working on accessibility abstraction of it i wanted to reflect over enums on c++ for looping over enums, doing map lookups, and for printing in program names of atspi enums for doing theses i wanted to use magic enum library for doing these but this wasn’t packaged in nixpkgs unlike my other dependencies so i went ahead and created a simple derivation(package) in my flake.nix

inputs = {
     magic-enum-repo = {
       url = "github:Neargye/magic_enum/v0.8.2";
       flake = false;
     };
}

firstly i added magic enum as a flake input and then

outputs =
...
let
pkgs = nixpkgs.legacyPackages.${system};
magic-enum = pkgs.stdenv.mkDerivation
  {
    pname = "magic-enum"; #1
    version = "0.8.2";

    src = magic-enum-repo; #2

    nativeBuildInputs = with pkgs; [ cmake ]; #3

    doCheck = true; #4
  };
in
...

i created a simple derivition:

1. wrote the name and version
2. added source from flake input
3. i added cmake build system as build time dependency
4. enabled tests to be sure library works properly

it was pretty easy to be fair magic enum is pretty trivial to package library it had cmake install scripts so nix automatically installed it to $out and it didn’t had any dependency except c++ compiler lastly it didn’t had any fetch_content() calls in cmake so no network sandbox complexity too

since it was easy to package i wanted to upstream it so i looked up how to contributing guide of nixpkgs and contributing section of nixpkgs manual then i forked and shallow cloned nixpkgs

• added myself as maintainer as maintainer and commited to my fork with commit message format required for changes

...
Alper-Celik = {
    email = "dev.alpercelik@gmail.com";
    name = "Alper Çelik";
    github = "Alper-Celik";
    githubId = 110625473;
    keys = [{
      fingerprint = "6B69 19DD CEE0 FAF3 5C9F  2984 FA90 C0AB 738A B873";
    }];
  };
...

• modified derivition to use fetchFromGitHub instead of simpler flake input

...
  src = fetchFromGitHub {
    owner = "Neargye";
    repo = "magic_enum";
    rev = "v${version}";
    sha256 = "sha256-...";
  };
...

• added meta data about package

...
meta = with lib;{
    description = "Static reflection for enums (to string, from string, iteration) for modern C++";
    homepage = "https://github.com/Neargye/magic_enum";
    license = licenses.mit;
    maintainers = with maintainers; [ Alper-Celik ];
  };
...

• lastly navigated (it at least had some organization) pkgs/top-level/all-packages.nix for finding correctish spot for package and i found it about at 22.000 th line

# about 22.000 lines
...
  magic-enum = callPackage ../development/libraries/magic-enum { };
...
# who knows how many lines at the bottom of file

and i was ready to create pr for it i created and waited about a week and @NickCao pointed out i forget to format package commit message and [recommended formatting package dependencies with nixpkgs-fmt. i was actually using nixpkgs-fmt with nul-ls.nvim, it was actually formatted but when i put one dependency to other line it expanded and this fixed formatting. to be fair i was put the formatted the pr message like that and forget to actually format commit message i fixed that.

after fixing problems with pr i thanked @NickCao for reviewing my pr with my perfect english.

after about a day later @NickCao merged my pr and i was officially a nixpkgs package maintainer

after a while i backported to 22.11 release because i was using stable release on my flake.nix and it got quickly merged by @superherointj too

after some more time i switched to using unstable release system wide instead of having stable and unstable nixos side by side this broked running Qt info gui when developing because Qt program wasn’t wrapped while developing so i updated my flake.nix to nixos-unstable too but then it started to build magic-enum instead of fetching from binary cache and failed i guess binary cache failed too and because of that nix tried to build it. after looking to logs it was about some wide characters (emojis) while building unit tests, after looking into issues tacker of magic-enum i saw it was a problem with building on gcc 12 and unstable releases updating to gcc 12 broked the package, i submitted a pr disabling building of the tests

# last shape of the pr:

# disable tests until upstream fixes build issues with gcc 12
# see https://github.com/Neargye/magic_enum/issues/235
doCheck = false;
cmakeFlags = [
  "-DMAGIC_ENUM_OPT_BUILD_TESTS=OFF"
];

after @wegank helped me with grammar, layout of the sentences and misspellings (he fixed them) he merged the pr. i will probably enable tests on next version of the library if building tests on the latest compilers gets fixed by then lastly there was no need to backport this pr since stable(22.11) was still using gcc 11