Weechat

WeeChat is an extensible chat client with a command line interface.

Plugins

WeeChat can be extended with plugins, which can be written in a variety of scripting languages. As these plugins may depend on external libraries, we need to take care that those are found by WeeChat. For example the Jabber plugin depends on the xmpppy python library, which is provided in a separate nix package. To make WeeChat find the library, we can override the weechat nix package and add the dependency as an extra build input, e.g. by changing the ~/.nixpkgs/config.nix as follows:

{
  packageOverrides = pkgs: rec {
    weechat = pkgs.weechat.override { extraBuildInputs = [ pkgs.xmpppy ]; };
  };
}

Making the wechat-otr.py plugin work

As of 2018-07-14, a workaround is needed. You have to override potr to use an old, vulnerable version of pycrypto (upstream progress in fixing this issue can be found at https://github.com/python-otr/pure-python-otr/issues/68):

      (weechat.override {
        configure = { availablePlugins, ... }: {
          plugins = [
            (availablePlugins.python.withPackages (ps: [
              (ps.potr.overridePythonAttrs (oldAttrs:
                {
                  propagatedBuildInputs = [
                    (ps.buildPythonPackage rec {
                      name = "pycrypto-${version}";
                      version = "2.6.1";

                      src = pkgs.fetchurl {
                        url = "mirror://pypi/p/pycrypto/${name}.tar.gz";
                        sha256 = "0g0ayql5b9mkjam8hym6zyg6bv77lbh66rv1fyvgqb17kfc1xkpj";
                      };

                      patches = pkgs.stdenv.lib.singleton (pkgs.fetchpatch {
                        name = "CVE-2013-7459.patch";
                        url = "https://anonscm.debian.org/cgit/collab-maint/python-crypto.git"
                          + "/plain/debian/patches/CVE-2013-7459.patch?h=debian/2.6.1-7";
                        sha256 = "01r7aghnchc1bpxgdv58qyi2085gh34bxini973xhy3ks7fq3ir9";
                      });

                      buildInputs = [ pkgs.gmp ];

                      preConfigure = ''
                        sed -i 's,/usr/include,/no-such-dir,' configure
                        sed -i "s!,'/usr/include/'!!" setup.py
                      '';
                    })
                  ];
                }
              ))
            ]))
          ];
        };
      })

An Example ~/.config/nixpkgs/overlays/weechat.nix, if you prefer single file overlays.

self: super:

{
  weechat = super.weechat.override {
    configure = { availablePlugins, ... }: {
      plugins = [
        (availablePlugins.python.withPackages (ps: [
          (ps.potr.overridePythonAttrs (oldAttrs:
            {
              propagatedBuildInputs = [
                (ps.buildPythonPackage rec {
                  name = "pycrypto-${version}";
                  version = "2.6.1";

                  src = super.fetchurl {
                    url = "mirror://pypi/p/pycrypto/${name}.tar.gz";
                    sha256 = "0g0ayql5b9mkjam8hym6zyg6bv77lbh66rv1fyvgqb17kfc1xkpj";
                  };

                  patches = super.stdenv.lib.singleton (super.fetchpatch {
                    name = "CVE-2013-7459.patch";
                    url = "https://anonscm.debian.org/cgit/collab-maint/python-crypto.git"
                      + "/plain/debian/patches/CVE-2013-7459.patch?h=debian/2.6.1-7";
                    sha256 = "01r7aghnchc1bpxgdv58qyi2085gh34bxini973xhy3ks7fq3ir9";
                  });

                  buildInputs = [ super.gmp ];

                  preConfigure = ''
                    sed -i 's,/usr/include,/no-such-dir,' configure
                    sed -i "s!,'/usr/include/'!!" setup.py
                  '';
                })
              ];
            }
          ))
        ]))
      ] ++ (with availablePlugins; [ perl tcl ruby guile lua ]);
    };
  };
}