Change:
The mathics test does not work because: /cc (commit history)
I see the same error with on the 20.03 beta channel. I think it also happens on Master. It used to work (maybe a few weeks ago? if I have time I'll bisect).
I removing mathics.

Discussion:
bepasty = 215; # pumpio = 216; # unused, removed 2018-02-24 nm-openvpn = 217; <del> mathics = 218; </del> <ins> # mathics = 218; # unused, removed 2020-08-15 </ins> ejabberd = 219; postsrsd = 220; opendkim = 221;

./services/misc/leaps.nix ./services/misc/lidarr.nix ./services/misc/mame.nix <del> ./services/misc/mathics.nix </del> ./services/misc/matrix-appservice-discord.nix ./services/misc/matrix-synapse.nix ./services/misc/mautrix-telegram.nix

(mkRemovedOptionModule [ "services" "osquery" ] "The osquery module has been removed") (mkRemovedOptionModule [ "services" "fourStore" ] "The fourStore module has been removed") (mkRemovedOptionModule [ "services" "fourStoreEndpoint" ] "The fourStoreEndpoint module has been removed") <ins> (mkRemovedOptionModule [ "services" "mathics" ] "The Mathics module has been removed") </ins> (mkRemovedOptionModule [ "programs" "way-cooler" ] ("way-cooler is abandoned by its author: " + "https://way-cooler.org/blog/2020/01/09/way-cooler-post-mortem.html")) (mkRemovedOptionModule [ "services" "xserver" "multitouch" ] ''

<del> { pkgs, lib, config, ... }: with lib; let cfg = config.services.mathics; in { options = { services.mathics = { enable = mkEnableOption "Mathics notebook service"; external = mkOption { type = types.bool; default = false; description = "Listen on all interfaces, rather than just localhost?"; }; port = mkOption { type = types.int; default = 8000; description = "TCP port to listen on."; }; }; }; config = mkIf cfg.enable { users.users.mathics = { group = config.users.groups.mathics.name; description = "Mathics user"; home = "/var/lib/mathics"; createHome = true; uid = config.ids.uids.mathics; }; users.groups.mathics.gid = config.ids.gids.mathics; systemd.services.mathics = { description = "Mathics notebook server"; wantedBy = [ "multi-user.target" ]; after = [ "network.target" ]; serviceConfig = { User = config.users.users.mathics.name; Group = config.users.groups.mathics.name; ExecStart = concatStringsSep " " [ "${pkgs.mathics}/bin/mathicsserver" "--port" (toString cfg.port) (if cfg.external then "--external" else "") ]; }; }; }; } </del>

mailcatcher = handleTest ./mailcatcher.nix {}; mariadb-galera-mariabackup = handleTest ./mysql/mariadb-galera-mariabackup.nix {}; mariadb-galera-rsync = handleTest ./mysql/mariadb-galera-rsync.nix {}; <del> mathics = handleTest ./mathics.nix {}; </del> matomo = handleTest ./matomo.nix {}; matrix-synapse = handleTest ./matrix-synapse.nix {}; mediawiki = handleTest ./mediawiki.nix {};

<del> import ./make-test.nix ({ pkgs, ... }: { name = "mathics"; meta = with pkgs.stdenv.lib.maintainers; { maintainers = [ benley ]; }; nodes = { machine = { ... }: { services.mathics.enable = true; services.mathics.port = 8888; }; }; testScript = '' startAll; $machine->waitForUnit("mathics.service"); $machine->waitForOpenPort(8888); $machine->succeed("curl http://localhost:8888/"); ''; }) </del>

<del> { stdenv , buildPythonPackage , fetchFromGitHub , django , python , cython , sympy , ply , mpmath , dateutil , colorama , six , pexpect }: if (stdenv.lib.versionOlder django.version "1.8") || (stdenv.lib.versionAtLeast django.version "1.9") then throw "mathics only supports django-1.8.x" else buildPythonPackage rec { pname = "mathics"; version = "0.9"; src = fetchFromGitHub { owner = "mathics"; repo = "Mathics"; rev = "v${version}"; sha256 = "0xzz7j8xskj5y6as178mjmm0i2xbhd4q4mwmdnvghpd2aqq3qx1c"; }; buildInputs = [ pexpect ]; prePatch = '' substituteInPlace setup.py --replace "sympy==0.7.6" "sympy" ''; postFixup = '' wrapPythonProgramsIn $out/bin $out patchPythonScript $out/${python.sitePackages}/mathics/manage.py ''; propagatedBuildInputs = [ cython sympy django ply mpmath dateutil colorama six ]; meta = with stdenv.lib; { description = "A general-purpose computer algebra system"; homepage = "http://www.mathics.org"; license = licenses.gpl3; maintainers = [ maintainers.benley ]; }; } </del>

manpages = man-pages; # added 2015-12-06 mariadb-client = hiPrio mariadb.client; #added 2019.07.28 matcha = throw "matcha was renamed to matcha-gtk-theme"; # added 2020-05-09 <ins> mathics = throw "mathics has been removed from nixpkgs, as it's unmaintained"; # added 2020-08-15 </ins> matrique = spectral; # added 2020-01-27 mbedtls_1_3 = throw "mbedtls_1_3 is end of life, see https://tls.mbed.org/kb/how-to/upgrade-2.0"; # added 2019-12-08 mess = mame; # added 2019-10-30

marlin-calc = callPackage ../tools/misc/marlin-calc {}; <del> mathics = with python2Packages; toPythonApplication mathics; </del> masscan = callPackage ../tools/security/masscan { stdenv = gccStdenv; };

markdown-macros = callPackage ../development/python-modules/markdown-macros { }; <del> mathics = callPackage ../development/python-modules/mathics { }; </del> matplotlib = let path = if isPy3k then ../development/python-modules/matplotlib/default.nix else ../development/python-modules/matplotlib/2.nix;