Improve folder structure

nix/main/packages.nix

@@ -0,0 +1,168 @@
+{ config, lib, pkgs, unstable, ... }:
+
+{
+  # System-wide packages to install.
+  environment.systemPackages = with unstable;
+    let
+      common = [
+        # utils
+        bat
+        bind
+        binutils-unwrapped
+        colordiff
+        curl
+        direnv
+        exa
+        fd
+        fzf
+        git
+        gnumake
+        jq
+        ripgrep
+        tree
+        unzip
+        zip
+
+        # education
+        anki
+
+        # monitoring
+        htop
+
+        # password
+        gopass
+
+        # social media
+        rtv
+
+        # imaging
+        gifsicle
+        gimp
+
+        # editors
+        libreoffice
+        vscodium
+
+        # audio
+        audio-recorder
+        spotify
+
+        # video
+        youtube-dl
+        vlc
+
+        # network
+        bandwhich
+        deluge
+        nmap
+        openvpn
+        postman
+
+        # terraform
+        terraform-ls
+        terraform_0_14
+        tflint
+        tfsec
+
+        # gcp
+        google-cloud-sdk
+
+        # jvm
+        jdk8
+        gradle
+        groovy
+        maven
+
+        # encryption
+        cryptsetup
+
+        # browser
+        brave
+        firefox
+
+        # docker
+        docker
+        docker-compose
+
+        # k8s
+        kubectl
+        kubernetes-helm
+
+        # nix
+        nix-index
+        nixfmt
+        nixpkgs-fmt
+        nixpkgs-review
+        rnix-lsp
+
+        # games
+        steam
+        minecraft
+        yuzu
+
+        # communication
+        discord
+        element-desktop
+        signal-desktop
+        slack
+        zoom-us
+
+        ## aws
+        awscli2
+        ssm-session-manager-plugin
+
+        # python
+        black
+        python38
+        python38Packages.ipython
+        python38Packages.pip
+        python38Packages.poetry
+        python38Packages.setuptools
+        python38Packages.virtualenv
+
+        # fonts
+        dejavu_fonts
+        fira-code
+        fira-code-symbols
+        fira-mono
+        font-awesome
+        google-fonts
+        noto-fonts
+        noto-fonts-cjk
+        noto-fonts-emoji
+        noto-fonts-extra
+
+        # misc
+        asciinema
+        github-cli
+        glibcLocales
+        go-jira
+        hadolint
+        nodejs-12_x
+        imagemagick
+        pfetch
+        pinentry-curses
+        shellcheck
+        shfmt
+        starship
+        xclip
+        xdg_utils
+        zathura
+
+        # overlays
+        # lpass
+        # rfd
+        # vpngate
+
+      ];
+    in common;
+
+  # Don't install optional default packages.
+  environment.defaultPackages = [ ];
+
+  # Install ADB and fastboot.
+  programs.adb.enable = true;
+
+  # Install GnuPG agent.
+  programs.gnupg.agent.enable = true;
+}