termux: create channels/nixpkgs under real symlink target (dangling symlink blocks mkdir -p)

configurations/default.nix

@@ -9,4 +9,10 @@
     sapphira = import ./server.nix flakeContext; # sapphira
     wsl = import ./wsl.nix flakeContext; # wsl
   };
+  nixOnDroidConfigurations = {
+    epral = import ./mobile.nix flakeContext; # epral (Android via nix-on-droid)
+    # Alias so a plain `nix-on-droid switch` from a local clone
+    # (~/.config/nix-on-droid) picks up the device config without `#epral`.
+    default = import ./mobile.nix flakeContext;
+  };
 }

configurations/mobile.nix

@@ -18,7 +18,7 @@ let
     }:
     {
       imports = [
-        inputs.self.nixosModules.default # base defaultModule (termux-trimmed)
+        inputs.self.nixosModules.strict
       ];
 
       xlib.device = {
@@ -31,6 +31,11 @@ let
       # (default is bashInteractive)
       user.shell = "${pkgs.zsh}/bin/zsh";
 
+      # SSH user (matches `User oqyude` in the client's ~/.ssh/config).
+      # Default is "nix-on-droid"; home stays at the read-only
+      # /data/data/com.termux.nix/files/home either way.
+      user.userName = "oqyude";
+
       # Minimal termux settings (nix-on-droid options only:
       # environment.*, nix.*, time.*, user.*, system.*, android-integration.*)
 
@@ -44,25 +49,26 @@ let
         nano
 
         # Some common stuff that people expect to have
-        openssh
-        treefmt
-        git
-        procps
-        psmisc # provides killall (attr `killall` was removed from nixpkgs)
+        bzip2
         diffutils
         findutils
-        util-linux # renamed from utillinux
-        tzdata
-        hostname
-        man
+        git
         gnugrep
         gnupg
         gnused
         gnutar
-        bzip2
         gzip
-        zip
+        hostname
+        man
+        ncurses
+        openssh
+        procps
+        psmisc # provides killall (attr `killall` was removed from nixpkgs)
+        treefmt
+        tzdata
         unzip
+        util-linux # renamed from utillinux
+        zip
       ];
 
       # Backup etc files instead of failing to activate generation if a file already exists in /etc
@@ -71,12 +77,17 @@ let
       # Shared userspace home-manager config (same cozy shell as on NixOS hosts).
       # nix-on-droid forces home.username / home.homeDirectory from user.*,
       # so the strict module must not set them.
+      # xlib is injected via home-manager.extraSpecialArgs (the HM submodule
+      # does not inherit the nix-on-droid module args).
       home-manager = {
         useGlobalPkgs = true;
         backupFileExtension = "hm-bak";
+        extraSpecialArgs = {
+          inherit xlib;
+        };
         config = { ... }: {
           imports = [
-            ../home/shared/strict.nix
+            ../home/termux.nix
           ];
           home.stateVersion = "24.05";
         };

droid/default.nix

@@ -1,9 +0,0 @@
-{ inputs, ... }@flakeContext:
-{
-  nixOnDroidConfigurations = {
-    epral = import ./epral.nix flakeContext; # epral (Android via nix-on-droid)
-    # Alias so a plain `nix-on-droid switch` from a local clone
-    # (~/.config/nix-on-droid) picks up the device config without `#epral`.
-    default = import ./epral.nix flakeContext;
-  };
-}

flake.nix

@@ -120,7 +120,6 @@
     }
     // (import ./configurations flakeContext)
     // (import ./deploy flakeContext)
-    // (import ./droid flakeContext)
     // (import ./home flakeContext)
     // (import ./modules flakeContext)
     // (import ./overlays flakeContext)

home/termux.nix

@@ -2,6 +2,7 @@
   config,
   lib,
   pkgs,
+  xlib,
   ...
 }:
 # Shared "strict" home-manager module.
@@ -17,46 +18,52 @@
 # (which stay NixOS-only for now). When this module is wired into NixOS hosts
 # via sharedModules, deduplicate those files.
 {
-  home.packages = with pkgs; [
-    # Lazy (alias lc)
-    lazycli
+  home = {
+    packages = with pkgs; [
+      # Lazy (alias lc)
+      lazycli
 
-    # IDE
-    fresh-editor # EDITOR
+      # IDE
+      fresh-editor # EDITOR
 
-    # Base utils
-    curl
-    wget
-    fd
-    tree
-    dust
-    gdu
-    mc
-    rsync
-    jq
-    unzip
-    zip
-    zstd
+      # Base utils
+      curl
+      wget
+      fd
+      tree
+      dust
+      gdu
+      mc
+      rsync
+      jq
+      unzip
+      zip
+      zstd
 
-    # Net diagnostic
-    mtr
-    dnsutils
+      # Net diagnostic
+      mtr
+      dnsutils
 
-    # Monitoring
-    htop
-  ];
-
-  home.sessionVariables = {
-    TUCKR_HOME = "$HOME/Storage/dotfiles";
-    EDITOR = "fresh";
+      # Monitoring
+      htop
+    ];
+    sessionVariables = {
+      TUCKR_HOME = "$HOME/Storage/dotfiles";
+      EDITOR = "fresh";
+    };
+    file = {
+      ".nanorc".text = ''
+        set nowrap
+        set tabstospaces
+        set tabsize 2
+      '';
+      # Authorized keys for sshd (see modules/termux/default.nix).
+      # Declarative for now — the Store/.ssh symlink scheme is postponed.
+      ".ssh/authorized_keys".text = ''
+        ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIKduJia+unaQQdN6X5syaHvnpIutO+yZwvfiCP4qKQ/P
+      '';
+    };
   };
-
-  home.file.".nanorc".text = ''
-    set nowrap
-    set tabstospaces
-    set tabsize 2
-  '';
-
   programs = {
     # ---- Shell: zsh ----
     zsh = {
@@ -68,7 +75,12 @@
         enable = true;
         theme = "robbyrussell";
       };
-      loginExtra = "clear && fastfetch";
+      loginExtra = "clear && fastfetch && cd ~/.config/nix-on-droid";
+      # .zshenv — sourced by zsh in ALL sessions incl. non-login ssh commands.
+      # runit from nixpkgs defaults to /var/service as SVDIR, but our tree
+      # lives at ~/service (symlinked as /etc/service). Export it so that
+      # `sv status sshd` works without qualifying the path.
+      envExtra = "export SVDIR=/etc/service";
       initContent = ''
         beet-p() {
           local base="${config.home.homeDirectory}/.config/beets/My"
@@ -90,6 +102,7 @@
         lg = "lazygit";
         lc = "lazycli";
         gp = "git pull";
+        ns = "nix-on-droid switch --flake ~/.config/nix-on-droid#${xlib.device.hostname}";
         gp-ns = "gp && ns";
         gc = "git add . && git commit -m 'dev: автокоммит $(date +'%Y-%m-%d %H:%M:%S')'";
         y = "yazi";
@@ -97,6 +110,8 @@
         beet-path-library = "realpath --relative-to='${config.home.homeDirectory}/.config/beets/My' .";
         z-proxy = "export ALL_PROXY=socks5://localhost:10808";
         zh-proxy = "export HTTPS_PROXY=http://localhost:10808 && export HTTP_PROXY=http://localhost:10808";
+        nix-dir = "cd ~/.config/nix-on-droid";
+        q-ssh = "sv-start"; # start all supervised services (sshd, ...); manage with `sv status sshd` etc
 
         # beets
         beet-ima = "beet im ./ -A";

modules/default.nix

@@ -12,29 +12,22 @@ let
       # NixOS-only modules. termux runs nix-on-droid (its own module system,
       # class = "nixOnDroid"): options like services.*, users.*, sops.*, disko.*
       # and nixpkgs.overlays (flake assertion) do not exist there.
-      imports =
-        with inputs;
-        [
-          ./options.nix
-          (./. + "/${deviceType}") # specific modules
-        ]
-        ++ lib.optionals (deviceType != "termux") [
-          ./essentials
-          ./users.nix
+      imports = with inputs; [
+        ./essentials
+        ./options.nix
+        ./users.nix
+        (./. + "/${deviceType}")
 
-          home-manager.nixosModules.home-manager # home-manager module
-          # nix-index-database.nixosModules.nix-index # nix-index module
-          grub2-themes.nixosModules.default # grub2 themes module
-          sops-nix.nixosModules.sops # sops module
-          self.homeConfigurations.default.nixosModule # default homeConfigurations
-          disko.nixosModules.disko # disko module
-        ];
-      # nix-on-droid asserts that nixpkgs.* stays unset in flake mode.
-      nixpkgs.overlays = lib.mkIf (deviceType != "termux") (
-        with inputs; [
-          self.nixosOverlays.default
-        ]
-      );
+        home-manager.nixosModules.home-manager # home-manager module
+        # nix-index-database.nixosModules.nix-index # nix-index module
+        grub2-themes.nixosModules.default # grub2 themes module
+        sops-nix.nixosModules.sops # sops module
+        self.homeConfigurations.default.nixosModule # default homeConfigurations
+        disko.nixosModules.disko # disko module
+      ];
+      nixpkgs.overlays = with inputs; [
+        self.nixosOverlays.default
+      ];
       _module.args = {
         inputs = inputs;
         xlib = config.xlib;
@@ -57,6 +50,28 @@ let
         sops-nix.nixosModules.sops # sops module
       ];
 
+      _module.args = {
+        inputs = inputs;
+        xlib = config.xlib;
+      };
+    };
+  strictModule =
+    {
+      config,
+      deviceType,
+      lib,
+      xlib,
+      ...
+    }:
+    {
+      imports = with inputs; [
+        # ./essentials
+        # ./users.nix
+        ./options.nix
+        (./. + "/${deviceType}")
+        # sops-nix.nixosModules.sops
+      ];
+
       _module.args = {
         inputs = inputs;
         xlib = config.xlib;
@@ -67,5 +82,6 @@ in
   nixosModules = {
     default = defaultModule;
     public = publicModule;
+    strict = strictModule;
   };
 }

modules/server/homebox.nix

@@ -30,7 +30,7 @@ in
     "d ${configDir} 0755 homebox homebox -"
     "z ${configDir} 0755 homebox homebox -"
   ];
-  
+
   fileSystems = {
     "${varDir}" = {
       device = "${configDir}";

modules/termux/default.nix

@@ -1,9 +1,90 @@
 {
+  config,
   lib,
   pkgs,
   ...
 }:
+let
+  sshdDir = "${config.user.home}/sshd";
+  sshdTmpDir = "${config.user.home}/sshd-tmp";
+  port = 8022;
+  serviceDir = "${config.user.home}/service";
+
+  # runit run-scripts (executable store paths, linked into ~/service).
+  sshdRun = pkgs.writeScriptBin "sshd-run" ''
+    #!${pkgs.runtimeShell}
+    exec ${pkgs.openssh}/bin/sshd -f /etc/ssh/sshd_config -D
+  '';
+  svLogRun = pkgs.writeScriptBin "sv-log-run" ''
+    #!${pkgs.runtimeShell}
+    mkdir -p ./main
+    exec ${pkgs.runit}/bin/svlogd -tt ./main
+  '';
+  svStart = pkgs.writeScriptBin "sv-start" ''
+    #!${pkgs.runtimeShell}
+    exec ${pkgs.runit}/bin/runsvdir ${serviceDir}
+  '';
+in
 {
-  # imports = [
-  # ];
+  # Minimal sshd server for LAN access (e.g. `ssh epral` from other hosts).
+  # nix-on-droid has no systemd: sshd is started manually via `sshd-start`
+  # (or from Termux:Boot / a session). The host key is generated once on the
+  # first activation and kept in ~/sshd (NOT /etc — it is rebuilt on every
+  # activation).
+  environment.etc."ssh/sshd_config".text = ''
+    HostKey ${sshdDir}/ssh_host_ed25519_key
+    Port ${toString port}
+    PasswordAuthentication no
+    AllowUsers ${config.user.userName}
+  '';
+
+  # Generate the host key on first activation (idempotent).
+  build.activation.sshd = ''
+    if [[ ! -d "${sshdDir}" ]]; then
+      $DRY_RUN_CMD rm -rf "${sshdTmpDir}"
+      $DRY_RUN_CMD mkdir -p "${sshdTmpDir}"
+      $VERBOSE_ECHO "Generating sshd host key..."
+      $DRY_RUN_CMD ${pkgs.openssh}/bin/ssh-keygen -t ed25519 -f "${sshdTmpDir}/ssh_host_ed25519_key" -N ""
+      $DRY_RUN_CMD mv "${sshdTmpDir}" "${sshdDir}"
+    fi
+  '';
+
+  # nix-on-droid's session-init adds ~/.nix-defexpr/channels to NIX_PATH
+  # unconditionally; nix warns about the missing dir on every invocation.
+  # Making it exist silences the warning. Must be done in activation (not
+  # home-manager): ~/.nix-defexpr/channels is a symlink into
+  # ~/.local/state/nix/profiles/channels (dangling until it exists), which
+  # home-manager cannot link into. mkdir -p refuses to traverse a dangling
+  # symlink, so create the real target dir instead.
+  build.activation.nixdefexpr = ''
+    $DRY_RUN_CMD mkdir -p "${config.user.home}/.local/state/nix/profiles/channels/nixpkgs"
+    $DRY_RUN_CMD touch "${config.user.home}/.local/state/nix/profiles/channels/nixpkgs/.keep"
+  '';
+
+  # runit service tree: ~/service/<name>/{run,log/run}. run/ and log/run are
+  # symlinks into the nix store (read-only is fine; runsvdir writes only to
+  # the <name>/supervise dirs). /etc/service is symlinked for `sv status`.
+  # NOTE: tailscaled was removed — nixpkgs' linux build cannot run inside
+  # proot (SELinux blocks netlink; needs GOOS=android or root). Re-add only
+  # if that gets solved.
+  build.activation.services = ''
+    $DRY_RUN_CMD rm -rf ${serviceDir}/tailscaled
+    $DRY_RUN_CMD mkdir -p ${serviceDir}/sshd/log
+    $DRY_RUN_CMD ln -sfn ${sshdRun}/bin/sshd-run ${serviceDir}/sshd/run
+    $DRY_RUN_CMD ln -sfn ${svLogRun}/bin/sv-log-run ${serviceDir}/sshd/log/run
+    $DRY_RUN_CMD ln -sfn ${serviceDir} /etc/service
+  '';
+
+  environment.packages = [
+    pkgs.runit
+
+    # one command brings up all supervised services (sshd, ...)
+    svStart
+
+    # manual fallback for sshd only
+    (pkgs.writeScriptBin "sshd-start" ''
+      #!${pkgs.runtimeShell}
+      exec ${pkgs.openssh}/bin/sshd -f /etc/ssh/sshd_config -D "$@"
+    '')
+  ];
 }