feat: add Tauon from latest package pin

README.md

@@ -16,7 +16,7 @@ Flat, explicit NixOS modules with locked inputs. Required setup belongs here—n
 | `tools.nix`, `network.nix` | Development toolkit, terminal/shell, rootless Podman, VPN/proxy clients, local Tor service and network diagnostics |
 | `colors.nix`, `wallpaper.nix`, `wallpaper.svg` | Shared One Ring palette, hash-pinned wallpaper and original fallback artwork |
 | `desktop.nix`, `hyprland.lua`, `anyrun.css`, `swaync.css`, `desktop-help.py`, `desktop-actions.py` | Session/bar, launchers, described help, capture, clipboard, notifications, lock/idle and styling |
-| `apps.nix`, `element-nightly.nix` | Firefox ESR, Tor Browser, KeePassXC, Thunderbird, Steam, pinned Element Nightly, Slack, file/media viewers and MIME defaults |
+| `apps.nix`, `element-nightly.nix` | Firefox ESR, Tor Browser, KeePassXC, Thunderbird, Steam, pinned Element Nightly, Slack, Tauon, file/media viewers and MIME defaults |
 | `neovim.nix`, `neovim-test.lua` | Unmodified upstream editor deployment and opt-in native runtime audit |
 | `updates.nix`, `update-system.sh`, `update-test.py` | Shared dev-owned checkouts, daily boot-staged updates and failure/concurrency regression tests |
 | `switch-system.sh`, `switch-test.py` | Same installed manual apply/preview command on both hosts, with host identity supplied by Nix |
@@ -242,6 +242,12 @@ Manual refresh: `nix flake update nixpkgs home-manager nixpkgs-latest`, review `
 
 ## Editor and application data
 
+**Tauon** is installed for `dev` from `nixpkgs-latest` (Nixpkgs master), with the
+exact snapshot recorded in `flake.lock`. The current pin provides **12.0.0**,
+matching the latest upstream stable release when added. It advances through the
+existing daily input-update workflow. Launch `tauon` or choose **Tauon**
+in the application launcher after applying; existing MIME defaults are unchanged.
+
 Neovim imports [the existing neovim-dots source](https://git.cyber.ayyalasomayajula.net/marsultor/neovim-dots), pinned to `380eb86778a7c53a0f1c18e84f14037456155347`. Lua, AstroNvim, Lazy, Mason, plugins and keymaps are unchanged. No Nixvim, replacement loader or plugin-manager migration.
 
 Home Manager links configuration files under `~/.config/nvim`. Lazy's writable lock lives under `~/.local/state/nvim/locks/<revision>.json`, seeded once per dotfile revision. An earlier manual checkout is preserved at `~/projects/neovim-dots-before-nix`; activation refuses to overwrite an existing backup. The host input is reproducible; Lazy/Mason's mutable runtime downloads are not claimed to be fully Nix-reproducible.

apps.nix

@@ -1,5 +1,6 @@
 {
   config,
+  inputs,
   lib,
   pkgs,
   ...
@@ -7,6 +8,11 @@
 
 let
   c = import ./colors.nix;
+  # Tauon follows the fast-moving pin without overlaying the system libraries.
+  latest = import inputs.nixpkgs-latest {
+    inherit (pkgs.stdenv.hostPlatform) system;
+    config = pkgs.config;
+  };
   elementNightly = import ./element-nightly.nix { inherit pkgs; };
   browserAddon = pkgs.fetchurl {
     name = "keepassxc-browser-1.10.3.xpi";
@@ -106,11 +112,17 @@ in
       thunderbird
       file-roller
       imv
+      latest.tauon
       # Electron does not reliably detect a keyring under Hyprland. Use the
       # KeePassXC Secret Service explicitly; never fall back to basic_text.
       elementNightly
       slack
     ];
+    # Fix the pinned package's stale launcher command, preserving its metadata.
+    xdg.dataFile."applications/tauonmb.desktop".source = pkgs.runCommand "tauonmb.desktop" { } ''
+      substitute ${latest.tauon}/share/applications/tauonmb.desktop "$out" \
+        --replace-quiet 'Exec=tauonmb ' 'Exec=${lib.getExe latest.tauon} '
+    '';
     programs.mpv = {
       enable = true;
       config = {

flake.nix

@@ -10,7 +10,7 @@
       inputs.nixpkgs.follows = "nixpkgs";
     };
 
-    # Fast-moving developer tools can advance ahead of the tested channel.
+    # Fast-moving standalone apps/tools can advance ahead of the tested channel.
     # flake.lock still records the exact resolved snapshot.
     nixpkgs-latest.url = "github:NixOS/nixpkgs/master";