diff --git a/modules/home/agents/home-claude.ulu.nix b/modules/home/agents/home-claude.ulu.nix
index bac4f41..867a46b 100644
--- a/modules/home/agents/home-claude.ulu.nix
+++ b/modules/home/agents/home-claude.ulu.nix
@@ -76,8 +76,8 @@
         "gh workflow list*"
         "gh workflow view*"
 
+        # not `nix develop*`: `nix develop -c <cmd>` would run anything
         "nix build*"
-        "nix develop*"
         "nix eval*"
         "nix flake archive*"
         "nix flake check*"
@@ -360,6 +360,10 @@
           env.CLAUDE_CODE_FORCE_GLOBAL_CACHE = "1";
           env.MCP_CONNECTION_NONBLOCKING = "1";
           env.USE_BUILTIN_RIPGREP = "0";
+          # rea mcp ghidra provider
+          env.GHIDRA_INSTALL_DIR = "${pkgs.ghidra}/lib/ghidra";
+          env.GHIDRA_HEADLESS_MAXMEM = "6G";
+          env.REA_GHIDRA_STARTUP_TIMEOUT_MS = "3600000";
 
           # bittersweet
           alwaysThinkingEnabled = true;
diff --git a/modules/home/home-browser-zen.ulu.nix b/modules/home/home-browser-zen.ulu.nix
index a40531e..d5749b7 100644
--- a/modules/home/home-browser-zen.ulu.nix
+++ b/modules/home/home-browser-zen.ulu.nix
@@ -39,7 +39,6 @@
             "firefox-extension@steamdb.info"
             "chrome-mask@overengineer.dev"
             "{a4cc20af-d30a-4758-a799-2089ce45f452}"
-            "plasma-browser-integration@kde.org"
           ] mkExtension;
         };
         profiles.Yamura = {
diff --git a/modules/home/home-discord-plugins.ulu.nix b/modules/home/home-discord-plugins.ulu.nix
index decbba2..8a84e8a 100644
--- a/modules/home/home-discord-plugins.ulu.nix
+++ b/modules/home/home-discord-plugins.ulu.nix
@@ -26,7 +26,6 @@
           };
           equibopStreamFixes.enable = true;
           equicordHelper.enable = true;
-          fakeNitro.enable = true;
           fakeProfileThemes.enable = true;
           fixSpotifyEmbeds = {
             enable = true;
@@ -35,11 +34,6 @@
           fixYoutubeEmbeds.enable = true;
           gifCollections.enable = true;
           messageLinkEmbeds.enable = true;
-          messageLogger = {
-            enable = true;
-            ignoreBots = false;
-          };
-          messageLoggerEnhanced.enable = true;
           newPluginsManager.enable = true;
           noF1.enable = true;
           noNitroUpsell.enable = true;
@@ -60,7 +54,6 @@
           };
           showHiddenThings.enable = true;
           showTimeoutDuration.enable = true;
-          spotifyCrack.enable = true;
           streamingCodecDisabler = {
             enable = true;
             disableAv1Codec = true;
diff --git a/modules/home/home-file-manager-actions.ulu.nix b/modules/home/home-file-manager-actions.ulu.nix
index fdbb5de..551c38b 100644
--- a/modules/home/home-file-manager-actions.ulu.nix
+++ b/modules/home/home-file-manager-actions.ulu.nix
@@ -34,7 +34,14 @@
             fi
           }
           trap finish EXIT
-          stem() { printf '%s' "''${1%.*}"; }
+          # path without the extension; only the file name's own dot counts
+          # (not one in a directory name, not a dotfile's leading dot)
+          stem() {
+            d=$(dirname -- "$1")
+            b=$(basename -- "$1")
+            case "$b" in ?*.*) b="''${b%.*}" ;; esac
+            printf '%s/%s' "$d" "$b"
+          }
           resolve_dnxhr() {
             profile="$1"; shift
             for f in "$@"; do
@@ -203,9 +210,21 @@
               notify "PDF rendered" "$# document(s)"
               ;;
             pdf-merge)
-              require_count 2 "$@" 2>/dev/null || true
-              pdfunite "$@" merged.pdf
-              notify "PDFs merged" "merged.pdf"
+              if [ "$#" -lt 2 ]; then
+                notify-send -a Dolphin -u critical "action failed" \
+                  "select at least 2 PDFs" || true
+                exit 2
+              fi
+              # next to the first PDF, never over an existing file
+              dir=$(dirname -- "$1")
+              out="$dir/merged.pdf"
+              n=1
+              while [ -e "$out" ]; do
+                out="$dir/merged-$n.pdf"
+                n=$((n + 1))
+              done
+              pdfunite "$@" "$out"
+              notify "PDFs merged" "$(basename -- "$out")"
               ;;
             compare)
               require_count 2 "$@"
diff --git a/modules/home/home-ghidra.ulu.nix b/modules/home/home-ghidra.ulu.nix
new file mode 100644
index 0000000..acbd221
--- /dev/null
+++ b/modules/home/home-ghidra.ulu.nix
@@ -0,0 +1,9 @@
+{ ... }:
+{
+  flake.homeModules.home-ghidra =
+    { pkgs, ... }:
+    {
+      home.packages = [ pkgs.ghidra ];
+      home.sessionVariables.GHIDRA_INSTALL_DIR = "${pkgs.ghidra}/lib/ghidra";
+    };
+}
diff --git a/modules/home/home-ghostty.ulu.nix b/modules/home/home-ghostty.ulu.nix
index fdd2080..6d6d0df 100644
--- a/modules/home/home-ghostty.ulu.nix
+++ b/modules/home/home-ghostty.ulu.nix
@@ -1,11 +1,9 @@
 { ... }:
 {
   flake.homeModules.home-ghostty =
-    { pkgs, lib, ... }:
+    { pkgs, ... }:
     let
-      isDarwin = pkgs.stdenv.isDarwin;
-
-      linuxKeybinds = [
+      keybinds = [
         "alt+r=reload_config"
 
         "ctrl+shift+q=close_surface"
@@ -38,36 +36,6 @@
         "ctrl+shift+e=equalize_splits"
       ];
 
-      darwinKeybinds = [
-        "cmd+s>r=reload_config"
-        "cmd+s>x=close_surface"
-        "cmd+s>n=new_window"
-
-        "cmd+s>c=new_tab"
-        "cmd+s>shift+l=next_tab"
-        "cmd+s>shift+h=previous_tab"
-        "cmd+s>comma=move_tab:-1"
-        "cmd+s>period=move_tab:1"
-
-        "cmd+s>1=goto_tab:1"
-        "cmd+s>2=goto_tab:2"
-        "cmd+s>3=goto_tab:3"
-        "cmd+s>4=goto_tab:4"
-        "cmd+s>5=goto_tab:5"
-        "cmd+s>6=goto_tab:6"
-        "cmd+s>7=goto_tab:7"
-        "cmd+s>8=goto_tab:8"
-        "cmd+s>9=goto_tab:9"
-
-        "cmd+s>\\=new_split:right"
-        "cmd+s>-=new_split:down"
-        "cmd+s>h=goto_split:left"
-        "cmd+s>j=goto_split:bottom"
-        "cmd+s>k=goto_split:top"
-        "cmd+s>l=goto_split:right"
-        "cmd+s>z=toggle_split_zoom"
-        "cmd+s>e=equalize_splits"
-      ];
     in
     {
       home.packages = [ pkgs.nerd-fonts.profont ];
@@ -95,10 +63,7 @@
           adjust-cell-height = "35%";
           background-opacity = 0.96;
 
-          keybind = linuxKeybinds ++ lib.optionals isDarwin darwinKeybinds;
-        }
-        // lib.optionalAttrs isDarwin {
-          macos-titlebar-style = "transparent";
+          keybind = keybinds;
         };
       };
     };
diff --git a/modules/home/home-jujutsu-signing.ulu.nix b/modules/home/home-jujutsu-signing.ulu.nix
new file mode 100644
index 0000000..4cea245
--- /dev/null
+++ b/modules/home/home-jujutsu-signing.ulu.nix
@@ -0,0 +1,17 @@
+{ ... }:
+{
+  flake.homeModules.home-jujutsu-signing =
+    { ... }:
+    {
+      # Same GPG key as common-git. Commits are signed when pushed rather than
+      # on every working-copy rewrite, so gpg isn't called on each snapshot.
+      programs.jujutsu.settings = {
+        signing = {
+          backend = "gpg";
+          key = "5EA48F7312A42B84";
+          behavior = "drop";
+        };
+        git.sign-on-push = true;
+      };
+    };
+}
diff --git a/modules/home/home-shell-tools.ulu.nix b/modules/home/home-shell-tools.ulu.nix
index 6315516..261756c 100644
--- a/modules/home/home-shell-tools.ulu.nix
+++ b/modules/home/home-shell-tools.ulu.nix
@@ -3,7 +3,11 @@
   flake.homeModules.home-shell-tools =
     { ... }:
     {
-      programs.starship.enable = true;
+      programs.starship = {
+        enable = true;
+        # nushell has its own jj prompt (home-nushell-prompt)
+        enableNushellIntegration = false;
+      };
       programs.fzf.enable = true;
       programs.zoxide = {
         enable = true;
diff --git a/modules/home/home-zsh.ulu.nix b/modules/home/home-zsh.ulu.nix
index a027f73..0726c98 100644
--- a/modules/home/home-zsh.ulu.nix
+++ b/modules/home/home-zsh.ulu.nix
@@ -21,8 +21,6 @@
           zstyle ':completion:*' menu select
           zstyle ':completion:*' matcher-list 'm:{a-z}={A-Za-z}'
 
-          export MESA_SHADER_CACHE_MAX_SIZE=2G
-          export MESA_SHADER_CACHE_DIR=/tmp/mesa_shader_cache
           export PATH="$HOME/.local/bin:$PATH"
         '';
       };
diff --git a/modules/home/nu/home-nushell.ulu.nix b/modules/home/nu/home-nushell.ulu.nix
index b74ad5d..b92c53f 100644
--- a/modules/home/nu/home-nushell.ulu.nix
+++ b/modules/home/nu/home-nushell.ulu.nix
@@ -49,8 +49,6 @@
         };
 
         environmentVariables = {
-          MESA_SHADER_CACHE_MAX_SIZE = "2G";
-          MESA_SHADER_CACHE_DIR = "/tmp/mesa_shader_cache";
           FZF_DEFAULT_OPTS = "--height 40% --layout=reverse --border";
           FZF_DEFAULT_COMMAND = "fd --type f --hidden --follow --exclude .git";
         };
diff --git a/modules/home/theme/home-theme-discord.ulu.nix b/modules/home/theme/home-theme-discord.ulu.nix
index 2334741..de275b9 100644
--- a/modules/home/theme/home-theme-discord.ulu.nix
+++ b/modules/home/theme/home-theme-discord.ulu.nix
@@ -136,9 +136,14 @@
       '';
     in
     {
-      xdg.configFile."legcord/quickCss.css".text = ''
-        ${builtins.readFile ./discord-system24.css}
-        ${colors}
-      '';
+      # nixcord owns the client's settings.json, so a theme enabled from the
+      # UI is lost on restart; enable it here instead.
+      programs.nixcord.config = {
+        themes.kemuri-system24 = ''
+          ${builtins.readFile ./discord-system24.css}
+          ${colors}
+        '';
+        enabledThemes = [ "kemuri-system24.css" ];
+      };
     };
 }
diff --git a/modules/home/vscode/home-vscode.ulu.nix b/modules/home/vscode/home-vscode.ulu.nix
index 096303f..dbb112b 100644
--- a/modules/home/vscode/home-vscode.ulu.nix
+++ b/modules/home/vscode/home-vscode.ulu.nix
@@ -169,9 +169,7 @@
           "search.followSymlinks" = false;
 
           # ── terminal: nushell, same colours as ghostty ────────────────────
-          "terminal.integrated.defaultProfile.osx" = "nu";
           "terminal.integrated.defaultProfile.linux" = "nu";
-          "terminal.integrated.profiles.osx".nu.path = "${pkgs.nushell}/bin/nu";
           "terminal.integrated.profiles.linux".nu.path = "${pkgs.nushell}/bin/nu";
           "terminal.integrated.fontFamily" = "'JetBrainsMono Nerd Font', monospace";
           "terminal.integrated.fontSize" = 13;
@@ -186,12 +184,7 @@
           "terminal.integrated.shellIntegration.decorationsEnabled" = "never";
           "terminal.integrated.enableVisualBell" = false;
 
-          # ── scm (jj colocated: the git view reads the git side) ───────────
-          "git.confirmSync" = false;
-          "git.enableSmartCommit" = true;
-          "git.autofetch" = false;
-          "git.openRepositoryInParentFolders" = "never";
-          "git.decorations.enabled" = true;
+          # ── scm (the git extension is off, jjk drives it: home-vscode-jujutsu)
           "scm.defaultViewMode" = "list";
           "scm.diffDecorations" = "gutter";
           "diffEditor.ignoreTrimWhitespace" = false;