diff --git a/assets/zed/settings.json b/assets/zed/settings.json
new file mode 100644
index 0000000..e48db6f
--- /dev/null
+++ b/assets/zed/settings.json
@@ -0,0 +1,53 @@
+// Zed settings — tracked in dotfiles, symlinked into ~/.config/zed/settings.json
+// by home-manager (xdg.configFile in nixos/home/danny/home.nix).
+//
+// Because this is a symlink to a nix-store file, editing it from inside Zed
+// will fail (read-only). Edit THIS file in dotfiles, commit, and rebuild
+// (`darwin-rebuild switch --flake .`). To see Zed's full default settings,
+// run `zed: open default settings` from the command palette.
+{
+  "sticky_scroll": {
+    "enabled": true
+  },
+  "edit_predictions": {
+    "provider": "ollama"
+  },
+  "buffer_font_family": "JetBrains Mono",
+  "cli_default_open_behavior": "existing_window",
+  "project_panel": {
+    "dock": "left"
+  },
+  "outline_panel": {
+    "dock": "left"
+  },
+  "collaboration_panel": {
+    "dock": "left"
+  },
+  "git_panel": {
+    "dock": "left"
+  },
+  "agent": {
+    "dock": "right",
+    "default_model": {
+      "provider": "ollama",
+      "model": "llama3.2:latest"
+    }
+  },
+  "disable_ai": false,
+  "minimap": {
+    "show": "auto"
+  },
+  "telemetry": {
+    "diagnostics": false,
+    "metrics": false
+  },
+  "base_keymap": "VSCode",
+  "vim_mode": true,
+  "ui_font_size": 16,
+  "buffer_font_size": 15,
+  "theme": {
+    "mode": "system",
+    "light": "One Light",
+    "dark": "One Dark"
+  }
+}
diff --git a/nixos/fish.nix b/nixos/fish.nix
index 9d04f51..1d72d26 100644
--- a/nixos/fish.nix
+++ b/nixos/fish.nix
@@ -24,6 +24,38 @@
 
       set fish_greeting 🐟: (set_color yellow; date +%T; set_color green; date --iso-8601 2>/dev/null; or date +%F; set_color normal)
 
+      # gco: smart `git checkout` — if the branch is checked out in another
+      # worktree, cd there instead of failing with "already used by worktree at".
+      function gco --description 'git checkout, but cd into worktree if the branch lives there'
+        if test (count $argv) -eq 0
+          git checkout
+          return $status
+        end
+
+        set -l branch $argv[1]
+        set -l target_ref "refs/heads/$branch"
+        set -l wt_path ""
+        set -l current_wt ""
+        for line in (git worktree list --porcelain 2>/dev/null)
+          switch $line
+            case 'worktree *'
+              set current_wt (string replace -r '^worktree ' "" -- $line)
+            case "branch $target_ref"
+              set wt_path $current_wt
+              break
+          end
+        end
+
+        set -l here (git rev-parse --show-toplevel 2>/dev/null)
+        if test -n "$wt_path"; and test "$wt_path" != "$here"
+          echo "→ cd $wt_path (branch '$branch' is checked out in another worktree)"
+          cd $wt_path
+          return $status
+        end
+
+        git checkout $argv
+      end
+
       # Alacritty palette follows macOS appearance; refresh when opening a shell (LaunchAgent also polls).
       if test (uname -s) = Darwin
         bash ~/dotfiles/scripts/alacritty-sync-system-theme.sh >/dev/null 2>&1 &
diff --git a/nixos/neovim.nix b/nixos/neovim.nix
index 75b2335..51ae100 100644
--- a/nixos/neovim.nix
+++ b/nixos/neovim.nix
@@ -58,6 +58,39 @@
         end,
       })
 
+      -- Treesitter highlighting: parser-driven syntax highlighting (richer
+      -- than the regex-based default). Leaving `indent` off — it's still
+      -- buggy in several languages (python, yaml).
+      require'nvim-treesitter.configs'.setup {
+        highlight = { enable = true },
+      }
+
+      -- Sticky scroll: pin enclosing scopes (functions, classes, YAML keys,
+      -- etc.) to the top of the window as you scroll deeper. Same idea as
+      -- Zed/VS Code's "Sticky Scroll". `mode = 'topline'` matches Zed's
+      -- "scrolled past" feel; switch to 'cursor' if you'd rather it track
+      -- the cursor instead of the viewport.
+      require'treesitter-context'.setup {
+        enable = true,
+        max_lines = 5,
+        mode = 'topline',
+        trim_scope = 'outer',
+      }
+
+      -- Fish: expand tabs to spaces. Fish renders raw \t in the commandline
+      -- as the Unicode glyph ␉ (U+2409) and wrap-indents each line to the
+      -- column of the opening quote, which mangles Alt-E multiline edits.
+      -- Using spaces sidesteps the issue entirely.
+      vim.api.nvim_create_autocmd("FileType", {
+        pattern = "fish",
+        callback = function()
+          vim.opt_local.expandtab = true
+          vim.opt_local.tabstop = 2
+          vim.opt_local.shiftwidth = 2
+          vim.opt_local.softtabstop = 2
+        end,
+      })
+
       -- Keymaps
       vim.keymap.set("n", "S", ":%s//g<Left><Left>", { desc = "Replace all" })
       vim.keymap.set("n", "<leader>w", ":w<CR>", { desc = "Save file" })
@@ -73,6 +106,8 @@
       catppuccin-nvim # theme
       goyo-vim        # write prose
       limelight-vim   # prose paragraph highlighter
+      nvim-treesitter.withAllGrammars  # parsers (also makes vim.treesitter.foldexpr work for markdown)
+      nvim-treesitter-context          # sticky scroll: pin parent scopes at top of window
     ];
   };
 }