diff --git a/.config/.vimrc b/.config/.vimrc
deleted file mode 100644
index b4a9ccb..0000000
--- a/.config/.vimrc
+++ /dev/null
@@ -1,194 +0,0 @@
-" ========================================
-" Options
-" ========================================
-
-set encoding=UTF-8
-set spelllang=en_us,de_de,es_es
-set nohlsearch " Disable highlight on search
-set number " Enable line numbers
-set mouse=a " Enable mouse mode
-set breakindent " Enable break indent
-set undofile " Save undo history
-set ignorecase " Case-insensitive searching unless \C or capital in search
-set smartcase " Enable smart case
-set signcolumn=yes " Keep signcolumn on by default
-set updatetime=250 " Decrease update time
-set timeoutlen=300 " Time to wait for a mapped sequence to complete (in milliseconds)
-set nobackup " Don't create a backup file
-set nowritebackup " Don't write backup before overwriting
-set completeopt=menuone,noselect " Better completion experience
-set whichwrap+=<,>,[,],h,l " Allow certain keys to move to the next line
-set nowrap " Display long lines as one line
-set linebreak " Don't break words when wrapping
-set scrolloff=8 " Keep 8 lines above/below cursor
-set sidescrolloff=8 " Keep 8 columns to the left/right of cursor
-set relativenumber " Use relative line numbers
-set numberwidth=4 " Number column width
-set shiftwidth=4 " Spaces per indentation
-set tabstop=4 " Spaces per tab
-set softtabstop=4 " Spaces per tab during editing ops
-set expandtab " Convert tabs to spaces
-set nocursorline " Don't highlight the current line
-set splitbelow " Horizontal splits below current window
-set splitright " Vertical splits to the right
-set noswapfile " Don't use a swap file
-set smartindent " Smart indentation
-set showtabline=2 " Always show tab line
-set backspace=indent,eol,start " Configurable backspace behavior
-set pumheight=10 " Popup menu height
-set conceallevel=0 " Make `` visible in markdown
-set fileencoding=utf-8 " File encoding
-set cmdheight=1 " Command line height
-set autoindent " Auto-indent new lines
-set shortmess+=c " Don't show completion menu messages
-set iskeyword+=- " Treat hyphenated words as whole words
-set showmatch " show the matching part of pairs [] {} and ()
-set laststatus=2 " Show status bar
-set statusline=%f " Path to the file
-set statusline+=%= " Switch to the right side
-set statusline+=%l " Current line
-set statusline+=/ " Separator
-set statusline+=%L " Total lines
-
-
-" ========================================
-" Keymaps
-" ========================================
-
-" Set leader key
-let mapleader = " "
-let maplocalleader = " "
-
-" Disable the spacebar key's default behavior in Normal and Visual modes
-nnoremap <Space> <Nop>
-vnoremap <Space> <Nop>
-
-" Allow moving the cursor through wrapped lines with j, k
-nnoremap <expr> k v:count == 0 ? 'gk' : 'k'
-nnoremap <expr> j v:count == 0 ? 'gj' : 'j'
-
-" clear highlights
-nnoremap <Esc> :noh<CR>
-
-" save file
-nnoremap <C-s> :w<CR>
-
-" save file without auto-formatting
-nnoremap <leader>sn :noautocmd w<CR>
-
-" quit file
-nnoremap <C-q> :q<CR>
-
-" delete single character without copying into register
-nnoremap x "_x
-
-" Vertical scroll and center
-nnoremap <C-d> <C-d>zz
-nnoremap <C-u> <C-u>zz
-
-" Find and center
-nnoremap n nzzzv
-nnoremap N Nzzzv
-
-" Resize with arrows
-nnoremap <Up> :resize -2<CR>
-nnoremap <Down> :resize +2<CR>
-nnoremap <Left> :vertical resize -2<CR>
-nnoremap <Right> :vertical resize +2<CR>
-
-" Navigate buffers
-nnoremap <Tab> :bnext<CR>
-nnoremap <S-Tab> :bprevious<CR>
-nnoremap <leader>sb :buffers<CR>:buffer<Space>
-
-" increment/decrement numbers
-nnoremap <leader>+ <C-a>
-nnoremap <leader>- <C-x>
-
-" window management
-nnoremap <leader>v <C-w>v
-nnoremap <leader>h <C-w>s
-nnoremap <leader>se <C-w>=
-nnoremap <leader>xs :close<CR>
-
-" Navigate between splits
-nnoremap <C-k> :wincmd k<CR>
-nnoremap <C-j> :wincmd j<CR>
-nnoremap <C-h> :wincmd h<CR>
-nnoremap <C-l> :wincmd l<CR>
-
-" tabs
-nnoremap <leader>to :tabnew<CR>
-nnoremap <leader>tx :tabclose<CR>
-nnoremap <leader>tn :tabn<CR>
-nnoremap <leader>tp :tabp<CR>
-
-nnoremap <leader>x :bdelete<CR>
-nnoremap <leader>b :enew<CR>
-
-" toggle line wrapping
-nnoremap <leader>lw :set wrap!<CR>
-
-" Press jk fast to exit insert mode
-inoremap jk <ESC>
-inoremap kj <ESC>
-
-" Stay in indent mode
-" vnoremap < <gv
-" vnoremap > >gv
-
-" Keep last yanked when pasting
-vnoremap p "_dP
-
-" Explicitly yank to system clipboard (highlighted and entire row)
-noremap <leader>y "+y
-noremap <leader>Y "+Y
-
-" Open file explorer
-noremap <silent> <leader>e :Lex<CR>
-
-" Make W w on save
-noremap :W :w
-
-" ========================================
-" Other
-" ========================================
-
-" Syntax highlighting
-syntax on
-
-" Colorscheme
-" colorscheme industry
-colorscheme wildcharm
-set background=dark
-" hi Normal ctermbg=NONE guibg=NONE
-" hi NonText ctermbg=NONE guibg=NONE guifg=NONE ctermfg=NONE
-" hi VertSplit guibg=NONE guifg=NONE ctermbg=NONE ctermfg=NONE
-
-" Sync clipboard with OS
-set clipboard=unnamedplus
-
-" True colors
-if !has('gui_running') && &term =~ '\%(screen\|tmux\)'
-  let &t_8f = "\<Esc>[38;2;%lu;%lu;%lum"
-  let &t_8b = "\<Esc>[48;2;%lu;%lu;%lum"
-endif
-if has('termguicolors')
-  set termguicolors
-endif
-
-" Use a line cursor within insert mode and a block cursor everywhere else.
-let &t_SI = "\e[6 q"
-let &t_EI = "\e[2 q"
-
-" Netrw
-let g:netrw_banner = 0
-let g:netrw_liststyle = 3
-let g:netrw_browse_split = 4
-let g:netrw_altv = 1
-let g:netrw_winsize = 25
-" Use 'l' instead of <CR> to open files
-augroup netrw_setup | au!
-    au FileType netrw nmap <buffer> l <CR>
-augroup END
-
diff --git a/.config/nvim/lua/brian/core/keymaps.lua b/.config/nvim/lua/brian/core/keymaps.lua
index 17be5fd..9763414 100644
--- a/.config/nvim/lua/brian/core/keymaps.lua
+++ b/.config/nvim/lua/brian/core/keymaps.lua
@@ -174,7 +174,9 @@ local function angular_switch(section)
   local is_ts = file:match '%.component%.ts$'
 
   -- If we're in a .ts file, check for inline sections before switching files
-  if is_ts and (section == 'template' or section == 'styles' or section == 'ts') then
+  if
+    is_ts and (section == 'template' or section == 'styles' or section == 'ts')
+  then
     local lines = vim.api.nvim_buf_get_lines(0, 0, -1, false)
     local pattern
     if section == 'template' then
@@ -213,8 +215,7 @@ local function angular_switch(section)
     target = base .. '.component.html'
   elseif section == 'styles' then
     local scss = base .. '.component.scss'
-    target = vim.fn.filereadable(scss) == 1 and scss
-      or base .. '.component.css'
+    target = vim.fn.filereadable(scss) == 1 and scss or base .. '.component.css'
   elseif section == 'spec' then
     target = base .. '.component.spec.ts'
   end
diff --git a/.config/nvim/lua/brian/core/options.lua b/.config/nvim/lua/brian/core/options.lua
index a9bf456..7ddba4c 100644
--- a/.config/nvim/lua/brian/core/options.lua
+++ b/.config/nvim/lua/brian/core/options.lua
@@ -42,17 +42,20 @@ vim.opt.iskeyword:append '-' -- hyphenated words recognized by searches
 vim.opt.formatoptions:remove { 'c', 'r', 'o' } -- don't insert the current comment leader automatically for auto-wrapping comments using 'textwidth', hitting <Enter> in insert mode, or hitting 'o' or 'O' in normal mode.
 vim.opt.runtimepath:remove '/usr/share/vim/vimfiles' -- separate vim plugins from neovim in case vim still in use
 
--- Neovim 0.12 changed directive captures from TSNode to TSNode[] (arrays).
--- nvim-treesitter predicates do match[capture_id] expecting a single TSNode,
--- but now receive a table. The nil guard passes, then get_node_text calls
--- node:range(true) on a plain table which has no range method and crashes.
--- Unwrap the array so nvim-treesitter keeps working until it is patched upstream.
-local _get_node_text = vim.treesitter.get_node_text
-vim.treesitter.get_node_text = function(node, source, opts)
-  if not node then return '' end
-  if type(node) == 'table' then
-    node = node[1]
-    if not node then return '' end
+-- Temporary compatibility workaround for Neovim 0.12 directive captures.
+-- Keep this scoped to 0.12 so later releases use the upstream implementation.
+if vim.version().minor == 12 then
+  local get_node_text = vim.treesitter.get_node_text
+  vim.treesitter.get_node_text = function(node, source, opts)
+    if not node then
+      return ''
+    end
+    if type(node) == 'table' then
+      node = node[1]
+      if not node then
+        return ''
+      end
+    end
+    return get_node_text(node, source, opts)
   end
-  return _get_node_text(node, source, opts)
 end
diff --git a/.config/nvim/lua/brian/lsp.lua b/.config/nvim/lua/brian/lsp.lua
index 2822a22..68b0ca7 100644
--- a/.config/nvim/lua/brian/lsp.lua
+++ b/.config/nvim/lua/brian/lsp.lua
@@ -12,7 +12,9 @@ end
 local function hover_if_supported()
   local bufnr = vim.api.nvim_get_current_buf()
   for _, client in ipairs(vim.lsp.get_clients { bufnr = bufnr }) do
-    if client.server_capabilities and client.server_capabilities.hoverProvider then
+    if
+      client.server_capabilities and client.server_capabilities.hoverProvider
+    then
       vim.lsp.buf.hover { border = 'rounded' }
       return
     end
@@ -58,12 +60,7 @@ vim.api.nvim_create_autocmd('LspAttach', {
     keymap.set('n', 'gt', '<cmd>Telescope lsp_type_definitions<CR>', opts) -- show lsp type definitions
 
     opts.desc = 'See available code actions'
-    keymap.set(
-      { 'n', 'v' },
-      '<leader>ca',
-      vim.lsp.buf.code_action,
-      opts
-    ) -- see available code actions, in visual mode will apply to selection
+    keymap.set({ 'n', 'v' }, '<leader>ca', vim.lsp.buf.code_action, opts) -- see available code actions, in visual mode will apply to selection
 
     opts.desc = 'Smart rename'
     keymap.set('n', '<leader>rn', vim.lsp.buf.rename, opts) -- smart rename
diff --git a/.config/nvim/lua/brian/plugins/dap.lua b/.config/nvim/lua/brian/plugins/dap.lua
index 1172145..89c1ec2 100644
--- a/.config/nvim/lua/brian/plugins/dap.lua
+++ b/.config/nvim/lua/brian/plugins/dap.lua
@@ -184,15 +184,12 @@ return {
       'DapLogPoint',
       { text = 'L', texthl = 'DiagnosticInfo', linehl = '', numhl = '' }
     )
-    vim.fn.sign_define(
-      'DapStopped',
-      {
-        text = '>',
-        texthl = 'DiagnosticOk',
-        linehl = 'DapStoppedLine',
-        numhl = '',
-      }
-    )
+    vim.fn.sign_define('DapStopped', {
+      text = '>',
+      texthl = 'DiagnosticOk',
+      linehl = 'DapStoppedLine',
+      numhl = '',
+    })
     vim.fn.sign_define(
       'DapBreakpointRejected',
       { text = 'R', texthl = 'DiagnosticError', linehl = '', numhl = '' }
diff --git a/.config/nvim/lua/brian/plugins/formatting.lua b/.config/nvim/lua/brian/plugins/formatting.lua
index dad3466..8646957 100644
--- a/.config/nvim/lua/brian/plugins/formatting.lua
+++ b/.config/nvim/lua/brian/plugins/formatting.lua
@@ -28,12 +28,11 @@ return {
         html = { 'prettierd', 'prettier', stop_after_first = true },
         htmlangular = { 'prettierd', 'prettier', stop_after_first = true },
         lua = { 'stylua' },
-        rust = { 'ast_grep' },
-        python = { 'ruff', 'black' },
-        dockerfile = { 'hadolint' },
+        rust = { 'rustfmt', lsp_format = 'fallback' },
+        python = { 'ruff_format' },
       },
       format_on_save = {
-        lsp_fallback = true,
+        lsp_format = 'fallback',
         async = false,
         timeout_ms = 1000,
       },
@@ -44,7 +43,7 @@ return {
 
     vim.keymap.set({ 'n', 'v' }, '<leader>mp', function()
       conform.format {
-        lsp_fallback = true,
+        lsp_format = 'fallback',
         async = false,
         timeout_ms = 1000,
       }
diff --git a/.config/nvim/lua/brian/plugins/mason.lua b/.config/nvim/lua/brian/plugins/mason.lua
index f27206e..03b68ab 100644
--- a/.config/nvim/lua/brian/plugins/mason.lua
+++ b/.config/nvim/lua/brian/plugins/mason.lua
@@ -52,11 +52,13 @@ local function dedupe(list)
   return out
 end
 
-local tool_installer_list = dedupe(vim.list_extend(vim.deepcopy(tools), lsp_servers))
+local tool_installer_list =
+  dedupe(vim.list_extend(vim.deepcopy(tools), lsp_servers))
 
 return {
   {
     'mason-org/mason-lspconfig.nvim',
+    cond = vim.env.DOTFILES_CI ~= '1',
     opts = {
       -- Only auto-enable the LSP servers we explicitly manage in this config.
       -- This avoids accidental multi-server attaches (e.g. ts_ls + vtsls),
@@ -81,6 +83,7 @@ return {
   },
   {
     'WhoIsSethDaniel/mason-tool-installer.nvim',
+    cond = vim.env.DOTFILES_CI ~= '1',
     dependencies = {
       'mason-org/mason.nvim',
     },
@@ -93,8 +96,8 @@ return {
         ['mason-null-ls'] = false,
         ['mason-nvim-dap'] = false,
       },
-      run_on_start = true,
-      start_delay = 0,
+      run_on_start = vim.env.DOTFILES_CI ~= '1',
+      start_delay = 3000,
     },
   },
 }
diff --git a/.config/nvim/lua/brian/plugins/nvim-tree.lua b/.config/nvim/lua/brian/plugins/nvim-tree.lua
index 0d450e6..2c4af4e 100644
--- a/.config/nvim/lua/brian/plugins/nvim-tree.lua
+++ b/.config/nvim/lua/brian/plugins/nvim-tree.lua
@@ -8,17 +8,18 @@ return {
   dependencies = {
     'nvim-tree/nvim-web-devicons',
   },
-  config = function()
-    local nvimtree = require 'nvim-tree'
-    -- disable netrw at the very start of your init.lua
+  init = function()
     vim.g.loaded_netrw = 1
     vim.g.loaded_netrwPlugin = 1
+  end,
+  config = function()
+    local nvimtree = require 'nvim-tree'
 
-    -- optionally enable 24-bit colour
     vim.opt.termguicolors = true
 
-    -- OR setup with some options
     nvimtree.setup {
+      disable_netrw = true,
+      hijack_netrw = false,
       sort = {
         sorter = 'case_sensitive',
       },
diff --git a/.config/nvim/lua/brian/plugins/treesitter.lua b/.config/nvim/lua/brian/plugins/treesitter.lua
index b5fd27b..ffafa9d 100644
--- a/.config/nvim/lua/brian/plugins/treesitter.lua
+++ b/.config/nvim/lua/brian/plugins/treesitter.lua
@@ -1,4 +1,35 @@
 -- Highlight, edit, and navigate code
+local ci = vim.env.DOTFILES_CI == '1'
+local parsers = {
+  'angular',
+  'lua',
+  'python',
+  'javascript',
+  'typescript',
+  'vimdoc',
+  'vim',
+  'regex',
+  'terraform',
+  'sql',
+  'dockerfile',
+  'toml',
+  'json',
+  'java',
+  'groovy',
+  'gitignore',
+  'graphql',
+  'yaml',
+  'make',
+  'cmake',
+  'markdown',
+  'markdown_inline',
+  'bash',
+  'tsx',
+  'css',
+  'html',
+  'rust',
+}
+
 return {
   'nvim-treesitter/nvim-treesitter',
   branch = 'master',
@@ -8,36 +39,10 @@ return {
     'nvim-treesitter/nvim-treesitter-textobjects',
   },
   opts = {
-    ensure_installed = {
-      'angular',
-      'lua',
-      'python',
-      'javascript',
-      'typescript',
-      'vimdoc',
-      'vim',
-      'regex',
-      'terraform',
-      'sql',
-      'dockerfile',
-      'toml',
-      'json',
-      'java',
-      'groovy',
-      'gitignore',
-      'graphql',
-      'yaml',
-      'make',
-      'cmake',
-      'markdown',
-      'markdown_inline',
-      'bash',
-      'tsx',
-      'css',
-      'html',
-      'rust',
-    },
-    auto_install = true,
+    ensure_installed = ci and {} or parsers,
+    auto_install = not ci,
+    parser_install_dir = ci and (vim.fn.stdpath 'cache' .. '/treesitter')
+      or nil,
     highlight = { enable = true },
     indent = { enable = true },
     incremental_selection = {
diff --git a/.config/starship/starship-wave.toml b/.config/starship/starship-wave.toml
index 379cb35..6724273 100644
--- a/.config/starship/starship-wave.toml
+++ b/.config/starship/starship-wave.toml
@@ -113,29 +113,3 @@ purple = '#a292a3'
 gray = '#727169'
 black = '#181616'
 white = '#c5c9c5'
-
-[palettes.nord]
-dark_blue = '#5E81AC'
-blue = '#81A1C1'
-teal = '#88C0D0'
-red = '#BF616A'
-orange = '#D08770'
-green = '#A3BE8C'
-yellow = '#EBCB8B'
-purple = '#B48EAD'
-gray = '#434C5E'
-black = '#2E3440'
-white='#D8DEE9'
-
-[palettes.onedark]
-dark_blue='#61afef'
-blue='#56b6c2'
-red='#e06c75'
-green='#98c379'
-purple='#c678dd'
-cyan='#56b6c2'
-orange='#be5046'
-yellow='#e5c07b'
-gray='#828997'
-white ='#abb2bf'
-black='#2c323c'
diff --git a/.config/starship/starship.toml b/.config/starship/starship.toml
index af0f11f..af20134 100644
--- a/.config/starship/starship.toml
+++ b/.config/starship/starship.toml
@@ -113,29 +113,3 @@ purple = '#a292a3'
 gray = '#727169'
 black = '#181616'
 white = '#c5c9c5'
-
-[palettes.nord]
-dark_blue = '#5E81AC'
-blue = '#81A1C1'
-teal = '#88C0D0'
-red = '#BF616A'
-orange = '#D08770'
-green = '#A3BE8C'
-yellow = '#EBCB8B'
-purple = '#B48EAD'
-gray = '#434C5E'
-black = '#2E3440'
-white='#D8DEE9'
-
-[palettes.onedark]
-dark_blue='#61afef'
-blue='#56b6c2'
-red='#e06c75'
-green='#98c379'
-purple='#c678dd'
-cyan='#56b6c2'
-orange='#be5046'
-yellow='#e5c07b'
-gray='#828997'
-white ='#abb2bf'
-black='#2c323c'
diff --git a/.config/tmux/nord-theme.conf b/.config/tmux/nord-theme.conf
deleted file mode 100644
index b04942d..0000000
--- a/.config/tmux/nord-theme.conf
+++ /dev/null
@@ -1,23 +0,0 @@
-# bg="#3B4252"
-bg="default"
-default_fg="#D8DEE9"
-session_fg="#A3BE8C"
-session_selection_fg="#3B4252"
-session_selection_bg="#81A1C1"
-active_window_fg="#88C0D0"
-active_pane_border="#abb2bf"
-
-set -g status-left-length 200   # default: 10
-set -g status-right-length 200  # default: 10
-set -g status-left "#[fg=${session_fg},bold,bg=${bg}] #S #[fg=${default_fg},nobold,bg=${bg}] | "
-set -g status-right " #{cpu -i 3}   #{mem} "
-set -g status-justify left
-set -g status-style "bg=${bg}"
-set -g window-status-format "#[fg=${default_fg},bg=default] #I:#W"
-set -g window-status-current-format "#[fg=${active_window_fg},bold,bg=default]  #[underscore]#I:#W"
-set -g window-status-last-style "fg=${default_fg},bg=default"
-set -g message-command-style "bg=default,fg=${default_fg}"
-set -g message-style "bg=default,fg=${default_fg}"
-set -g mode-style "bg=${session_selection_bg},fg=${session_selection_fg}"
-set -g pane-active-border-style "fg=${active_pane_border},bg=default"
-set -g pane-border-style "fg=brightblack,bg=default"
diff --git a/.config/tmux/tmux.conf b/.config/tmux/tmux.conf
index 3cbd42b..ea26177 100644
--- a/.config/tmux/tmux.conf
+++ b/.config/tmux/tmux.conf
@@ -68,9 +68,9 @@ set -g @plugin 'tmux-plugins/tmux-continuum'    # Automatically saves sessions e
 set -g @plugin 'hendrikmi/tmux-cpu-mem-monitor' # CPU and memory info
 set -g @plugin 'tmux-plugins/tmux-yank'
 
-# Load theme from deterministic selector file written by ~/.zshrc.
-if-shell '[ -f ~/.config/tmux/current-theme.conf ]' \
-  'source-file ~/.config/tmux/current-theme.conf' \
+# Load theme from deterministic selector file generated during shell startup.
+if-shell '[ -f ~/.cache/dotfiles/tmux-theme.conf ]' \
+  'source-file ~/.cache/dotfiles/tmux-theme.conf' \
   'source-file ~/.config/tmux/dragon-theme.conf'
 
 # Resurrect
diff --git a/.config/wezterm/wezterm.lua b/.config/wezterm/wezterm.lua
index e36c6d8..5d2a063 100644
--- a/.config/wezterm/wezterm.lua
+++ b/.config/wezterm/wezterm.lua
@@ -13,12 +13,12 @@ local function env_number(name, fallback)
 	return parsed
 end
 
--- User-tunable settings live in ~/.zshrc, which writes them to env.lua
+-- User-tunable settings live in ~/.zshrc, which writes them to a cache file
 -- (GUI-launched WezTerm never sees shell exports). WezTerm watches that
 -- file and live-reloads, so editing .zshrc + opening a new shell applies.
--- Precedence: env.lua > process env > defaults.
+-- Precedence: cache file > process env > defaults.
 local user = {}
-local env_file = wezterm.home_dir .. "/.config/wezterm/env.lua"
+local env_file = wezterm.home_dir .. "/.cache/dotfiles/wezterm-env.lua"
 local ok, loaded = pcall(dofile, env_file)
 if ok and type(loaded) == "table" then
 	user = loaded
diff --git a/.config/zed/keymap.json b/.config/zed/keymap.json
deleted file mode 100644
index ac90cea..0000000
--- a/.config/zed/keymap.json
+++ /dev/null
@@ -1,107 +0,0 @@
-// Zed keymap
-//
-// This carries over the Neovim shortcuts that map cleanly onto Zed.
-// Leader mappings use Zed's Vim mode sequence support.
-[
-  {
-    "context": "Editor && !menu && vim_mode == normal",
-    "bindings": {
-      "ctrl-s": "workspace::SaveAll",
-      "ctrl-q": "pane::CloseActiveItem",
-      "tab": "pane::ActivateNextItem",
-      "shift-tab": "pane::ActivatePreviousItem",
-      "ctrl-h": "vim::ToggleProjectPanelFocus",
-      "ctrl-j": "workspace::ActivatePaneDown",
-      "ctrl-k": "workspace::ActivatePaneUp",
-      "ctrl-l": "workspace::ActivatePaneRight",
-      "shift-k": "editor::Hover",
-      "alt-j": "editor::MoveLineDown",
-      "alt-k": "editor::MoveLineUp",
-      "[ d": "editor::GoToPreviousDiagnostic",
-      "] d": "editor::GoToDiagnostic",
-      "g d": "editor::GoToDefinition",
-      "g i": "editor::GoToImplementation",
-      "g t": "editor::GoToTypeDefinition",
-      "g shift-d": "editor::GoToDeclaration",
-      "g shift-r": "editor::FindAllReferences"
-    }
-  },
-  {
-    "context": "ProjectPanel",
-    "bindings": {
-      "ctrl-h": "project_panel::ToggleFocus",
-      "ctrl-l": "project_panel::ToggleFocus",
-      "o": "project_panel::Open"
-    }
-  },
-  {
-    "context": "Editor && !menu && vim_mode == visual",
-    "bindings": {
-      "alt-j": "editor::MoveLineDown",
-      "alt-k": "editor::MoveLineUp",
-      "space c a": "editor::ToggleCodeActions",
-      "space g h": "vim::StartOfLine",
-      "space g l": "vim::EndOfLine",
-      "space s t": "editor::SortLinesCaseSensitive",
-      "space ~": "editor::ToggleCase"
-    }
-  },
-  {
-    "context": "Editor && !menu && vim_mode == normal",
-    "bindings": {
-      "space space": "tab_switcher::Toggle",
-      "space tab": "tab_switcher::Toggle",
-      "space /": "buffer_search::Deploy",
-      "space +": "vim::Increment",
-      "space -": "vim::Decrement",
-      "space b": "workspace::NewFile",
-      "space c a": "editor::ToggleCodeActions",
-      "space c f": "editor::Format",
-      "space d b": "editor::ToggleBreakpoint",
-      "space d c": "debugger::Continue",
-      "space d f": "editor::Hover",
-      "space d i": "debugger::StepInto",
-      "space d o": "debugger::StepOut",
-      "space d p": "debugger::Pause",
-      "space d r": "debugger::Rerun",
-      "space d shift-o": "debugger::StepOver",
-      "space d t": "debugger::Stop",
-      "space d u": "debug_panel::ToggleFocus",
-      "space e": "project_panel::ToggleFocus",
-      "space g b": "git::Branch",
-      "space g c f": "git::FileHistory",
-      "space g h": "vim::StartOfLine",
-      "space g l": "vim::EndOfLine",
-      "space g s": "git::Diff",
-      "space h": "pane::SplitHorizontal",
-      "space l g": "git_panel::ToggleFocus",
-      "space l w": "editor::ToggleSoftWrap",
-      "space m p": "editor::Format",
-      "space q": "diagnostics::Deploy",
-      "space q t": "pane::CloseOtherItems",
-      "space r n": "editor::Rename",
-      "space r s": "editor::RestartLanguageServer",
-      "space s /": "workspace::NewSearch",
-      "space s a": "workspace::SaveAll",
-      "space s b": "tab_switcher::Toggle",
-      "space s d": "diagnostics::Deploy",
-      "space s d s": "project_symbols::Toggle",
-      "space s f": "file_finder::Toggle",
-      "space s g": "workspace::NewSearch",
-      "space s n": "workspace::SaveWithoutFormat",
-      "space shift-d": "diagnostics::DeployCurrentFile",
-      "space t o": "terminal_panel::ToggleFocus",
-      "space t r": "task::Rerun",
-      "space t s": "zed::OpenTasks",
-      "space t t": "editor::SpawnNearestTask",
-      "space u d": "editor::ToggleInlineDiagnostics",
-      "space v": "pane::SplitVertical",
-      "space w h": "workspace::ActivatePaneLeft",
-      "space w j": "workspace::ActivatePaneDown",
-      "space w k": "workspace::ActivatePaneUp",
-      "space w l": "workspace::ActivatePaneRight",
-      "space w p": "workspace::ActivatePreviousPane",
-      "space x": "pane::CloseActiveItem"
-    }
-  }
-]
diff --git a/.config/zed/prompts/prompts-library-db.0.mdb/data.mdb b/.config/zed/prompts/prompts-library-db.0.mdb/data.mdb
deleted file mode 100644
index edb1be9..0000000
Binary files a/.config/zed/prompts/prompts-library-db.0.mdb/data.mdb and /dev/null differ
diff --git a/.config/zed/prompts/prompts-library-db.0.mdb/lock.mdb b/.config/zed/prompts/prompts-library-db.0.mdb/lock.mdb
deleted file mode 100644
index 07156ca..0000000
Binary files a/.config/zed/prompts/prompts-library-db.0.mdb/lock.mdb and /dev/null differ
diff --git a/.config/zed/settings.json b/.config/zed/settings.json
deleted file mode 100644
index 49d4ae7..0000000
--- a/.config/zed/settings.json
+++ /dev/null
@@ -1,160 +0,0 @@
-// Zed settings
-//
-// For information on how to configure Zed, see the Zed
-// documentation: https://zed.dev/docs/configuring-zed
-//
-// This translates the main Neovim behaviors from `.config/n into
-// the Zed features that have direct equivalents.
-{
-    "telemetry": {
-        "diagnostics": false,
-        "metrics": false,
-    },
-
-    "vim_mode": true,
-  "base_keymap": "JetBrains",
-
-    "auto_install_extensions": {
-        "html": true,
-        "angular": true,
-        "lua": true,
-        "sql": true,
-        "kanagawa-themes": true,
-    },
-
-    "icon_theme": {
-        "mode": "dark",
-        "light": "Zed (Default)",
-        "dark": "Zed (Default)",
-    },
-    "theme": {
-        "mode": "dark",
-        "light": "Kanagawa Lotus",
-        "dark": "New Darcula",
-    },
-
-    "ui_font_size": 16,
-    "buffer_font_size": 15,
-
-    "gutter": {
-        "line_numbers": true,
-        "breakpoints": true,
-        "folds": true,
-        "min_line_number_digits": 4,
-    },
-    "relative_line_numbers": "enabled",
-    "soft_wrap": "none",
-    "show_wrap_guides": false,
-    "tab_size": 4,
-    "hard_tabs": false,
-    "vertical_scroll_margin": 4,
-    "horizontal_scroll_margin": 8,
-    "use_smartcase_search": true,
-    "show_whitespaces": "selection",
-    "hover_popover_delay": 300,
-    "auto_signature_help": true,
-    "remove_trailing_whitespace_on_save": true,
-    "format_on_save": "on",
-
-    "diagnostics_max_severity": null,
-    "diagnostics": {
-        "inline": {
-            "enabled": false,
-        },
-    },
-    "inlay_hints": {
-        "enabled": true,
-        "show_type_hints": true,
-        "show_parameter_hints": true,
-        "show_other_hints": true,
-        "show_background": false,
-    },
-
-    "git": {
-        "git_gutter": "tracked_files",
-        "inline_blame": {
-            "enabled": false,
-        },
-    },
-
-    "tabs": {
-        "file_icons": true,
-        "git_status": true,
-        "show_close_button": "always",
-        "show_diagnostics": "all",
-    },
-    "project_panel": {
-        "default_width": 320,
-        "git_status": true,
-        "show_diagnostics": "all",
-        "hide_hidden": false,
-        "auto_reveal_entries": true,
-        "indent_guides": {
-            "show": "always",
-        },
-    },
-    "toolbar": {
-        "breadcrumbs": true,
-        "quick_actions": true,
-        "selections_menu": true,
-        "code_actions": true,
-    },
-
-    "file_types": {
-        "Groovy": ["**/*.pipeline", "**/*.multibranch"],
-        "Terraform": ["**/*.tfvars"],
-    },
-
-    "languages": {
-        "JavaScript": {
-            "language_servers": ["typescript-language-server", "!vtsls", "..."],
-        },
-        "TypeScript": {
-            "language_servers": ["typescript-language-server", "!vtsls", "..."],
-        },
-        "TSX": {
-            "language_servers": ["typescript-language-server", "!vtsls", "..."],
-        },
-        "Lua": {
-            "formatter": {
-                "external": {
-                    "command": "stylua",
-                    "arguments": [
-                        "--respect-ignores",
-                        "--stdin-filepath",
-                        "{buffer_path}",
-                        "-",
-                    ],
-                },
-            },
-        },
-        "Python": {
-            "formatter": {
-                "external": {
-                    "command": "ruff",
-                    "arguments": [
-                        "format",
-                        "--stdin-filename",
-                        "{buffer_path}",
-                        "-",
-                    ],
-                },
-            },
-        },
-        "Shell Script": {
-            "tab_size": 4,
-            "hard_tabs": false,
-            "formatter": {
-                "external": {
-                    "command": "shfmt",
-                    "arguments": [
-                        "--filename",
-                        "{buffer_path}",
-                        "--indent",
-                        "4",
-                    ],
-                },
-            },
-        },
-    },
-}
diff --git a/.gitconfig b/.gitconfig
index 95b5cc7..361befc 100644
--- a/.gitconfig
+++ b/.gitconfig
@@ -27,13 +27,13 @@ today = !git all --since='12am'
 pom = push origin main
 pos = push origin staging
 pod = push origin develop
- pou = push origin uat
+pou = push origin uat
 ruo = remote update origin
 cma = commit --amend
 cmna = commit -n --amend
 del = branch -D
 cm = commit -m
-pf = push -f origin
+pf = push --force-with-lease origin
 po = push origin
 rv = remote -v
 rao = remote add origin
@@ -48,7 +48,7 @@ latest-tag = tag -l --sort=-version:refname
 back = !f() { git reset --soft HEAD~$1; }; f
 
 [push]
-default = matching
+default = simple
 
 [core]
 editor=nvim
diff --git a/.github/workflows/validate.yml b/.github/workflows/validate.yml
new file mode 100644
index 0000000..11bf146
--- /dev/null
+++ b/.github/workflows/validate.yml
@@ -0,0 +1,30 @@
+name: Validate
+
+on:
+  push:
+  pull_request:
+
+jobs:
+  dotfiles:
+    runs-on: ubuntu-24.04
+
+    steps:
+      - uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4
+
+      - name: Install validation tools
+        run: |
+          sudo apt-get update
+          sudo apt-get install --yes gnupg shellcheck shfmt zsh
+          source install/lib/common.sh
+          source install/lib/packages.sh
+          install_wezterm
+          brew install neovim starship stylua
+
+      - name: Restore Neovim plugins
+        env:
+          DOTFILES_CI: "1"
+          XDG_CONFIG_HOME: ${{ github.workspace }}/.config
+        run: nvim --headless "+Lazy! restore" +qa
+
+      - name: Validate
+        run: bin/check-dotfiles
diff --git a/.gitignore b/.gitignore
index d60bc0f..7c28fef 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,56 +1,33 @@
-# Created by https://www.toptal.com/developers/gitignore/api/vim
-# Edit at https://www.toptal.com/developers/gitignore?templates=vim
-
-### Vim ###
-# Swap
+# Vim
 [._]*.s[a-v][a-z]
-!*.svg  # comment out if you don't need vector files
 [._]*.sw[a-p]
 [._]s[a-rt-v][a-z]
 [._]ss[a-gi-z]
 [._]sw[a-p]
-
-# Session
 Session.vim
 Sessionx.vim
-
-# Temporary
 .netrwhist
 *~
-# Auto-generated tag files
 tags
-# Persistent undo
 [._]*.un~
+.nvimlog
+nvim.log
+.config/zed/
 
+# Track only the managed application configurations.
 .config/*
-
 !.config/nvim/
 !.config/lazygit/
 !.config/starship/
 !.config/wezterm/
-# machine-local, generated by .zshrc
 .config/wezterm/env.lua
-!.config/zed/
-!.config/zed/settings.json
-!.config/zed/keymap.json
 !.config/tmux/
-!.config/tmux/nord-theme.conf
-!.config/tmux/dragon-theme.conf
-!.config/tmux/wave-theme.conf
-!.config/tmux/tmux-cheatsheet.md
-!.config/tmux/tmux.conf
-!.config/.vimrc
 !.config/.ideavimrc
 
-# Ignore subfolders in tmux
+# Ignore generated or downloaded tmux content.
 .config/tmux/**
-!.config/tmux/nord-theme.conf
+.config/tmux/current-theme.conf
 !.config/tmux/dragon-theme.conf
 !.config/tmux/wave-theme.conf
 !.config/tmux/tmux-cheatsheet.md
 !.config/tmux/tmux.conf
-!.config/.vimrc
-!.config/.ideavimrc
-
-.nvimlog
-# End of https://www.toptal.com/developers/gitignore/api/vim
diff --git a/.tmux.conf b/.tmux.conf
deleted file mode 100644
index 30c568b..0000000
--- a/.tmux.conf
+++ /dev/null
@@ -1 +0,0 @@
-source-file ~/.config/tmux/tmux.conf
diff --git a/.zshrc b/.zshrc
index 38068bb..f34b3e2 100644
--- a/.zshrc
+++ b/.zshrc
@@ -3,13 +3,13 @@
 if [ -x /home/linuxbrew/.linuxbrew/bin/brew ]; then
   eval "$(/home/linuxbrew/.linuxbrew/bin/brew shellenv)"
 fi
+export PATH="$HOME/.local/bin:$PATH"
 
 # ===================== User-tunable environment ========================
-# Single place to control the look of the whole stack. Everything below
-# (and the wezterm env.lua writer further down) derives from these.
+# Single place to control the look of the whole stack.
 export KANAGAWA_THEME="wave"            # wave | dragon
 export WEZTERM_FONT_SIZE="13"
-export WEZTERM_WINDOW_OPACITY="0.80"
+export WEZTERM_WINDOW_OPACITY="0.9"
 export WEZTERM_TEXT_OPACITY="1.0"
 # ========================================================================
 
@@ -31,32 +31,11 @@ case "${KANAGAWA_THEME}" in
     ;;
 esac
 
-# Write a deterministic tmux theme selector file so tmux servers don't depend
-# on inherited shell env vars.
-export TMUX_THEME_FILE="$HOME/.config/tmux/current-theme.conf"
-mkdir -p "$HOME/.config/tmux"
-if [ "$TMUX_THEME" = "wave" ]; then
-  printf 'source-file %s\n' "$HOME/.config/tmux/wave-theme.conf" >| "$TMUX_THEME_FILE"
-else
-  printf 'source-file %s\n' "$HOME/.config/tmux/dragon-theme.conf" >| "$TMUX_THEME_FILE"
+# Generate the theme files consumed by GUI-launched WezTerm and tmux.
+if command -v dotfiles-apply-theme >/dev/null 2>&1; then
+  dotfiles-apply-theme
 fi
 
-# Write WezTerm settings file (same pattern as tmux above). GUI-launched
-# WezTerm never sees shell exports, so it watches this file and live-reloads
-# when the values change.
-_wez_env_file="$HOME/.config/wezterm/env.lua"
-_wez_env_content="return {
-  theme = \"$WEZTERM_THEME\",
-  font_size = $WEZTERM_FONT_SIZE,
-  window_opacity = $WEZTERM_WINDOW_OPACITY,
-  text_opacity = $WEZTERM_TEXT_OPACITY,
-}"
-mkdir -p "$HOME/.config/wezterm"
-if [ ! -f "$_wez_env_file" ] || [ "$(cat "$_wez_env_file")" != "$_wez_env_content" ]; then
-  printf '%s\n' "$_wez_env_content" >| "$_wez_env_file"
-fi
-unset _wez_env_file _wez_env_content
-
 # Starship
 if command -v starship >/dev/null 2>&1; then
   eval "$(starship init zsh)"
@@ -81,6 +60,9 @@ ZSH_HIGHLIGHT_STYLES[path]=none
 ZSH_HIGHLIGHT_STYLES[path_prefix]=none
 
 # Autosuggestions
+# The plugin default is intentionally dim and becomes unreadable with a
+# transparent terminal background.
+ZSH_AUTOSUGGEST_HIGHLIGHT_STYLE='fg=#938aa9'
 for _p in \
   "$HOMEBREW_PREFIX/share/zsh-autosuggestions/zsh-autosuggestions.zsh" \
   /usr/share/zsh-autosuggestions/zsh-autosuggestions.zsh
@@ -124,7 +106,12 @@ alias sudo="sudo "
 alias lg="lazygit"
 alias update="brew upgrade && sudo apt update && sudo apt upgrade -y"
 
-if command -v tmux &>/dev/null && [ -z "$TMUX" ]; then
+export DOTFILES_AUTO_TMUX="${DOTFILES_AUTO_TMUX:-0}"
+if [ "$DOTFILES_AUTO_TMUX" = "1" ] \
+  && command -v tmux &>/dev/null \
+  && [ -z "$TMUX" ] \
+  && [ -z "$SSH_CONNECTION" ]
+then
   tmux attach -t default 2>/dev/null || tmux new -s default
 fi
 
diff --git a/README.md b/README.md
index 3a66efa..41a4eb2 100644
--- a/README.md
+++ b/README.md
@@ -5,21 +5,12 @@ Linux dotfiles oriented around **Pop!_OS 24.04** (Cosmic DE).
 ## Quick Setup
 
 ```bash
-# Clone
-git clone <repo-url> ~/dotfiles
-
-# Symlink configs
-ln -sfn ~/dotfiles/.config/nvim ~/.config/nvim
-ln -sfn ~/dotfiles/.config/tmux ~/.config/tmux
-ln -sfn ~/dotfiles/.config/starship ~/.config/starship
-ln -sfn ~/dotfiles/.config/lazygit ~/.config/lazygit
-ln -sfn ~/dotfiles/.config/wezterm ~/.config/wezterm
-ln -sfn ~/dotfiles/.config/zed ~/.config/zed
-ln -sfn ~/dotfiles/.config/.ideavimrc ~/.ideavimrc
-ln -sfn ~/dotfiles/.zshrc ~/.zshrc
-ln -sfn ~/dotfiles/.gitconfig ~/.gitconfig
+git clone https://github.com/brianpooe/dotfiles.git ~/dotfiles
+~/dotfiles/install/install.sh --dotfiles-only
 ```
 
+The installer backs up existing targets before linking replacements.
+
 ## Install
 
 On Pop!_OS / Ubuntu 24.04, run the bundled installer. It uses **apt** for
@@ -33,7 +24,8 @@ starship, gh, zsh plugins) so those tools stay current — one
 ```
 
 See [`install/README.md`](install/README.md) for flags and the full
-package list. The `update` alias runs `brew upgrade && sudo apt upgrade`.
+package list. The `update` alias runs
+`brew upgrade && sudo apt update && sudo apt upgrade -y`.
 
 ## Theme
 
@@ -44,3 +36,20 @@ Set in shell:
 ```bash
 export KANAGAWA_THEME="wave"  # or "dragon"
 ```
+
+Opening a new shell runs `dotfiles-apply-theme`, which writes the generated
+tmux and WezTerm settings to `~/.cache/dotfiles`.
+
+Automatic tmux startup is opt-in:
+
+```bash
+export DOTFILES_AUTO_TMUX=1
+```
+
+## Validate
+
+```bash
+bin/check-dotfiles
+```
+
+The same checks run in GitHub Actions.
diff --git a/bin/check-dotfiles b/bin/check-dotfiles
new file mode 100755
index 0000000..f879470
--- /dev/null
+++ b/bin/check-dotfiles
@@ -0,0 +1,60 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+repo_root="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+cd "$repo_root"
+
+export PATH="$HOME/.local/share/nvim/mason/bin:$PATH"
+
+require_cmd() {
+  command -v "$1" >/dev/null 2>&1 || {
+    printf 'Required validation tool not found: %s\n' "$1" >&2
+    exit 1
+  }
+}
+
+for command in bash git nvim shellcheck shfmt starship stylua wezterm zsh; do
+  require_cmd "$command"
+done
+
+shell_files=(bin/dotfiles-apply-theme bin/check-dotfiles install/install.sh install/lib/*.sh)
+
+git diff --check
+bash -n "${shell_files[@]}"
+zsh -n .zshrc
+git config --file .gitconfig --list >/dev/null
+shellcheck --exclude=SC1091 "${shell_files[@]}"
+shfmt -d -i 2 -ci "${shell_files[@]}"
+stylua --check .config/nvim
+
+tmp="$(mktemp -d)"
+trap 'rm -rf "$tmp"' EXIT
+mkdir -p "$tmp/data/nvim"
+ln -s "$HOME/.local/share/nvim/lazy" "$tmp/data/nvim/lazy"
+
+HOME="$tmp/home" \
+  KANAGAWA_THEME=wave \
+  WEZTERM_FONT_SIZE=13 \
+  WEZTERM_WINDOW_OPACITY=.9 \
+  WEZTERM_TEXT_OPACITY=1 \
+  bin/dotfiles-apply-theme
+
+STARSHIP_CONFIG="$repo_root/.config/starship/starship.toml" starship print-config >/dev/null
+STARSHIP_CONFIG="$repo_root/.config/starship/starship-wave.toml" starship print-config >/dev/null
+wezterm --config-file "$repo_root/.config/wezterm/wezterm.lua" show-keys --lua >/dev/null
+
+nvim_output="$(
+  DOTFILES_CI=1 \
+    XDG_CONFIG_HOME="$repo_root/.config" \
+    XDG_CACHE_HOME="$tmp/cache" \
+    XDG_DATA_HOME="$tmp/data" \
+    XDG_STATE_HOME="$tmp/state" \
+    nvim --headless '+sleep 100m' '+lua assert(vim.v.errmsg == "", vim.v.errmsg)' '+qa' 2>&1
+)"
+if [[ -n $nvim_output ]]; then
+  printf 'Neovim startup produced unexpected output:\n%s\n' "$nvim_output" >&2
+  exit 1
+fi
+
+printf 'All dotfile checks passed.\n'
diff --git a/bin/dotfiles-apply-theme b/bin/dotfiles-apply-theme
new file mode 100755
index 0000000..137e4df
--- /dev/null
+++ b/bin/dotfiles-apply-theme
@@ -0,0 +1,46 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+theme="${KANAGAWA_THEME:-wave}"
+font_size="${WEZTERM_FONT_SIZE:-13}"
+window_opacity="${WEZTERM_WINDOW_OPACITY:-0.9}"
+text_opacity="${WEZTERM_TEXT_OPACITY:-1.0}"
+state_dir="$HOME/.cache/dotfiles"
+
+case "$theme" in
+  wave | kanagawa-wave) theme=wave ;;
+  dragon | kanagawa-dragon) theme=dragon ;;
+  *) theme=dragon ;;
+esac
+
+for value in "$font_size" "$window_opacity" "$text_opacity"; do
+  [[ $value =~ ^([0-9]+([.][0-9]*)?|[.][0-9]+)$ ]] || {
+    printf 'Invalid numeric theme value: %s\n' "$value" >&2
+    exit 1
+  }
+done
+
+mkdir -p "$state_dir"
+
+write_if_changed() {
+  local destination="$1" content="$2" temporary
+
+  if [[ -f $destination ]] && [[ $(<"$destination") == "$content" ]]; then
+    return
+  fi
+
+  temporary="$(mktemp "$state_dir/.theme.XXXXXX")"
+  printf '%s\n' "$content" >"$temporary"
+  mv "$temporary" "$destination"
+}
+
+write_if_changed "$state_dir/tmux-theme.conf" \
+  "source-file \"$HOME/.config/tmux/$theme-theme.conf\""
+
+write_if_changed "$state_dir/wezterm-env.lua" "return {
+  theme = \"$theme\",
+  font_size = $font_size,
+  window_opacity = $window_opacity,
+  text_opacity = $text_opacity,
+}"
diff --git a/install/README.md b/install/README.md
index b2b1bec..d1bd893 100644
--- a/install/README.md
+++ b/install/README.md
@@ -12,6 +12,10 @@ Ubuntu 24.04 / Debian-derivative) to the state these dotfiles assume.
 | **nvm** | Node.js runtime | Installs the latest LTS release and sets it as the default; `.zshrc` sources `~/.nvm/nvm.sh`. |
 | **tpm** | tmux plugin manager | Clone of `tmux-plugins/tpm` so the bundled `tmux.conf` works on first launch. |
 
+Downloaded installer scripts, apt signing keys, and the Nerd Font archive
+are pinned and verified before use. Updating their upstream versions requires
+updating the corresponding SHA-256 hashes or fingerprints in `install/lib/`.
+
 GitHub-release-binary downloads (the previous approach for nvim/lazygit/
 starship) have been retired — they ran latest at install time then went
 stale. Brew solves that.
@@ -46,7 +50,7 @@ install/install.sh --help
 ## Keeping current
 
 ```bash
-update                  # alias: brew upgrade && sudo apt upgrade
+update                  # alias: brew upgrade && sudo apt update && sudo apt upgrade -y
 ```
 
 The CLI tools come from brew, so they stay on bleeding-edge stable. Brave
@@ -63,6 +67,7 @@ install/
   lib/packages.sh      apt base + WezTerm + Brave Beta vendor repos
   lib/brew.sh          install Homebrew + `brew bundle`
   lib/extras.sh        nvm + tpm
+  lib/fonts.sh         verified JetBrainsMono Nerd Font install
   lib/dotfiles.sh      symlink dotfiles + chsh zsh
 ```
 
@@ -75,8 +80,9 @@ install/
 5. **Homebrew install** (NONINTERACTIVE) + `brew bundle` against `Brewfile`.
 6. **nvm** (pinned `$NVM_VERSION`, default `v0.40.1`) + latest LTS Node.js.
 7. **tpm** clone to `~/.tmux/plugins/tpm`.
-8. **Symlink** `nvim tmux starship lazygit wezterm zed → ~/.config/...`;
-   `.config/.ideavimrc → ~/.ideavimrc`; `.zshrc`, `.gitconfig → ~`.
+8. **Symlink** `nvim tmux starship lazygit wezterm → ~/.config/...`;
+   `.config/.ideavimrc → ~/.ideavimrc`; `.zshrc`, `.gitconfig → ~`;
+   `dotfiles-apply-theme → ~/.local/bin/`.
 9. **chsh** login shell to zsh.
 
 Pre-existing config targets get backed up to `*.pre-install.<timestamp>`,
diff --git a/install/install.sh b/install/install.sh
index 601144a..b833f06 100755
--- a/install/install.sh
+++ b/install/install.sh
@@ -36,7 +36,10 @@ for arg in "$@"; do
   case $arg in
     --packages-only) MODE=packages ;;
     --dotfiles-only) MODE=dotfiles ;;
-    -h|--help) usage; exit 0 ;;
+    -h | --help)
+      usage
+      exit 0
+      ;;
     *) die "Unknown argument: $arg (try --help)" ;;
   esac
 done
@@ -46,6 +49,7 @@ preflight() {
   ((EUID != 0)) || die "Do not run as root; run as your regular user."
   require_cmd sudo
   require_cmd curl
+  require_cmd sha256sum
 }
 
 main() {
@@ -76,7 +80,7 @@ main() {
 
   info "Done. Open a new shell (or log out + back in) to pick up the new login shell."
   info "First tmux launch: prefix + I to fetch tpm plugins."
-  info "Keep tools current with: brew upgrade && sudo apt upgrade"
+  info "Keep tools current with: brew upgrade && sudo apt update && sudo apt upgrade -y"
 }
 
 main
diff --git a/install/lib/brew.sh b/install/lib/brew.sh
index 9a4f6cf..e97b98c 100644
--- a/install/lib/brew.sh
+++ b/install/lib/brew.sh
@@ -3,14 +3,25 @@
 # Brew owns the CLI toolchain so `brew upgrade` always gets latest versions.
 
 BREW_PREFIX="/home/linuxbrew/.linuxbrew"
+HOMEBREW_INSTALL_COMMIT="93a25fd2d2fdb86422303c292b9223f84ef23eaf"
+HOMEBREW_INSTALL_SHA256="17f204b128869ec71e6b650051f1e65ef5b74cf994c2ff8b919103241554dd2f"
 
 install_homebrew() {
   if [[ -x $BREW_PREFIX/bin/brew ]]; then
     info "Homebrew already installed"
   else
     info "Installing Homebrew..."
-    NONINTERACTIVE=1 bash -c \
-      "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
+    local installer
+    installer="$(mktemp)"
+    download_verified \
+      "https://raw.githubusercontent.com/Homebrew/install/$HOMEBREW_INSTALL_COMMIT/install.sh" \
+      "$HOMEBREW_INSTALL_SHA256" \
+      "$installer"
+    if ! NONINTERACTIVE=1 bash "$installer"; then
+      rm -f "$installer"
+      die "Homebrew installer failed"
+    fi
+    rm -f "$installer"
   fi
   eval "$("$BREW_PREFIX/bin/brew" shellenv)"
 }
diff --git a/install/lib/common.sh b/install/lib/common.sh
index 259062f..e3dfb39 100644
--- a/install/lib/common.sh
+++ b/install/lib/common.sh
@@ -8,12 +8,49 @@ APT_LISTS_DIR="/etc/apt/sources.list.d"
 info() { printf '\033[0;32m==>\033[0m %s\n' "$*"; }
 warn() { printf '\033[1;33mWARNING:\033[0m %s\n' "$*" >&2; }
 error() { printf '\033[0;31mERROR:\033[0m %s\n' "$*" >&2; }
-die() { error "$*"; exit 1; }
+die() {
+  error "$*"
+  exit 1
+}
 
 require_cmd() {
   command -v "$1" >/dev/null 2>&1 || die "Required command not found: $1"
 }
 
+download_verified() {
+  local url="$1" sha256="$2" destination="$3"
+
+  if ! curl -fsSL --retry 3 "$url" -o "$destination"; then
+    rm -f "$destination"
+    die "Failed to download $url"
+  fi
+  if ! printf '%s  %s\n' "$sha256" "$destination" | sha256sum --check --status -; then
+    rm -f "$destination"
+    die "SHA-256 verification failed for $url"
+  fi
+}
+
+key_fingerprints_match() {
+  local key="$1" expected_fingerprints="$2"
+  local actual_fingerprints normalized_expected
+
+  actual_fingerprints="$(
+    gpg --show-keys --with-colons "$key" 2>/dev/null |
+      awk -F: '$1 == "fpr" { print $10 }' |
+      sort -u |
+      tr '\n' ' '
+  )"
+  normalized_expected="$(
+    for fingerprint in $expected_fingerprints; do
+      printf '%s\n' "$fingerprint"
+    done |
+      sort -u |
+      tr '\n' ' '
+  )"
+
+  [[ -n $actual_fingerprints && $actual_fingerprints == "$normalized_expected" ]]
+}
+
 apt_install() {
   sudo apt-get install -y --no-install-recommends "$@"
 }
@@ -45,15 +82,14 @@ backup_and_link() {
   info "Linked $dest -> $src"
 }
 
-# Add a signed apt repo. Args: name keyring_url repo_line
-# Downloads the key to a temp file first and verifies it, so a failed
-# fetch never leaves an empty keyring or partial list file behind.
+# Add a signed apt repo. Args: name keyring_url repo_line expected_fingerprints
 add_apt_repo() {
-  local name="$1" keyring_url="$2" repo_line="$3"
+  local name="$1" keyring_url="$2" repo_line="$3" expected_fingerprints="$4"
   local keyring="$KEYRINGS_DIR/$name.gpg"
   local list="$APT_LISTS_DIR/$name.list"
 
-  if [[ -f $list && -s $keyring ]]; then
+  if [[ -f $list && -s $keyring ]] &&
+    key_fingerprints_match "$keyring" "$expected_fingerprints"; then
     return 0
   fi
   info "Adding apt repo: $name"
@@ -68,7 +104,10 @@ add_apt_repo() {
   fi
   [[ -s $tmp_key ]] || die "Downloaded key for $name is empty"
 
-  if ! gpg --yes --dearmor -o "$tmp_gpg" < "$tmp_key" 2>/dev/null; then
+  key_fingerprints_match "$tmp_key" "$expected_fingerprints" ||
+    die "Signing-key fingerprint verification failed for $name"
+
+  if ! gpg --yes --dearmor -o "$tmp_gpg" <"$tmp_key" 2>/dev/null; then
     # Already binary (.gpg) keys can't be dearmored; use the raw bytes instead.
     cp "$tmp_key" "$tmp_gpg"
   fi
@@ -76,5 +115,5 @@ add_apt_repo() {
   sudo install -d -m 0755 "$KEYRINGS_DIR"
   sudo install -m 0644 "$tmp_gpg" "$keyring"
   echo "$repo_line" | sudo tee "$list" >/dev/null
-  unset _APT_UPDATED  # force re-update so the new repo is seen
+  unset _APT_UPDATED # force re-update so the new repo is seen
 }
diff --git a/install/lib/dotfiles.sh b/install/lib/dotfiles.sh
index 7d4d2e8..e8d245c 100644
--- a/install/lib/dotfiles.sh
+++ b/install/lib/dotfiles.sh
@@ -3,15 +3,15 @@
 
 link_dotfiles() {
   info "Linking dotfiles from $DOTFILES_DIR..."
-  backup_and_link "$DOTFILES_DIR/.config/nvim"      "$HOME/.config/nvim"
-  backup_and_link "$DOTFILES_DIR/.config/tmux"      "$HOME/.config/tmux"
-  backup_and_link "$DOTFILES_DIR/.config/starship"  "$HOME/.config/starship"
-  backup_and_link "$DOTFILES_DIR/.config/lazygit"   "$HOME/.config/lazygit"
-  backup_and_link "$DOTFILES_DIR/.config/wezterm"   "$HOME/.config/wezterm"
-  backup_and_link "$DOTFILES_DIR/.config/zed"       "$HOME/.config/zed"
+  backup_and_link "$DOTFILES_DIR/.config/nvim" "$HOME/.config/nvim"
+  backup_and_link "$DOTFILES_DIR/.config/tmux" "$HOME/.config/tmux"
+  backup_and_link "$DOTFILES_DIR/.config/starship" "$HOME/.config/starship"
+  backup_and_link "$DOTFILES_DIR/.config/lazygit" "$HOME/.config/lazygit"
+  backup_and_link "$DOTFILES_DIR/.config/wezterm" "$HOME/.config/wezterm"
   backup_and_link "$DOTFILES_DIR/.config/.ideavimrc" "$HOME/.ideavimrc"
-  backup_and_link "$DOTFILES_DIR/.zshrc"            "$HOME/.zshrc"
-  backup_and_link "$DOTFILES_DIR/.gitconfig"        "$HOME/.gitconfig"
+  backup_and_link "$DOTFILES_DIR/.zshrc" "$HOME/.zshrc"
+  backup_and_link "$DOTFILES_DIR/.gitconfig" "$HOME/.gitconfig"
+  backup_and_link "$DOTFILES_DIR/bin/dotfiles-apply-theme" "$HOME/.local/bin/dotfiles-apply-theme"
 }
 
 set_zsh_as_shell() {
diff --git a/install/lib/extras.sh b/install/lib/extras.sh
index 179d4a8..64703a0 100644
--- a/install/lib/extras.sh
+++ b/install/lib/extras.sh
@@ -2,15 +2,22 @@
 # Per-user helpers not managed by brew: nvm (official installer) + tpm.
 
 NVM_VERSION="${NVM_VERSION:-v0.40.1}"
+NVM_INSTALL_SHA256="${NVM_INSTALL_SHA256:-abdb525ee9f5b48b34d8ed9fc67c6013fb0f659712e401ecd88ab989b3af8f53}"
 
 install_nvm() {
   if [[ -s $HOME/.nvm/nvm.sh ]]; then
     info "nvm already installed"
   else
     info "Installing nvm ($NVM_VERSION)..."
-    PROFILE=/dev/null bash -c \
-      "curl -fsSL https://raw.githubusercontent.com/nvm-sh/nvm/$NVM_VERSION/install.sh | bash" ||
+    local installer
+    installer="$(mktemp)"
+    download_verified \
+      "https://raw.githubusercontent.com/nvm-sh/nvm/$NVM_VERSION/install.sh" \
+      "$NVM_INSTALL_SHA256" \
+      "$installer"
+    PROFILE=/dev/null bash "$installer" ||
       warn "nvm install failed (install manually if you need Node)"
+    rm -f "$installer"
   fi
 
   if [[ -s $HOME/.nvm/nvm.sh ]]; then
diff --git a/install/lib/fonts.sh b/install/lib/fonts.sh
index 53baefa..ae183c7 100644
--- a/install/lib/fonts.sh
+++ b/install/lib/fonts.sh
@@ -6,6 +6,8 @@
 
 NERD_FONT_NAME="JetBrainsMono"
 NERD_FONT_DIR="$HOME/.local/share/fonts/${NERD_FONT_NAME}NerdFont"
+NERD_FONT_VERSION="v3.4.0"
+NERD_FONT_SHA256="ef552a3e638f25125c6ad4c51176a6adcdce295ab1d2ffacf0db060caf8c1582"
 
 install_nerd_font() {
   if fc-list 2>/dev/null | grep -qi "JetBrainsMono Nerd Font"; then
@@ -14,15 +16,12 @@ install_nerd_font() {
   fi
 
   info "Installing ${NERD_FONT_NAME} Nerd Font..."
-  local url="https://github.com/ryanoasis/nerd-fonts/releases/latest/download/${NERD_FONT_NAME}.tar.xz"
+  local url="https://github.com/ryanoasis/nerd-fonts/releases/download/$NERD_FONT_VERSION/${NERD_FONT_NAME}.tar.xz"
   local tmp
   tmp="$(mktemp -d)"
   trap 'rm -rf "$tmp"' RETURN
 
-  if ! curl -fsSL --retry 3 -o "$tmp/font.tar.xz" "$url"; then
-    warn "Nerd Font download failed; install manually from https://www.nerdfonts.com"
-    return
-  fi
+  download_verified "$url" "$NERD_FONT_SHA256" "$tmp/font.tar.xz"
 
   mkdir -p "$NERD_FONT_DIR"
   tar -xJf "$tmp/font.tar.xz" -C "$NERD_FONT_DIR"
diff --git a/install/lib/packages.sh b/install/lib/packages.sh
index 9b11790..f56125f 100644
--- a/install/lib/packages.sh
+++ b/install/lib/packages.sh
@@ -44,7 +44,8 @@ install_wezterm() {
   fi
   add_apt_repo wezterm-fury \
     https://apt.fury.io/wez/gpg.key \
-    "deb [signed-by=$KEYRINGS_DIR/wezterm-fury.gpg] https://apt.fury.io/wez/ * *"
+    "deb [signed-by=$KEYRINGS_DIR/wezterm-fury.gpg] https://apt.fury.io/wez/ * *" \
+    "0CA603116C960BAFB2BF310BD7BA31CF90C4B319 82FA179A44D70EEF9CDEB52659C703F427E1A6C9"
   apt_update_once
   apt_install wezterm
 }
@@ -59,7 +60,8 @@ install_brave_beta() {
   # "beta" in the name.
   add_apt_repo brave-browser-beta \
     https://brave-browser-apt-beta.s3.brave.com/brave-browser-beta-archive-keyring.gpg \
-    "deb [signed-by=$KEYRINGS_DIR/brave-browser-beta.gpg arch=amd64] https://brave-browser-apt-beta.s3.brave.com/ stable main"
+    "deb [signed-by=$KEYRINGS_DIR/brave-browser-beta.gpg arch=amd64] https://brave-browser-apt-beta.s3.brave.com/ stable main" \
+    "56F49901AB19BAF099A95A76C3DE1DD4F661CDCB 8C1F16AB24DF8F75C1CF56595929A141E0E87F1F B721E073B7EF8E56ACC6B23ECBC67D2399225CCF"
   apt_update_once
   apt_install brave-browser-beta
 }