diff --git a/lazy-lock.json b/lazy-lock.json
deleted file mode 100644
index f403e7c..0000000
--- a/lazy-lock.json
+++ /dev/null
@@ -1,28 +0,0 @@
-{
-  "LuaSnip": { "branch": "master", "commit": "642b0c595e11608b4c18219e93b88d7637af27bc" },
-  "autoclose.nvim": { "branch": "main", "commit": "bafd0368716216fa6a7bb2a43ecd889b44efdb46" },
-  "base16-vim": { "branch": "master", "commit": "3be3cd82cd31acfcab9a41bad853d9c68d30478d" },
-  "bitcoin-script-hints.nvim": { "branch": "main", "commit": "628badbb09a230e3838d863b21dcc07cdd2429bc" },
-  "bufferline.nvim": { "branch": "main", "commit": "655133c3b4c3e5e05ec549b9f8cc2894ac6f51b3" },
-  "cmp-nvim-lsp": { "branch": "main", "commit": "cbc7b02bb99fae35cb42f514762b89b5126651ef" },
-  "cmp_luasnip": { "branch": "master", "commit": "98d9cb5c2c38532bd9bdb481067b20fea8f32e90" },
-  "gitsigns.nvim": { "branch": "main", "commit": "6d808f99bd63303646794406e270bd553ad7792e" },
-  "indent-blankline.nvim": { "branch": "master", "commit": "d28a3f70721c79e3c5f6693057ae929f3d9c0a03" },
-  "lazy.nvim": { "branch": "main", "commit": "306a05526ada86a7b30af95c5cc81ffba93fef97" },
-  "log-highlight.nvim": { "branch": "main", "commit": "ca88628f6dd3b9bb46f9a7401669e24cf7de47a4" },
-  "lualine.nvim": { "branch": "master", "commit": "131a558e13f9f28b15cd235557150ccb23f89286" },
-  "mason-lspconfig.nvim": { "branch": "main", "commit": "0c2823e0418f3d9230ff8b201c976e84de1cb401" },
-  "mason.nvim": { "branch": "main", "commit": "cb8445f8ce85d957416c106b780efd51c6298f89" },
-  "neo-tree.nvim": { "branch": "main", "commit": "19d20a99bf0061a5ecc4343d2f09fa713306c965" },
-  "nui.nvim": { "branch": "main", "commit": "de740991c12411b663994b2860f1a4fd0937c130" },
-  "nvim-cmp": { "branch": "main", "commit": "a1d504892f2bc56c2e79b65c6faded2fd21f3eca" },
-  "nvim-lspconfig": { "branch": "master", "commit": "f7e89f3d19fb436e1fbeff3bf4291eef35da94e3" },
-  "nvim-navic": { "branch": "master", "commit": "f5eba192f39b453675d115351808bd51276d9de5" },
-  "nvim-treesitter": { "branch": "main", "commit": "df7489eeea351bece7fd0f9c825be5cb6a1438f0" },
-  "nvim-web-devicons": { "branch": "master", "commit": "4fc505ac7bd7692824a142e96e5f529c133862f8" },
-  "plenary.nvim": { "branch": "master", "commit": "74b06c6c75e4eeb3108ec01852001636d85a932b" },
-  "telescope.nvim": { "branch": "0.1.x", "commit": "a0bbec21143c7bc5f8bb02e0005fa0b982edc026" },
-  "todo-comments.nvim": { "branch": "main", "commit": "31e3c38ce9b29781e4422fc0322eb0a21f4e8668" },
-  "treesitter-parser-registry": { "branch": "main", "commit": "6eb15358bb9fc88f0d3401d8538d56652e9bdf3c" },
-  "which-key.nvim": { "branch": "main", "commit": "3aab2147e74890957785941f0c1ad87d0a44c15a" }
-}
diff --git a/lua/plugins/disabled.lua b/lua/plugins/disabled.lua
index 0b7a483..64e75ec 100644
--- a/lua/plugins/disabled.lua
+++ b/lua/plugins/disabled.lua
@@ -1,3 +1,5 @@
 return {
+	{ "williamboman/mason.nvim", enabled = false },
+	{ "williamboman/mason-lspconfig.nvim", enabled = false },
 	{ "jay-babu/mason-nvim-dap.nvim", enabled = false },
 }
diff --git a/lua/plugins/lsp.lua b/lua/plugins/lsp.lua
index 3372cff..c31339b 100644
--- a/lua/plugins/lsp.lua
+++ b/lua/plugins/lsp.lua
@@ -1,7 +1,11 @@
 -- Neovim 0.11+ LSP configuration
 -- Uses nvim-lspconfig for server definitions + vim.lsp.enable() API
 
--- Servers to ensure are installed via Mason.
+-- Detect NixOS (Mason doesn't work on NixOS due to FHS issues)
+local is_nixos = vim.fn.filereadable("/etc/NIXOS") == 1
+
+-- Servers to ensure are installed via Mason (non-NixOS only)
+-- On NixOS, install these via extraPackages or per-project devShells
 local mason_ensure_installed = {
   "lua_ls",       -- Neovim config
   "nil_ls",       -- Nix (nixd not available in Mason)
@@ -14,43 +18,13 @@ local mason_ensure_installed = {
   "yamlls",       -- YAML
 }
 
-local treesitter_parsers = {
-  "lua",
-  "c",
-  "cpp",
-  "python",
-  "nix",
-  "rust",
-  "bash",
-  "markdown",
-  "html",
-  "html_tags",
-  "javascript",
-  "ecma",
-  "jsx",
-  "css",
-  "vim",
-  "git_config",
-  "git_rebase",
-  "gitattributes",
-  "gitcommit",
-  "gitignore",
-}
-
 return {
   {
-    "neovim-treesitter/nvim-treesitter",
-    name = "nvim-treesitter",
-    dependencies = {
-      "neovim-treesitter/treesitter-parser-registry",
-      "williamboman/mason.nvim",
-    },
-    lazy = false,
+    "nvim-treesitter/nvim-treesitter",
     build = ":TSUpdate",
-    init = function()
-      vim.api.nvim_create_autocmd("FileType", {
-        group = vim.api.nvim_create_augroup("config_treesitter", { clear = true }),
-        pattern = {
+    config = function()
+      require('nvim-treesitter.configs').setup({
+        ensure_installed = {
           "lua",
           "c",
           "cpp",
@@ -61,133 +35,22 @@ return {
           "markdown",
           "html",
           "javascript",
-          "javascriptreact",
           "css",
+
           "vim",
-          "gitconfig",
-          "gitrebase",
+
+          "git_config",
+          "git_rebase",
           "gitattributes",
           "gitcommit",
-          "gitignore",
+          "gitignore"
         },
-        callback = function(event)
-          if pcall(vim.treesitter.start, event.buf) then
-            vim.bo[event.buf].indentexpr = "v:lua.require'nvim-treesitter'.indentexpr()"
-          end
-        end,
+        auto_install = true,
+        sync_install = true,
+        highlight = {
+          enable = true,
+        }
       })
-    end,
-    config = function()
-      require("nvim-treesitter").setup()
-
-      local function has_c_compiler()
-        return vim.fn.executable("cc") == 1
-          or vim.fn.executable("gcc") == 1
-          or vim.fn.executable("clang") == 1
-      end
-
-      local function install_missing_parsers(missing)
-        if not has_c_compiler() then
-          vim.notify_once(
-            "A C compiler is required to install or update Treesitter parsers",
-            vim.log.levels.WARN
-          )
-          return
-        end
-
-        require("nvim-treesitter").install(missing)
-      end
-
-      local function tree_sitter_cli_works()
-        if vim.fn.executable("tree-sitter") == 0 then
-          return false
-        end
-
-        local result = vim.system({ "tree-sitter", "--version" }, { text = true }):wait()
-        if result.code == 0 then
-          return true
-        end
-
-        vim.notify_once(
-          "tree-sitter CLI is installed but cannot run. On NixOS, enable nix-ld so Mason-installed binaries can execute.",
-          vim.log.levels.WARN
-        )
-        return false
-      end
-
-      local function ensure_treesitter_cli(callback)
-        if tree_sitter_cli_works() then
-          callback()
-          return
-        end
-
-        if #vim.api.nvim_list_uis() == 0 then
-          return
-        end
-
-        local mason_ok, mason = pcall(require, "mason")
-        local registry_ok, registry = pcall(require, "mason-registry")
-        if not mason_ok or not registry_ok then
-          vim.notify_once(
-            "tree-sitter CLI is required to install or update parsers; install tree-sitter-cli or enable mason.nvim",
-            vim.log.levels.WARN
-          )
-          return
-        end
-
-        mason.setup()
-        registry.refresh(function()
-          local package_ok, package = pcall(registry.get_package, "tree-sitter-cli")
-          if not package_ok then
-            vim.notify_once(
-              "Mason registry does not include tree-sitter-cli; install tree-sitter-cli before running :TSUpdate",
-              vim.log.levels.WARN
-            )
-            return
-          end
-
-          if package:is_installed() then
-            if tree_sitter_cli_works() then
-              callback()
-            end
-            return
-          end
-
-          if package:is_installing() then
-            vim.notify_once("tree-sitter-cli is already being installed by Mason", vim.log.levels.INFO)
-            return
-          end
-
-          vim.notify_once("Installing tree-sitter-cli with Mason for Treesitter parser updates", vim.log.levels.INFO)
-          package:install({}, function(success, error)
-            if success and tree_sitter_cli_works() then
-              callback()
-            else
-              vim.notify(
-                "Failed to install tree-sitter-cli with Mason: " .. tostring(error),
-                vim.log.levels.WARN
-              )
-            end
-          end)
-        end)
-      end
-
-      local installed = require("nvim-treesitter.config").get_installed()
-      local missing = vim.iter(treesitter_parsers)
-          :filter(function(parser)
-            return not vim.tbl_contains(installed, parser)
-          end)
-          :totable()
-
-      if #missing == 0 and #vim.api.nvim_list_uis() == 0 then
-        return
-      end
-
-      ensure_treesitter_cli(function()
-        if #missing > 0 then
-          install_missing_parsers(missing)
-        end
-      end)
     end
   },
 
@@ -250,16 +113,17 @@ return {
     end
   },
 
-  -- Mason: portable LSP installer. On NixOS this requires nix-ld for
-  -- downloaded Linux binaries to run.
+  -- Mason: portable LSP installer (disabled on NixOS where it doesn't work)
   {
     "williamboman/mason.nvim",
+    enabled = not is_nixos,
     config = function()
       require("mason").setup()
     end
   },
   {
     "williamboman/mason-lspconfig.nvim",
+    enabled = not is_nixos,
     dependencies = { "williamboman/mason.nvim" },
     config = function()
       require("mason-lspconfig").setup({
@@ -438,7 +302,7 @@ return {
 
   {
     "taproot-wizards/bitcoin-script-hints.nvim",
-    dependencies = { "nvim-treesitter" },
+    dependencies = { "nvim-treesitter/nvim-treesitter" },
     config = function()
       require("bitcoin-script-hints").setup()
     end