diff --git a/.github/dependabot.yml b/.github/dependabot.yml
new file mode 100644
index 0000000000..ba29cb1dad
--- /dev/null
+++ b/.github/dependabot.yml
@@ -0,0 +1,10 @@
+version: 2
+updates:
+- package-ecosystem: github-actions
+  directory: "/"
+  schedule:
+    interval: daily
+  open-pull-requests-limit: 10
+  commit-message:
+    prefix: "chore"
+    include: "scope"
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 6d51a7b20f..cfdb564301 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -8,29 +8,27 @@ on:
 
 jobs:
   build:
-    runs-on: ${{ matrix.os }}
+    runs-on: ubuntu-latest
+    continue-on-error: ${{ matrix.experimental }}
     strategy:
-      fail-fast: false
       matrix:
-        os: [ubuntu-latest]
         emacs_version:
-          - 25.1
-          - 25.2
-          - 25.3
           - 26.1
           - 26.2
           - 26.3
           - 27.1
           - 27.2
-          - snapshot
+          - 28.1
+          - 29.1
+        experimental: [false]
         include:
-          - os: macos-latest
-            emacs_version: 27.2
+          - emacs_version: snapshot
+            experimental: true
     steps:
     - uses: purcell/setup-emacs@master
       with:
         version: ${{ matrix.emacs_version }}
 
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
     - name: Check startup
       run: ./test-startup.sh
diff --git a/.gitignore b/.gitignore
index d03d13d586..2905347d18 100644
--- a/.gitignore
+++ b/.gitignore
@@ -17,6 +17,7 @@ CVS
 cookies
 /newsticker
 \#*
+/tree-sitter
 /elpa
 /elpa-*
 site-lisp/package/
diff --git a/README.md b/README.md
index a47ed06a7d..e0b7479802 100644
--- a/README.md
+++ b/README.md
@@ -27,7 +27,7 @@ in the approximate order of how much I use them, from most to least:
 * Erlang
 
 In particular, there's a nice config for *autocompletion* with
-[company](https://company-mode.github.io/), and
+[corfu](https://github.com/minad/corfu), and
 `flymake` (re-using backends from [flycheck](http://www.flycheck.org))
 is used to immediately highlight syntax errors in Ruby, Python,
 Javascript, Haskell and a number of other languages.
@@ -36,11 +36,12 @@ LSP support is provided using `eglot`.
 
 ## Supported Emacs versions
 
-The config should run on Emacs 25.1 or greater and is designed to
-degrade smoothly - see the CI build - but note that much newer
-versions are required for an increasing number of key packages, so to
-get full functionality you should use the latest Emacs version
-available to you.
+Use the latest released Emacs version available to you. The author
+typically uses the latest stable version.
+
+The config should run on Emacs 26.1 or greater and is designed to
+degrade smoothly - see the CI build - but even basic enhancements
+like completion may be unavailable if your Emacs is too old.
 
 Some Windows users might need to follow
 [these instructions](http://xn--9dbdkw.se/diary/how_to_enable_GnuTLS_for_Emacs_24_on_Windows/index.en.html)
diff --git a/init.el b/init.el
index 003e1a1e11..e188779ebc 100644
--- a/init.el
+++ b/init.el
@@ -9,10 +9,10 @@
 ;; Produce backtraces when errors occur: can be helpful to diagnose startup issues
 ;;(setq debug-on-error t)
 
-(let ((minver "25.1"))
+(let ((minver "26.1"))
   (when (version< emacs-version minver)
     (error "Your Emacs is too old -- this config requires v%s or higher" minver)))
-(when (version< emacs-version "26.1")
+(when (version< emacs-version "27.1")
   (message "Your Emacs is old, and some functionality in this config will be disabled. Please upgrade if possible."))
 
 (add-to-list 'load-path (expand-file-name "lisp" user-emacs-directory))
@@ -66,7 +66,7 @@
 (require 'init-recentf)
 (require 'init-minibuffer)
 (require 'init-hippie-expand)
-(require 'init-company)
+(require 'init-corfu)
 (require 'init-windows)
 (require 'init-sessions)
 (require 'init-mmm)
@@ -128,14 +128,13 @@
 (require 'init-folding)
 (require 'init-dash)
 
-;;(require 'init-twitter)
-;; (require 'init-mu)
 (require 'init-ledger)
+(require 'init-lua)
+
 ;; Extra packages which don't require any configuration
 
 (require-package 'sudo-edit)
 (require-package 'gnuplot)
-(require-package 'lua-mode)
 (require-package 'htmlize)
 (when *is-a-mac*
   (require-package 'osx-location))
@@ -151,6 +150,11 @@
 
 (require 'init-direnv)
 
+(when (and (require 'treesit nil t)
+           (fboundp 'treesit-available-p)
+           (treesit-available-p))
+  (require 'init-treesitter))
+
 
 
 ;; Allow access from emacsclient
diff --git a/lisp/init-clojure.el b/lisp/init-clojure.el
index 0961d9979e..8c5e6329c1 100644
--- a/lisp/init-clojure.el
+++ b/lisp/init-clojure.el
@@ -4,13 +4,14 @@
 
 ;; See also init-clojure-cider.el
 
-(when (maybe-require-package 'clojure-mode)
+(when (or (maybe-require-package 'clojure-ts-mode)
+          (maybe-require-package 'clojure-mode))
   (require-package 'cljsbuild-mode)
   (require-package 'elein)
 
   (with-eval-after-load 'clojure-mode
-    (add-hook 'clojure-mode-hook 'sanityinc/lisp-setup)
-    (add-hook 'clojure-mode-hook 'subword-mode)))
+    (dolist (m '(clojure-mode-hook clojure-ts-mode-hook))
+      (add-hook m 'sanityinc/lisp-setup))))
 
 
 (provide 'init-clojure)
diff --git a/lisp/init-corfu.el b/lisp/init-corfu.el
new file mode 100644
index 0000000000..3119df3469
--- /dev/null
+++ b/lisp/init-corfu.el
@@ -0,0 +1,39 @@
+;;; init-corfu.el --- Interactive completion in buffers -*- lexical-binding: t -*-
+;;; Commentary:
+;;; Code:
+
+;; WAITING: haskell-mode sets tags-table-list globally, breaks tags-completion-at-point-function
+;; TODO Default sort order should place [a-z] before punctuation
+
+(setq tab-always-indent 'complete)
+(when (maybe-require-package 'orderless)
+  (with-eval-after-load 'vertico
+    (require 'orderless)
+    (setq completion-styles '(orderless basic))))
+(setq completion-category-defaults nil
+      completion-category-overrides nil)
+(setq completion-cycle-threshold 4)
+
+(when (maybe-require-package 'corfu)
+  (setq-default corfu-auto t)
+  (with-eval-after-load 'eshell
+    (add-hook 'eshell-mode-hook (lambda () (setq-local corfu-auto nil))))
+  (setq-default corfu-quit-no-match 'separator)
+  (add-hook 'after-init-hook 'global-corfu-mode)
+
+
+
+  (with-eval-after-load 'corfu
+    (corfu-popupinfo-mode))
+
+  ;; Make Corfu also work in terminals, without disturbing usual behaviour in GUI
+  (when (maybe-require-package 'corfu-terminal)
+    (with-eval-after-load 'corfu
+      (corfu-terminal-mode)))
+
+  ;; TODO: https://github.com/jdtsmith/kind-icon
+  )
+
+
+(provide 'init-corfu)
+;;; init-corfu.el ends here
diff --git a/lisp/init-csv.el b/lisp/init-csv.el
index 3dfd8e02b8..77af1359c4 100644
--- a/lisp/init-csv.el
+++ b/lisp/init-csv.el
@@ -2,11 +2,10 @@
 ;;; Commentary:
 ;;; Code:
 
-(require-package 'csv-mode)
+(when (maybe-require-package 'csv-mode)
+  (add-auto-mode 'csv-mode "\\.[Cc][Ss][Vv]\\'")
 
-(add-auto-mode 'csv-mode "\\.[Cc][Ss][Vv]\\'")
-
-(setq csv-separators '("," ";" "|" " "))
+  (setq csv-separators '("," ";" "|" " ")))
 
 (provide 'init-csv)
 ;;; init-csv.el ends here
diff --git a/lisp/init-editing-utils.el b/lisp/init-editing-utils.el
index 55f13c45e7..bf4b51a974 100644
--- a/lisp/init-editing-utils.el
+++ b/lisp/init-editing-utils.el
@@ -64,18 +64,10 @@
 (require-package 'mode-line-bell)
 (add-hook 'after-init-hook 'mode-line-bell-mode)
 
-
-
-(when (maybe-require-package 'beacon)
-  (setq-default beacon-lighter "")
-  (setq-default beacon-size 20)
-  (add-hook 'after-init-hook 'beacon-mode))
-
 
 
-;;; Newline behaviour
+;;; Newline behaviour (see also electric-indent-mode, enabled above)
 
-(global-set-key (kbd "RET") 'newline-and-indent)
 (defun sanityinc/newline-at-end-of-line ()
   "Move to end of line, enter a newline, and reindent."
   (interactive)
@@ -153,6 +145,9 @@
 
 ;;; Handy key bindings
 
+(with-eval-after-load 'help
+  (define-key help-map "A" 'describe-face))
+
 (global-set-key (kbd "C-.") 'set-mark-command)
 (global-set-key (kbd "C-x C-.") 'pop-global-mark)
 
diff --git a/lisp/init-flymake.el b/lisp/init-flymake.el
index 22078f2ef6..1b964947a8 100644
--- a/lisp/init-flymake.el
+++ b/lisp/init-flymake.el
@@ -8,14 +8,15 @@
 (when (maybe-require-package 'flymake-flycheck)
   ;; Disable flycheck checkers for which we have flymake equivalents
   (with-eval-after-load 'flycheck
-    (setq-default flycheck-disabled-checkers
-                  (append (default-value 'flycheck-disabled-checkers)
-                          '(emacs-lisp emacs-lisp-checkdoc emacs-lisp-package))))
+    (setq-default
+     flycheck-disabled-checkers
+     (append (default-value 'flycheck-disabled-checkers)
+             '(emacs-lisp emacs-lisp-checkdoc emacs-lisp-package sh-shellcheck))))
 
   (defun sanityinc/enable-flymake-flycheck ()
     (setq-local flymake-diagnostic-functions
-                (append flymake-diagnostic-functions
-                        (flymake-flycheck-all-chained-diagnostic-functions))))
+                (seq-uniq (append flymake-diagnostic-functions
+                                  (flymake-flycheck-all-chained-diagnostic-functions)))))
 
   (add-hook 'flymake-mode-hook 'sanityinc/enable-flymake-flycheck)
   (add-hook 'prog-mode-hook 'flymake-mode)
@@ -23,12 +24,17 @@
 
 (with-eval-after-load 'flymake
   ;; Provide some flycheck-like bindings in flymake mode to ease transition
+  (define-key flymake-mode-map (kbd "C-c ! l") 'flymake-show-buffer-diagnostics)
   (define-key flymake-mode-map (kbd "C-c ! n") 'flymake-goto-next-error)
   (define-key flymake-mode-map (kbd "C-c ! p") 'flymake-goto-prev-error)
   (define-key flymake-mode-map (kbd "C-c ! c") 'flymake-start))
 
 (unless (version< emacs-version "28.1")
-  (setq eldoc-documentation-function 'eldoc-documentation-compose))
+  (setq eldoc-documentation-function 'eldoc-documentation-compose)
+
+  (add-hook 'flymake-mode-hook
+            (lambda ()
+              (add-hook 'eldoc-documentation-functions 'flymake-eldoc-function nil t))))
 
 (provide 'init-flymake)
 ;;; init-flymake.el ends here
diff --git a/lisp/init-git.el b/lisp/init-git.el
index d3d57dec1e..fac54186e9 100644
--- a/lisp/init-git.el
+++ b/lisp/init-git.el
@@ -15,7 +15,7 @@
 (require-package 'git-link)
 
 (when (maybe-require-package 'magit)
-  (setq-default magit-diff-refine-hunk t)
+  (setq-default magit-diff-refine-hunk 'all)
 
   ;; Hint: customize `magit-repository-directories' so that you can use C-u M-F12 to
   ;; quickly open magit on any one of your projects.
diff --git a/lisp/init-github.el b/lisp/init-github.el
index f5b8b4707f..e82e2b5c1d 100644
--- a/lisp/init-github.el
+++ b/lisp/init-github.el
@@ -12,5 +12,8 @@
 (maybe-require-package 'forge)
 (maybe-require-package 'github-review)
 
+(when (maybe-require-package 'flymake-actionlint)
+  (add-hook 'yaml-mode-hook 'flymake-actionlint-action-load-when-actions-file))
+
 (provide 'init-github)
 ;;; init-github.el ends here
diff --git a/lisp/init-gui-frames.el b/lisp/init-gui-frames.el
index 2e49da8a4d..5fb5f937ea 100644
--- a/lisp/init-gui-frames.el
+++ b/lisp/init-gui-frames.el
@@ -88,6 +88,10 @@
 
 (require-package 'disable-mouse)
 
+
+(when (fboundp 'pixel-scroll-precision-mode)
+  (pixel-scroll-precision-mode))
+
 
 (provide 'init-gui-frames)
 ;;; init-gui-frames.el ends here
diff --git a/lisp/init-javascript.el b/lisp/init-javascript.el
index 3ab2fbf260..952dc5b207 100644
--- a/lisp/init-javascript.el
+++ b/lisp/init-javascript.el
@@ -48,19 +48,21 @@
   (sanityinc/major-mode-lighter 'js2-jsx-mode "JSX2"))
 
 
-
+(require 'derived)
 (when (and (or (executable-find "rg") (executable-find "ag"))
            (maybe-require-package 'xref-js2))
   (when (executable-find "rg")
     (setq-default xref-js2-search-program 'rg))
+
   (defun sanityinc/enable-xref-js2 ()
     (add-hook 'xref-backend-functions #'xref-js2-xref-backend nil t))
-  (with-eval-after-load 'js
-    (define-key js-mode-map (kbd "M-.") nil)
-    (add-hook 'js-mode-hook 'sanityinc/enable-xref-js2))
+
+  (let ((base-mode (if (fboundp 'js-base-mode) 'js-base-mode 'js-mode)))
+    (with-eval-after-load 'js
+      (add-hook (derived-mode-hook-name base-mode) 'sanityinc/enable-xref-js2)
+      (define-key js-mode-map (kbd "M-.") nil)))
   (with-eval-after-load 'js2-mode
-    (define-key js2-mode-map (kbd "M-.") nil)
-    (add-hook 'js2-mode-hook 'sanityinc/enable-xref-js2)))
+    (define-key js2-mode-map (kbd "M-.") nil)))
 
 
 
diff --git a/lisp/init-ledger.el b/lisp/init-ledger.el
index 44727531d7..80a0163ab6 100644
--- a/lisp/init-ledger.el
+++ b/lisp/init-ledger.el
@@ -13,7 +13,8 @@
     (define-key ledger-mode-map (kbd "C-o") 'open-line))
 
   (setq ledger-highlight-xact-under-point nil
-        ledger-use-iso-dates nil)
+        ledger-use-iso-dates nil
+        ledger-mode-should-check-version nil)
 
   (with-eval-after-load 'ledger-mode
     (when (memq window-system '(mac ns))
diff --git a/lisp/init-lisp.el b/lisp/init-lisp.el
index b974f206f5..73b8f57593 100644
--- a/lisp/init-lisp.el
+++ b/lisp/init-lisp.el
@@ -47,7 +47,7 @@
   (add-hook 'after-init-hook 'ipretty-mode))
 
 
-(defun sanityinc/make-read-only (expression out-buffer-name)
+(defun sanityinc/make-read-only (_expression out-buffer-name &rest _)
   "Enable `view-mode' in the output buffer - if any - so it can be closed with `\"q\"."
   (when (get-buffer out-buffer-name)
     (with-current-buffer out-buffer-name
@@ -178,26 +178,10 @@ there is no current file, eval the current buffer."
   "Enable features useful in any Lisp mode."
   (run-hooks 'sanityinc/lispy-modes-hook))
 
-(defun sanityinc/emacs-lisp-setup ()
-  "Enable features useful when working with elisp."
-  (set-up-hippie-expand-for-elisp))
-
-(defconst sanityinc/elispy-modes
-  '(emacs-lisp-mode ielm-mode)
-  "Major modes relating to elisp.")
-
-(defconst sanityinc/lispy-modes
-  (append sanityinc/elispy-modes
-          '(lisp-mode inferior-lisp-mode lisp-interaction-mode))
-  "All lispy major modes.")
-
 (require 'derived)
 
-(dolist (hook (mapcar #'derived-mode-hook-name sanityinc/lispy-modes))
-  (add-hook hook 'sanityinc/lisp-setup))
-
-(dolist (hook (mapcar #'derived-mode-hook-name sanityinc/elispy-modes))
-  (add-hook hook 'sanityinc/emacs-lisp-setup))
+(dolist (mode '(emacs-lisp-mode ielm-mode lisp-mode inferior-lisp-mode lisp-interaction-mode))
+  (add-hook (derived-mode-hook-name mode) 'sanityinc/lisp-setup))
 
 (when (boundp 'eval-expression-minibuffer-setup-hook)
   (add-hook 'eval-expression-minibuffer-setup-hook #'eldoc-mode))
diff --git a/lisp/init-lua.el b/lisp/init-lua.el
new file mode 100644
index 0000000000..60b7f7492d
--- /dev/null
+++ b/lisp/init-lua.el
@@ -0,0 +1,16 @@
+;;; init-lua.el --- Support for Lua programming -*- lexical-binding: t -*-
+;;; Commentary:
+;;; Code:
+
+(require-package 'lua-mode)
+
+(setq-default lua-indent-level 2)
+
+(reformatter-define lua-format
+  :program "lua-format"
+  :args '("--indent-width=2" "--no-use-tab")
+  :lighter "LuaFmt ")
+
+
+(provide 'init-lua)
+;;; init-lua.el ends here
diff --git a/lisp/init-minibuffer.el b/lisp/init-minibuffer.el
index a6f0cf3201..34039b9b27 100644
--- a/lisp/init-minibuffer.el
+++ b/lisp/init-minibuffer.el
@@ -6,14 +6,6 @@
 (when (maybe-require-package 'vertico)
   (add-hook 'after-init-hook 'vertico-mode)
 
-  (require-package 'orderless)
-  (with-eval-after-load 'vertico
-    (require 'orderless))
-
-  (defun sanityinc/use-orderless-in-minibuffer ()
-    (setq-local completion-styles '(substring orderless)))
-  (add-hook 'minibuffer-setup-hook 'sanityinc/use-orderless-in-minibuffer)
-
   (when (maybe-require-package 'embark)
     (with-eval-after-load 'vertico
       (define-key vertico-map (kbd "C-c C-o") 'embark-export)
@@ -22,7 +14,7 @@
   (when (maybe-require-package 'consult)
     (defmacro sanityinc/no-consult-preview (&rest cmds)
       `(with-eval-after-load 'consult
-         (consult-customize ,@cmds :preview-key (kbd "M-P"))))
+         (consult-customize ,@cmds :preview-key "M-P")))
 
     (sanityinc/no-consult-preview
      consult-ripgrep
@@ -30,17 +22,13 @@
      consult-bookmark consult-recent-file consult-xref
      consult--source-recent-file consult--source-project-recent-file consult--source-bookmark)
 
-    (when (maybe-require-package 'projectile)
-      (setq-default consult-project-root-function 'projectile-project-root))
-
-    (when (and (executable-find "rg") (maybe-require-package 'affe))
-      (defun sanityinc/affe-grep-at-point (&optional dir initial)
+    (when (and (executable-find "rg"))
+      (defun sanityinc/consult-ripgrep-at-point (&optional dir initial)
         (interactive (list prefix-arg (when-let ((s (symbol-at-point)))
                                         (symbol-name s))))
-        (affe-grep dir initial))
-      (global-set-key (kbd "M-?") 'sanityinc/affe-grep-at-point)
-      (sanityinc/no-consult-preview sanityinc/affe-grep-at-point)
-      (with-eval-after-load 'affe (sanityinc/no-consult-preview affe-grep)))
+        (consult-ripgrep dir initial))
+      (sanityinc/no-consult-preview sanityinc/consult-ripgrep-at-point)
+      (global-set-key (kbd "M-?") 'sanityinc/consult-ripgrep-at-point))
 
     (global-set-key [remap switch-to-buffer] 'consult-buffer)
     (global-set-key [remap switch-to-buffer-other-window] 'consult-buffer-other-window)
diff --git a/lisp/init-nix.el b/lisp/init-nix.el
index 47d886b9ee..6f8d235def 100644
--- a/lisp/init-nix.el
+++ b/lisp/init-nix.el
@@ -2,25 +2,12 @@
 ;;; Commentary:
 ;;; Code:
 
-(when (maybe-require-package 'nix-mode)
+(when (or (maybe-require-package 'nix-ts-mode)
+          (maybe-require-package 'nix-mode))
   (maybe-require-package 'nixpkgs-fmt)
-  (maybe-require-package 'nix-sandbox)
-  (maybe-require-package 'nix-buffer)
-
-  (when (maybe-require-package 'nixos-options)
-    (when (maybe-require-package 'company-nixos-options)
-      (with-eval-after-load 'company
-        (with-eval-after-load 'nix-mode
-          ;; Patch pending https://github.com/travisbhartwell/nix-emacs/pull/46
-          (with-eval-after-load 'company-nixos-options
-            (defun company-nixos--in-nix-context-p ()
-              (unless (executable-find "nix-build")
-                (or (derived-mode-p 'nix-mode 'nix-repl-mode)
-                    (let ((file-name (buffer-file-name (current-buffer))))
-                      (and file-name (equal "nix" (file-name-extension file-name))))))))
-
-          (add-to-list 'company-backends 'company-nixos-options))))))
 
+  (with-eval-after-load 'eglot
+    (add-to-list 'eglot-server-programs '((nix-mode nix-ts-mode) . ("nil")))))
 
 (provide 'init-nix)
 ;;; init-nix.el ends here
diff --git a/lisp/init-ocaml.el b/lisp/init-ocaml.el
index 209b180075..c3bf20b999 100644
--- a/lisp/init-ocaml.el
+++ b/lisp/init-ocaml.el
@@ -2,10 +2,6 @@
 ;;; Commentary:
 ;;; Code:
 
-(with-eval-after-load 'eglot
-  (put 'tuareg-mode 'eglot-language-id "ocaml")
-  (add-to-list 'eglot-server-programs '((tuareg-mode) . ("ocamllsp")) t))
-
 (when (maybe-require-package 'tuareg)
   (with-eval-after-load 'tuareg
     (defvar-local tuareg-previous-tuareg-buffer nil
diff --git a/lisp/init-org.el b/lisp/init-org.el
index ef409d3a2d..b651b7cb2e 100644
--- a/lisp/init-org.el
+++ b/lisp/init-org.el
@@ -363,7 +363,7 @@ typical word processor."
    'org-babel-load-languages
    (seq-filter
     (lambda (pair)
-      (featurep (intern (concat "ob-" (symbol-name (car pair))))))
+      (locate-library (concat "ob-" (symbol-name (car pair)))))
     '((R . t)
       (ditaa . t)
       (dot . t)
diff --git a/lisp/init-paredit.el b/lisp/init-paredit.el
index bd976e2c8e..60572be2d1 100644
--- a/lisp/init-paredit.el
+++ b/lisp/init-paredit.el
@@ -4,8 +4,9 @@
 
 (require-package 'paredit)
 
+
 (defun sanityinc/maybe-map-paredit-newline ()
-  (unless (or (memq major-mode '(inferior-emacs-lisp-mode cider-repl-mode))
+  (unless (or (derived-mode-p 'inferior-emacs-lisp-mode 'cider-repl-mode)
               (minibufferp))
     (local-set-key (kbd "RET") 'paredit-newline)))
 
@@ -15,8 +16,9 @@
   (diminish 'paredit-mode " Par")
   ;; Suppress certain paredit keybindings to avoid clashes, including
   ;; my global binding of M-?
-  (dolist (binding '("C-<left>" "C-<right>" "C-M-<left>" "C-M-<right>" "M-s" "M-?"))
-    (define-key paredit-mode-map (read-kbd-macro binding) nil)))
+  (dolist (binding '("RET" "C-<left>" "C-<right>" "C-M-<left>" "C-M-<right>" "M-s" "M-?"))
+    (define-key paredit-mode-map (read-kbd-macro binding) nil))
+  (define-key paredit-mode-map (kbd "M-<up>") 'paredit-splice-sexp-killing-backward))
 
 
 
@@ -34,9 +36,10 @@
 
 (defun sanityinc/conditionally-enable-paredit-mode ()
   "Enable paredit during lisp-related minibuffer commands."
-  (if (memq this-command paredit-minibuffer-commands)
-      (enable-paredit-mode)))
+  (when (memq this-command paredit-minibuffer-commands)
+    (enable-paredit-mode)))
 
+(add-hook 'sanityinc/lispy-modes-hook 'enable-paredit-mode)
 
 (provide 'init-paredit)
 ;;; init-paredit.el ends here
diff --git a/lisp/init-php.el b/lisp/init-php.el
index e45dfd62a8..e0aceef697 100644
--- a/lisp/init-php.el
+++ b/lisp/init-php.el
@@ -3,11 +3,7 @@
 ;;; Code:
 
 (when (maybe-require-package 'php-mode)
-  (maybe-require-package 'smarty-mode)
-
-  (when (maybe-require-package 'company-php)
-    (with-eval-after-load 'company
-      (add-to-list 'company-backends 'company-ac-php-backend))))
+  (maybe-require-package 'smarty-mode))
 
 (provide 'init-php)
 ;;; init-php.el ends here
diff --git a/lisp/init-projectile.el b/lisp/init-projectile.el
index df6928f1b0..61c8a9d6fe 100644
--- a/lisp/init-projectile.el
+++ b/lisp/init-projectile.el
@@ -9,7 +9,7 @@
   (setq-default projectile-mode-line-prefix " Proj")
 
   (when (executable-find "rg")
-    (setq-default projectile-generic-command "rg --files --hidden"))
+    (setq-default projectile-generic-command "rg --files --hidden -0"))
 
   (with-eval-after-load 'projectile
     (define-key projectile-mode-map (kbd "C-c p") 'projectile-command-map))
diff --git a/lisp/init-ruby.el b/lisp/init-ruby.el
index d6dd10095b..0c2e80ea8a 100644
--- a/lisp/init-ruby.el
+++ b/lisp/init-ruby.el
@@ -57,10 +57,7 @@
 ;;; Robe
 (when (maybe-require-package 'robe)
   (with-eval-after-load 'ruby-mode
-    (add-hook 'ruby-mode-hook 'robe-mode))
-  (with-eval-after-load 'robe
-    (with-eval-after-load 'company
-      (add-to-list 'company-backends 'company-robe))))
+    (add-hook 'ruby-mode-hook 'robe-mode)))
 
 
 
diff --git a/lisp/init-slime.el b/lisp/init-slime.el
index 6e0e3d46cf..e7183c3a20 100644
--- a/lisp/init-slime.el
+++ b/lisp/init-slime.el
@@ -2,14 +2,6 @@
 ;;; Commentary:
 ;;; Code:
 
-(require-package 'slime)
-(push (expand-file-name "contrib" (file-name-directory (locate-library "slime"))) load-path)
-
-(when (maybe-require-package 'slime-company)
-  (setq slime-company-completion 'fuzzy
-        slime-company-after-completion 'slime-company-just-one-space)
-  (with-eval-after-load 'slime-company
-    (add-to-list 'company-backends 'company-slime)))
 
 
 ;;; Lisp buffers
@@ -17,10 +9,8 @@
 (with-eval-after-load 'slime
   (setq slime-protocol-version 'ignore)
   (setq slime-net-coding-system 'utf-8-unix)
-  (let ((features '(slime-fancy slime-repl slime-fuzzy)))
-    (when (require 'slime-company nil t)
-      (push 'slime-company features))
-    (slime-setup features)) )
+  (let ((features '(slime-fancy slime-repl slime-fuzzy slime-autodoc)))
+    (slime-setup features)))
 
 
 ;;; REPL
diff --git a/lisp/init-sql.el b/lisp/init-sql.el
index 891ee4534d..ada34f5c99 100644
--- a/lisp/init-sql.el
+++ b/lisp/init-sql.el
@@ -110,13 +110,6 @@ This command currently blocks the UI, sorry."
                 (display-buffer (current-buffer))
                 (user-error "EXPLAIN failed")))))))))
 
-
-;; Submitted upstream as https://github.com/stanaka/dash-at-point/pull/28
-(with-eval-after-load 'sql
-  (with-eval-after-load 'dash-at-point
-    (add-to-list 'dash-at-point-mode-alist '(sql-mode . "psql,mysql,sqlite,postgis"))))
-
-
 (with-eval-after-load 'page-break-lines
   (add-to-list 'page-break-lines-modes 'sql-mode))
 
diff --git a/lisp/init-terraform.el b/lisp/init-terraform.el
index f24782ce59..edd2efb021 100644
--- a/lisp/init-terraform.el
+++ b/lisp/init-terraform.el
@@ -5,15 +5,13 @@
 ;;; Terraform
 
 (when (maybe-require-package 'terraform-mode)
-  (when (maybe-require-package 'company-terraform)
-    (with-eval-after-load 'terraform-mode
-      (company-terraform-init)
-
-      ;; I find formatters based on "reformatter" to be more reliable
-      ;; so I redefine `terraform-format-on-save-mode' here.
-      (when (maybe-require-package 'reformatter)
-        (reformatter-define terraform-format
-          :program "terraform" :args '("fmt" "-"))))))
+  ;; TODO: find/write a replacement for company-terraform
+  (with-eval-after-load 'terraform-mode
+    ;; I find formatters based on "reformatter" to be more reliable
+    ;; so I redefine `terraform-format-on-save-mode' here.
+    (when (maybe-require-package 'reformatter)
+      (reformatter-define terraform-format
+        :program "terraform" :args '("fmt" "-")))))
 
 (provide 'init-terraform)
 ;;; init-terraform.el ends here
diff --git a/lisp/init-treesitter.el b/lisp/init-treesitter.el
new file mode 100644
index 0000000000..7e168fbc8d
--- /dev/null
+++ b/lisp/init-treesitter.el
@@ -0,0 +1,69 @@
+;;; init-treesitter.el --- Enable Treesitter-based major modes -*- lexical-binding: t -*-
+;;; Commentary:
+;;; Code:
+
+;; You can download per-architecture pre-compiled release from
+;; https://github.com/emacs-tree-sitter/tree-sitter-langs Rename
+;; contained grammars to add prefix "libtree-sitter-", place in
+;; ~/.emacs.d/tree-sitter.
+;;
+;; Nix users can pre-install all grammars alongside their Emacs, see
+;; https://github.com/nix-community/emacs-overlay/issues/341
+;;
+;; Note that grammar files from different sources can be differently
+;; named and configured, so there could be different results. Some
+;; common remappings are included below.
+(setq treesit-load-name-override-list nil
+      major-mode-remap-alist nil)
+
+(defun sanityinc/auto-configure-treesitter ()
+  "Find and configure installed grammars, remap to matching -ts-modes if present.
+Return a list of languages seen along the way."
+  (let ((grammar-name-to-emacs-lang '(("c-sharp" . "csharp")
+                                      ("cpp" . "c++")
+                                      ("gomod" . "go-mod")
+                                      ("javascript" . "js")))
+        seen-grammars)
+    (dolist (dir (cons (expand-file-name "tree-sitter" user-emacs-directory)
+                       treesit-extra-load-path))
+      (when (file-directory-p dir)
+        (dolist (file (directory-files dir))
+          (let ((fname (file-name-sans-extension (file-name-nondirectory file))))
+            (when (string-match "libtree-sitter-\\(.*\\)" fname)
+              (let* ((file-lang (match-string 1 fname))
+                     (emacs-lang (or (cdr (assoc-string file-lang grammar-name-to-emacs-lang)) file-lang)))
+                ;; Override library if its filename doesn't match the Emacs name
+                (unless (or (memq (intern emacs-lang) seen-grammars)
+                            (string-equal file-lang emacs-lang))
+                  (let ((libname (concat "tree_sitter_" (replace-regexp-in-string "-" "_" file-lang))))
+                    (add-to-list 'treesit-load-name-override-list
+                                 (list (intern emacs-lang) fname libname))))
+                ;; If there's a corresponding -ts mode, remap the standard mode to it
+                (let ((ts-mode-name (intern (concat emacs-lang "-ts-mode")))
+                      (regular-mode-name (intern (concat emacs-lang "-mode"))))
+                  (when (fboundp ts-mode-name)
+                    (add-to-list 'major-mode-remap-alist
+                                 (cons regular-mode-name ts-mode-name))))
+                ;; Remember we saw this language so we don't squash its config when we
+                ;; find another lib later in the treesit load path
+                (push (intern emacs-lang) seen-grammars)))))))
+    seen-grammars))
+
+(sanityinc/auto-configure-treesitter)
+
+;; When there's js-ts-mode, we prefer it to js2-mode
+(when-let ((jsmap (alist-get 'js-mode major-mode-remap-alist)))
+  (add-to-list 'major-mode-remap-alist (cons 'js2-mode jsmap)))
+
+(when-let ((jsmap (alist-get 'clojure-mode major-mode-remap-alist)))
+  (add-to-list 'major-mode-remap-alist (cons 'clojurescript-mode 'clojurescript-ts-mode)))
+
+
+
+;; Default
+(setq treesit-font-lock-level 4)
+
+
+
+(provide 'init-treesitter)
+;;; init-treesitter.el ends here
diff --git a/lisp/init-utils.el b/lisp/init-utils.el
index cff9fab9c1..6b3f2f4307 100644
--- a/lisp/init-utils.el
+++ b/lisp/init-utils.el
@@ -51,18 +51,20 @@
 
 ;; Rename the current file
 
-(defun rename-this-file-and-buffer (new-name)
-  "Renames both current buffer and file it's visiting to NEW-NAME."
-  (interactive "sNew name: ")
-  (let ((name (buffer-name))
-        (filename (buffer-file-name)))
-    (unless filename
-      (error "Buffer '%s' is not visiting a file!" name))
-    (progn
-      (when (file-exists-p filename)
-        (rename-file filename new-name 1))
-      (set-visited-file-name new-name)
-      (rename-buffer new-name))))
+(if (fboundp 'rename-visited-file)
+    (defalias 'rename-this-file-and-buffer 'rename-visited-file)
+  (defun rename-this-file-and-buffer (new-name)
+    "Renames both current buffer and file it's visiting to NEW-NAME."
+    (interactive "sNew name: ")
+    (let ((name (buffer-name))
+          (filename (buffer-file-name)))
+      (unless filename
+        (error "Buffer '%s' is not visiting a file!" name))
+      (progn
+        (when (file-exists-p filename)
+          (rename-file filename new-name 1))
+        (set-visited-file-name new-name)
+        (rename-buffer new-name)))))
 
 
 ;; Browse current HTML file