이미 일상에서 쓰는 Emacs 31의 주요 변화들

Emacs 31 Is Around the Corner: The Changes I'm Already Daily Driving Rahul M. Juliato Rahul M. Juliato June 18, 2026 # emacs # emacs-31 # config Karthik Chikmagalur recently published another of his excellent "Even More Batteries Included with Emacs" posts, digging into lesser-known features that already ship with Emacs today. I wanted to write its mirror image. His post covers the batteries already in the box. Mine covers the ones arriving in Emacs 31. Emacs 31 isn't out yet, but I've been building it from both emacs-31 branch and master and daily driving it for months. Every time something new and useful lands, I fold it into Emacs Solo , my no-external-packages config, and mark it with a small ; EMACS-31 comment so I remember to revisit it once the release is official. This post walks those breadcrumbs. Every change below is one I'm touching in my config right now, with a note on what it does and why I keep it. None of it requires a package. It's all either on master already or close behind. One disclaimer: Emacs 31 is still in development (actually in pre-release phase), so names and defaults can shift before final release. Everything below is what I'm running as of mid-2026. If you're not building from emacs-31 branch or master , treat this as a preview of what's coming. Tree-sitter that just works If I had to pick the single change I'm happiest about, it's this one. For years, getting a *-ts-mode going meant manually populating treesit-language-source-alist , calling treesit-install-language-grammar , and praying your toolchain was set up to compile the grammar. In Emacs 31 a lot of that ceremony goes away: ( treesit-auto-install-grammar t ) ; EMACS-31 ( treesit-enabled-modes t ) ; EMACS-31 treesit-enabled-modes set to t switches the major modes that have a tree-sitter variant over to it, and treesit-auto-install-grammar makes Emacs offer to fetch and build the grammar when it's missing instead of erroring out. This is the treesit-auto package experience, except now the core does the work. The knock-on effect shows up all over my config. I used to keep lines like these around to teach Emacs where each grammar lives: ( add-to-list 'treesit-language-source-alist '( typescript "https://github.com/tree-sitter/tree-sitter-typescript" "master" "typescript/src" ) ) In Emacs 31 the grammar sources for languages like TypeScript, TSX, Rust, TOML, YAML and Dockerfile live inside the modes themselves, so I've got a trail of ;; EMACS-31 this is now defined on mode code comments marking every block I get to delete once 31 ships. I'll take less config that does the same job any day. There are many more tree-sitter improvements coming to Emacs. The developers have been working tirelessly on it, Yuan Fu, along with many others, have been continuously improving the tree-sitter experience across multiple areas. From better language support to usability and performance enhancements, tree-sitter in Emacs continues to evolve at a remarkable pace. A built-in markdown-ts-mode (experimental) Emacs 31 ships a markdown-ts-mode in the box, and this one is close to my heart. I started it. It grew out of a proposal I sent to emacs-devel back in early 2025, where the idea and the first version of the code were mine. I'd be doing the mode a disservice if I let you think it's a solo effort. Stéphane Marks came along a bit later, rolled up his sleeves, and has since become a co-author of the mode. He's the energy behind much of what makes it nice to use today. He didn't send a patch or two and move on; he stayed, pushing the mode well past what I'd sketched out and sweating the details that turn "it works" into "it's a pleasure." Much of the polish I'm about to brag about is his. The mode is ours now, and it's better for it. Watching an idea make the round trip from a mailing-list message to core code, and picking up a great collaborator on the way, is one of the most rewarding things about hanging around the Emacs community. ( use-package markdown-ts-mode :ensure nil :defer t ) It gives you more than colors, and these are the parts I want to show off: ✔️ Org users will feel at home. The keybindings and editing feel stay close to Org: navigating headings, folding sections, moving between structural elements. If your fingers know Org, you won't have to relearn Markdown. ✔️ Live, colored code blocks, even for non-tree-sitter languages. This is my favorite trick. A fenced code block gets fontified using the real major mode for that language, not dumped as flat monospace. It reaches Emacs' own internal modes too, so an ```elisp block lights up with true Emacs Lisp font-locking, and the other built-in modes do the same. You get proper syntax highlighting inside your code samples with no extra setup. ✔️ Inline image viewing. Image links render in the buffer, so a Markdown doc with screenshots or diagrams reads like a document, not a wall of  noise. And many more features discoverable and being developed. Together these make it feel like a comfortable place to write and read Markdown inside Emacs, not a syntax highlighter bolted onto .md files. One caveat I want to be upfront about: markdown-ts-mode is still experimental , and you have to opt into it. As the header of markdown-ts-mode.el notes, it isn't wired up to auto-mode-alist yet, so it won't take over .md files on its own. For now you pull in the library with M-x load-library RET markdown-ts-mode , then turn it on in a bufferf, or add it to auto-mode-alist yourself if you're feeling brave. Stéphane and I are working to get it considered ready by the next Emacs release, and that's where you come in. If you try it and hit rough edges, or it works great, we want to hear about it. Send feedback to the bug list with M-x report-emacs-bug , or reach out to me and Stéphane directly. Real-world use is what moves a mode from "experimental" to "done", so don't be shy. Many more screenshots here . Eglot rendering docs with markdown-ts (also, still experimental) Speaking of Markdown, Eglot in Emacs 31 can render LSP documentation using that same internal mode instead of falling back to plain text: ( eglot-documentation-renderer 'markdown-ts-view-mode ) ;; EMACS-31 ( eglot-code-action-indications nil ) ;; EMACS-31 markdown-ts-view-mode gives you formatted hover docs without pulling in anything extra. The same experimental caveat applies here, since it leans on markdown-ts-mode , so treat it as something to opt into rather than a finished default. I also turn off eglot-code-action-indications . The new inline "you can do a code action here" hints are clever, but some language servers make them noisy, so I keep them off. There's also some churn here: eglot-events-buffer-size is on its way out in favor of eglot-events-buffer-config , so I've left a ;; EMACS-31 -- do we still need it? note on the old variable to clean up later. eldoc at point A small one I'm fond of: ( eldoc-help-at-pt t ) ;; EMACS-31 With this on, eldoc shows the help text for whatever sits under the cursor, without me invoking anything. Paired with eldoc-echo-area-prefer-doc-buffer , it makes wandering through unfamiliar code feel more guided. Smarter, eager completion The minibuffer and completion machinery picked up a few new toggles: ( completion-eager-update t ) ;; EMACS-31 ( completion-eager-display 'auto ) ;; EMACS-31 ( minibuffer-visible-completions 'up-down ) ;; EMACS-31 completion-eager-update and completion-eager-display refresh the completion UI as you type instead of waiting for you to ask. If you don't run something like icomplete, setting eager display to t gives you a sharp out-of-the-box experience on its own. And minibuffer-visible-completions set to 'up-down lets you move through the visible candidates with the arrow keys, which feels natural at last. icomplete got attention too, and this is another one I had a direct hand in. Emacs 31 includes the patch from bug#75784 , which I proposed and worked on. It brings vertical in-buffer behavior and