The goal of lsp-bridge is to implement the fastest LSP client in the Emacs ecosystem.

Using Python multithreading techniques, lsp-bridge builds a high-speed cache between Emacs and the LSP server, ensuring that Emacs never gets stuck while providing a smooth and seamless code completion experience.

EmacsConf 2022 talk page

1. Install Emacs 28 or higher version
2. Install Python dependencies: pip3 install epc orjson sexpdata six paramiko rapidfuzz (orjson is optional, orjson is based on Rust, providing faster JSON parsing performance)
3. Install Elisp dependencies:

• markdown-mode
• yasnippet

4. Download this repository using git clone, and replace the load-path path in the configuration below.
5. Add the following code to your configuration file ~/.emacs:

(add-to-list 'load-path "<path-to-lsp-bridge>")

(require 'yasnippet)
(yas-global-mode 1)

(require 'lsp-bridge)
(global-lsp-bridge-mode)

• If you are using straight to install, you should use the following configuration to install:

(use-package lsp-bridge
  :straight '(lsp-bridge :type git :host github :repo "manateelazycat/lsp-bridge"
            :files (:defaults "*.el" "*.py" "acm" "core" "langserver" "multiserver" "resources")
            :build (:not compile))
  :init
  (global-lsp-bridge-mode))

Please note that:

1. When using lsp-bridge, please first disable other completion plugins such as lsp-mode, eglot, company, corfu, etc. Lsp-bridge provides a complete solution from completion backend, frontend to multi-backend fusion.
2. When the completion menu pops up, acm-mode will be automatically enabled, and when the completion menu disappears, acm-mode will be automatically disabled. Please do not manually add acm-mode to any mode-hook or manually execute acm-mode.

Lsp-bridge works out of the box. After installing the corresponding LSP server and mode plugin for the language, you can start coding directly without any additional settings.

It should be noted that lsp-bridge has three scanning modes:

1. When the .git directory is detected (determined by the command git rev-parse --is-inside-work-tree), lsp-bridge will scan the entire directory to provide completion.
2. When the .git directory is not detected, lsp-bridge only provides single-file completion for the opened file.
3. Through the lsp-bridge-get-project-path-by-filepath function customized by setq, the input parameter is the path string of the opened file, the output parameter is the project directory path, lsp-bridge will provide completion based on the output directory path.

lsp-bridge can also provide code syntax completion for files on a remote server, similar to VSCode. Providing remote code completion is very useful when dealing with large and complex software that requires high resource demands or has complex environment configuration. The following are the steps to configure remote code completion:

1. Install lsp-bridge and the corresponding LSP server on the remote server.
2. Start the lsp-bridge service: python3 lsp-bridge/lsp_bridge.py
3. Use the command lsp-bridge-open-remote-file to open the remote file and enter the username, server IP, ssh port (default: 22), and file path, such as user@ip:[ssh_port]:/path/file.

Once the remote file is opened, lsp-bridge will automatically display the code completion menu. The remote completion principle of lsp-bridge is as follows:

1. Login to the remote server with SSH authentication and access and edit the remote file.
2. When editing the remote file locally, incremental diff sequences are sent to the lsp-bridge server in real-time. The server will rebuild the latest content of the file based on the incremental diff sequence and call the LSP server to complete the syntax calculation.
3. After calculating the LSP completion menu items, lsp-bridge will send the completion data to the local computer and render the completion menu.

If the completion menu does not appear, log in to the remote server and check the terminal output of lsp_bridge.py. Generally, incomplete installation of the service-side LSP server is the cause.

lsp-bridge first looks for the content of the first *.pub file in the ~/.ssh directory as the public key credential for logging into the remote server. If public key login fails, the user will be prompted to enter the login password. lsp-bridge does not store the server login password in a file. To avoid repeatedly entering the password, it is recommended that you use the public key method to log in to the remote server.

• lsp-bridge-find-def: jump to the definition
• lsp-bridge-find-def-other-window: jump to the definition in other-window
• lsp-bridge-find-def-return: return to the location before calling lsp-bridge-find-def
• lsp-bridge-find-type-def: Jump to the position of type definition.
• lsp-bridge-find-type-def-other-window: Jump to the position of type definition in another window.
• lsp-bridge-find-impl: jump to the implementation
• lsp-bridge-find-impl-other-window: jump to the implementation in other-window
• lsp-bridge-find-references: traverse across code references (forked from color-rg.el)
• lsp-bridge-popup-documentation: lookup documentation of symbol under the cursor
• lsp-bridge-popup-documentation-scroll-up: scroll up popup document.
• lsp-bridge-popup-documentation-scroll-down: scroll down popup document.
• lsp-bridge-rename: rename symbol under the cursor
• lsp-bridge-diagnostic-jump-next: Jump to the next diagnostic position
• lsp-bridge-diagnostic-jump-prev: Jump to the previous diagnostic position
• lsp-bridge-diagnostic-list: List all diagnostic information
• lsp-bridge-diagnostic-copy: Copy the current diagnostic information to the clipboard
• lsp-bridge-diagnostic-ignore: Insert comment to ignore the current diagnosis
• lsp-bridge-code-action: Popup code action menu, you can pass special actin-kind to fix, action-kind can use one of "quickfix", "refactor", "refactor.extract", "refactor.inline", "refactor.rewrite", "source", "source.organizeImports", "source.fixAll"
• lsp-bridge-workspace-list-symbols: List all symbols in workspace and jump to the symbol definition
• lsp-bridge-signature-help-fetch: show signature help in minibuffer manually (move cursor to parameters area will show signature help automatically)
• lsp-bridge-popup-complete-menu: Manually popup the completion menu, you only need this command when turn on option lsp-bridge-complete-manually
• lsp-bridge-restart-process: restart lsp-bridge process (only used for development)
• lsp-bridge-toggle-sdcv-helper: Switch dictionary completion assistant
• lsp-bridge-peek-abort: Close peek window (default binding to C-g)
• lsp-bridge-peek-list-next-line: Select the next definition or reference (default binding to M-S-n)
• lsp-bridge-peek-list-prev-line: Select the previous definition or reference (default binding to M-S-p)
• lsp-bridge-peek-file-content-next-line: Scroll down one line in the peek window file content (default binding to M-n)
• lsp-bridge-peek-file-content-prev-line: Scroll up one line in the peek window file content (default binding to M-p)
• lsp-bridge-peek-jump: Jump to the location of the definition or reference (default binding to M-l j)
• lsp-bridge-peek-jump-back: Jump back to the original position (default bound to M-l b)
• lsp-bridge-peek-through: View one symbol in the peek window
• lsp-bridge-peek-tree-previous-branch: Select the previous branch at the same level in the browsing history (default binding to <up>)
• lsp-bridge-peek-tree-next-branch: Select the next branch at the same level in the browsing history (default binding to <down>)
• lsp-bridge-peek-tree-previous-node: Select the previous higher-level node in the browsing history (default binding to <left>)
• lsp-bridge-peek-tree-next-node: Select the next lower-level node in the browsing history (default binding to <right>)

• lsp-bridge-c-lsp-server: C language server, you can choose clangd orccls
• lsp-bridge-elixir-lsp-server: Elixir language server, you can choose elixirLS(default) orlexical
• lsp-bridge-python-lsp-server: Python language server, you can choose pyright, jedi, python-ms, pylsp, ruff, it's important to note that lsp-bridge-multi-lang-server-mode-list has a higher priority than lsp-bridge-single-lang-server-mode-list. If you only want to use a single server, please first remove the python-mode setting from lsp-bridge-multi-lang-server-mode-list.
• lsp-bridge-php-lsp-server: PHP language server, you can choose intelephense or phpactor
• lsp-bridge-tex-lsp-server: LaTeX language server, you can choose texlab ordigestif
• lsp-bridge-csharp-lsp-server: C# language server, you can choose omnisharp-mono oromnisharp-dotnet, note that you need to give execute permissions to the OmniSharp file
• lsp-bridge-python-multi-lsp-server: Python multi-language servers, you can choose pyright_ruff, jedi_ruff, python-ms_ruff, pylsp_ruff
• lsp-bridge-nix-lsp-server: Nix language server, you can choose rnix-lsp or nil

• lsp-bridge-python-command: The path of the python command, if you use conda, you may customize this option. Windows platform using python.exe rather than python3, if lsp-bridge can’t work, try set to python3
• lsp-bridge-complete-manually: Only popup completion menu when user call lsp-bridge-popup-complete-menu command, default is nil
• lsp-bridge-get-workspace-folder: You need to put multiple project in a workspace directory in Java before you can jump function defintion normally. This function can be customized, the function input is the project path and returns the workspace directory corresponding
• lsp-bridge-default-mode-hooks: The list of modes that automatically start lsp-bridge, you can customize this option to control the scope of starting lsp-bridge
• lsp-bridge-org-babel-lang-list: list of language to support org-mode code block completion, nil enable all languages, default is nil
• lsp-bridge-find-def-fallback-function: When LSP cannot find a definition, you can customize this function for candidate jumping, such as binding the citre or dumb-jump definition jump function
• lsp-bridge-find-ref-fallback-function: When LSP cannot find a reference, you can customize this function for candidate jumping, such as binding the citre or dumb-jump definition jump function
• lsp-bridge-enable-completion-in-string: Enable completion pop-up within strings, default is off
• lsp-bridge-enable-completion-in-minibuffer: Enable pop-completion up in Minibuffer, disabled by default
• lsp-bridge-enable-diagnostics: code diagnostic, enable by default
• lsp-bridge-enable-hover-diagnostic: show diagnostic tooltip when cursor hover diagnostic place, disable by default
• lsp-bridge-enable-search-words: index the word of the file, enable by default
• lsp-bridge-enable-auto-format-code: automatic format code, disable by default
• lsp-bridge-enable-signature-help: show function parameter in minibufer, enable by default
• lsp-bridge-enable-log: enable LSP message log, disable by default, only enable this option for development purposes, usually do not turn on this option to avoid affecting performance
• lsp-bridge-enable-debug: enable program debugging, disable by default
• lsp-bridge-disable-backup: forbidden version manage of emacs, enable by default
• lsp-bridge-code-action-enable-popup-menu: enable code action popup menu, enable by default
• lsp-bridge-diagnostic-fetch-idle: diagnostic delay, start pulling diagnostic information 0.5 second after stopping typing
• lsp-bridge-signature-show-function: The function used for displaying signature info, default show message in minibuffer, set lsp-bridge-signature-show-with-frame to show signature info in frame
• lsp-bridge-signature-show-with-frame-position: When using lsp-bridge-signature-show-with-frame to display signature information, this option defines the position of the pop-up signature information, the default is "bottom-right", you can also choose "top-left", "top-right", "bottom-left", "point"
• lsp-bridge-completion-popup-predicates: the predicate function for completion menu, completion menu popup after all the functions pass
• lsp-bridge-completion-stop-commands: completion menu will not popup if these commands are executed
• lsp-bridge-completion-hide-characters: The default value is ‘(":" ";" "(" ")" "[" "]" "{" "}" ", " "\""), the completion menu does not pop up when the cursor is behind these characters. You can customize this option to remove this restriction, or call the lsp-bridge-popup-complete-menu command to force the menu to pop up
• lsp-bridge-user-langserver-dir: the dir where user place langserver configuration file, if the configuration file name in the dir is the same as that in lsp-bridge/langserver , lsp-bridge will use the configuration file in this dir
• lsp-bridge-user-multiserver-dir: the dir where user place multiserver configuration file, if the configuration file name in the dir is the same as that in lsp-bridge/multiserver , lsp-bridge will use the configuration file in this dir
• lsp-bridge-symbols-enable-which-func: Using lsp backend for which-func, disable by default
• lsp-bridge-enable-org-babel: Use lsp completion in org babel, disable by default, if unable to complete, please make sure the string after begin_src exists in the org-src-lang-modes variable
• lsp-bridge-peek-file-content-height: Display how many lines of file content in peek windows
• lsp-bridge-peek-list-height: Select the next option for definition and reference
• lsp-bridge-peek-ace-keys: Keys to press when performing lsp-bridge-peek-through
• lsp-bridge-peek-ace-cancel-keys: Keys to exit lsp-bridge-peek-through
• acm-frame-background-dark-color: Menu background color in dark theme
• acm-frame-background-light-color: Menu background color in light theme
• acm-enable-doc: Whether the complete menu display the help document
• acm-enable-doc-markdown-render: Richly render Markdown for completion popups, you can choose 'async, t or nil. When set to 'async, styles are applied asynchronously, choose t, styles are applied synchronously and will slow down the completion speed, default is 'async
• acm-enable-icon: Whether the completion menu displays icons (Many macOS users have reported that emacs-plus28 cannot display icons properly, showing colored squares instead. There are two ways to solve this: install Emacs Mac Port or add the --with-rsvg option to the brew command when compiling Emacs yourself)
• acm-enable-tabnine: Enable tabnine support， enable by default， when enable need execute lsp-bridge-install-tabnine command to install TabNine, and it can be used. TabNine will consume huge CPUs, causing your entire computer to be slow. If the computer performance is not good, it is not recommended to enable this option
• acm-enable-codeium: Enable Codeium support, when enable need execute lsp-bridge-install-update-codeium command to install Codeium, then execute lsp-bridge-codeium-auth command to get auth token and execute lsp-bridge-codeium-input-auth-token command to get API Key, and it can be used.
• acm-enable-copilot: Enable copilot support, firstly, purchase the Copilot service by https://github.com/features/copilot , when enable need install agent first npm install -g copilot-node-server, then execute lsp-bridge-copilot-login, lsp-bridge will display User Code in the Minibuffer, copy the User Code to the opened Copilot page to complete the login.
• acm-enable-search-file-words: Whether the complete menu display the word of the file, enable by default
• acm-enable-quick-access: Whether to display an index after the icon, quickly select candidate words using Alt Number, default is off
• acm-quick-access-use-number-select: Whether to use number keys for quick selection of candidate words, default is off, turning on this option may sometimes interfere with number input or accidentally select candidate words
• acm-enable-yas: yasnippet completion, enable by default
• acm-enable-citre: Integration with citre(ctags). Enable this to add citre (ctags) backend (disabled by default)
• acm-doc-frame-max-lines: Max line number of help documentation, default is 20
• acm-candidate-match-function: The complete menu matching algorithm, the algorithm prefix of orderless-* needs to be installed additional orderless
• acm-completion-backend-merge-order: Display order of completion backends. By default, multiple completion backends are merged in the order of LSP, Templates, and TabNine, and then the remaining templates and LSP completion options are displayed. You can adjust the order of completion back-end merging according to your needs
• acm-backend-lsp-candidate-min-length: The minimum characters to trigger lsp completion, default is 0
• acm-backend-elisp-candidate-min-length: The minimum characters to trigger elisp completion, default is 0
• acm-backend-yas-candidate-min-length: The minimum characters to trigger yasnippet completion, default is 0
• acm-backend-search-file-words-candidate-min-length: The minimum characters to trigger search file words completion, default is 0
• acm-backend-search-file-words-max-number: Search Words completion candidate limit, default is 10
• acm-backend-search-file-words-enable-fuzzy-match: Search Words completion candidate fuzzy match, disable by default
• acm-backend-search-file-words-enable-fuzzy-match-threshold: Search Words completion candidate fuzzy match threshold, Filter out words with a ratio lower than the threshold, default is 50
• acm-backend-codeium-candidate-min-length: The minimum characters to trigger codeium completion, default is 0
• acm-backend-lsp-enable-auto-import: automatic insert import code, enable by default
• acm-backend-lsp-candidate-max-length: Maximum length of LSP candidate, some language, such as Java, argument list is very long, you can increase the value of this option to see clear argument list
• acm-backend-yas-candidates-number: yasnippet display number， 2 by default
• acm-backend-citre-keyword-complete: Completion is performed according to the keywords of each mode defined by acm-backend-citre-keywords-alist, which takes effect only after citre is enabled.
• acm-backend-search-sdcv-words-dictionary: StarDict dictionary for word completion, default is kdic-ec-11w, you can replace it with StarDict dictionary path, example, if you have dictionary /usr/share/stardict/dic/stardict-oxford-gb-formated-2.4.2/oxford-gb-formated.ifo, you need set this value to /usr/share/stardict/dic/stardict-oxford-gb-formated-2.4.2/oxford-gb-formated, not include .ifo extension.
• acm-enable-preview: enable Tab-and-Go completion, commands like acm-select-* will select and preview other candidate and further input will then commit this candidate, disable by default

The configuration for the LSP server of each language in lsp-bridge is stored in lsp-bridge/langserver.

In most cases, you can customize the server configuration according to the following priority order:

1. lsp-bridge-get-single-lang-server-by-project: A user-defined function that takes project-path and file-path as input parameters and returns the corresponding LSP server string. You can query the names of all LSP servers in the lsp-bridge-single-lang-server-mode-list list. By default, this function returns nil.
2. lsp-bridge-single-lang-server-extension-list: Returns the server based on the file extension, for example, when opening a *.wxml file, we will use the wxml LSP server for completion.
3. lsp-bridge-single-lang-server-mode-list: Returns the corresponding server based on Emacs’s major-mode.

If you are writing JavaScript code, you may need to customize multiple server configurations:

1. lsp-bridge-get-multi-lang-server-by-project: A user-defined function that takes project-path and file-path as input parameters and returns the multiple server configuration names. You can search for them in the subdirectory lsp-bridge/multiserver.
2. lsp-bridge-multi-lang-server-extension-list: Returns multiple server configuration names based on the file extension. For example, when opening a *.vue file, we will use volar_emmet to simultaneously utilize volar and emmet-ls for completion.
3. lsp-bridge-multi-lang-server-mode-list: Returns the corresponding multiple server configuration names based on Emacs’s major-mode.

For example, we can enable the Deno LSP server for Deno scripts with the following configuration:

(setq lsp-bridge-get-multi-lang-server-by-project
      (lambda (project-path filepath)
        ;; If typescript file include deno.land url, then use Deno LSP server.
        (save-excursion
          (when (string-equal (file-name-extension filepath) "ts")
            (dolist (buf (buffer-list))
              (when (string-equal (buffer-file-name buf) filepath)
                (with-current-buffer buf
                  (goto-char (point-min))
                  (when (search-forward-regexp (regexp-quote "from \"https://deno.land") nil t)
                    (return "deno")))))))))

Copy the configuration files in lsp-bridge/langserver or lsp-bridge/multiserver to lsp-bridge-user-langserver-dir or lsp-bridge-user-multiserver-dir for customization. Lsp-bridge will prioritize reading the configuration files in lsp-bridge-user-langserver-dir or lsp-bridge-user-multiserver-dir.

We can set the value of lsp-bridge-user-langserver-dir or lsp-bridge-user-multiserver-dir before starting lsp-bridge-mode to achieve different project-specific configuration files.

(defun enable-lsp-bridge()
  (when-let* ((project (project-current))
              (project-root (nth 2 project)))
    (setq-local lsp-bridge-user-langserver-dir project-root
                lsp-bridge-user-multiserver-dir project-root))
  (lsp-bridge-mode))

1. Create a configuration file in the lsp-bridge/langserver directory. For example, pyright.json is the configuration file for the pyright server (use pyright_windows.json for Windows and pyright_darwin.json for macOS).
2. Add (mode . server_name) to the lsp-bridge-single-lang-server-mode-list option in the lsp-bridge.el file, for example, (python-mode . "pyright").
3. Add a new mode-hook to the lsp-bridge-default-mode-hooks option in the lsp-bridge.el file.
4. Add a new indentation variable to the lsp-bridge-formatting-indent-alist option in the lsp-bridge.el file.

We welcome patches to help us support more LSP servers. Thank you for your help!

You need to install the LSP server corresponding to each programming language, then lsp-bridge can provide code completion service.

If your language supports mixed multi-language servers, it is recommended to check the multi-language server definition under multiserver, and install multiple LSP servers to get a more complete experience. For example, for the Python language, according to the default pyright-background-analysis_ruff.json definition, you should install pyright and ruff.

The following is the framework of lsp-bridge:

The following is the directory structure of the lsp-bridge project:

Please read below articles first:

• LSP Specification
• The Design of lsp-bridge
• Why lsp-bridge not use capf
• lsp-bridge Wiki

Then turn on develop option lsp-bridge-enable-log and happy hacking! ;)

For some common problems, please read Wiki first.

Please use emacs -q and load a minimal setup with only lsp-bridge to verify that the bug is reproducible. If emacs -q works fine, probably something is wrong with your Emacs config.

If the problem still exists, please report it here with *lsp-bridge* buffer content, it contains many clues that can help us locate the problem faster.

• If you get a segfault error, please use the following way to collect crash information:

  1. Install gdb and turn on option lsp-bridge-enable-debug
  2. Use the command lsp-bridge-restart-process to restart the LSP-BRIDGE process
  3. Send issue with *lsp-bridge* buffer content when next crash

• If you get other errors, please use the following way to collection information:

  1. turn on option lsp-bridge-enable-log
  2. Use the command lsp-bridge-restart-process to restart the LSP-BRIDGE process
  3. Send issue with *lsp-bridge* buffer content