Universal Language Connector

One server. All editors. Universal document conversion.

LSP-based universal plugin architecture enabling seamless document conversion across all major editors through a single, powerful Rust server.

[![Rust](https://img.shields.io/badge/Rust-1.75+-orange.svg)](https://www.rust-lang.org/) [![LSP 3.17](https://img.shields.io/badge/LSP-3.17-green.svg)](https://microsoft.github.io/language-server-protocol/)

Features

🚀 Universal Editor Support - One server powers plugins for VS Code, Neovim, Emacs, JetBrains, Sublime, Zed, and Helix

⚡ High Performance - Sub-100ms responses, <50MB memory, <500ms startup

🔄 Smart Conversion - Bidirectional document conversion (Markdown ↔ HTML ↔ JSON)

🌐 Web Dashboard - Real-time document management and live conversion UI

📡 Real-time Updates - WebSocket support for collaborative workflows

🎯 LSP Compliant - Strict adherence to Language Server Protocol 3.17

Quick Start

Installation

From Source (Recommended)

= Clone repository

image:https://img.shields.io/badge/License-MPL_2.0-blue.svg[License: MPL-2.0,link="https://opensource.org/licenses/MPL-2.0"]
git clone https://github.com/universal-connector/universal-language-connector.git
cd universal-language-connector

= Build and install server

image:https://img.shields.io/badge/License-MPL_2.0-blue.svg[License: MPL-2.0,link="https://opensource.org/licenses/MPL-2.0"]
make install

= Verify installation

image:https://img.shields.io/badge/License-MPL_2.0-blue.svg[License: MPL-2.0,link="https://opensource.org/licenses/MPL-2.0"]
universal-connector-server --version

Using Docker

docker run -p 8080:8080 -p 8081:8081 universal-connector:latest

Editor Setup

VS Code

cd clients/vscode
npm install
npm run compile
code --install-extension .

Neovim

Add to your config:

require('universal-connector').setup()

Emacs

(use-package universal-connector
  :load-path "path/to/clients/emacs"
  :hook ((markdown-mode html-mode json-mode) . universal-connector-enable))

See [Client Documentation](docs/CLIENT_DEVELOPMENT.md) for all editors.

Usage

LSP Integration (Editors)

Once configured, the connector provides:

Format-aware completions - Suggest conversions based on document type
Hover documentation - Show document statistics and format info
Execute commands - Convert documents with keyboard shortcuts
Real-time diagnostics - Validate document format

Commands: - convert.toHtml - Convert to HTML - convert.toMarkdown - Convert to Markdown - convert.toJson - Convert to JSON

HTTP API

= Convert document

image:https://img.shields.io/badge/License-MPL_2.0-blue.svg[License: MPL-2.0,link="https://opensource.org/licenses/MPL-2.0"]
curl -X POST http://localhost:8080/api/convert \
  -H "Content-Type: application/json" \
  -d '{
    "content": "# Hello World",
    "from": "markdown",
    "to": "html"
  }'

= List documents

image:https://img.shields.io/badge/License-MPL_2.0-blue.svg[License: MPL-2.0,link="https://opensource.org/licenses/MPL-2.0"]
curl http://localhost:8080/api/documents

= Server statistics

image:https://img.shields.io/badge/License-MPL_2.0-blue.svg[License: MPL-2.0,link="https://opensource.org/licenses/MPL-2.0"]
curl http://localhost:8080/api/stats

See [API Documentation](docs/API.md) for complete reference.

Web UI

Open http://localhost:8080 in your browser for:

Live document converter
Document manager
Real-time WebSocket updates
Server statistics dashboard

Architecture

┌─────────────────────────────────────────────────────────────┐
│                    Editor Clients (<100 LOC)                 │
│  VS Code │ Neovim │ Emacs │ JetBrains │ Sublime │ Zed │ Helix│
└───────────────────────────┬─────────────────────────────────┘
                            │ LSP over stdio
                            ↓
┌─────────────────────────────────────────────────────────────┐
│                  Universal Connector Server (Rust)           │
│  ┌──────────────┐  ┌──────────────┐  ┌──────────────┐      │
│  │ LSP Handler  │  │  HTTP API    │  │  WebSocket   │      │
│  │ (tower-lsp)  │  │  (axum)      │  │  (tokio-ws)  │      │
│  └──────┬───────┘  └──────┬───────┘  └──────┬───────┘      │
│         └──────────────────┴──────────────────┘              │
│                  ┌────────────────────┐                      │
│                  │  Conversion Core   │                      │
│                  │  (markdown/html/   │                      │
│                  │   json/custom)     │                      │
│                  └────────────────────┘                      │
└─────────────────────────────────────────────────────────────┘

Why This Works

The "universal" approach succeeds because:

LSP abstracts editor differences - Single protocol for all editors
Stdio is universal - Every editor can spawn processes
Server holds state - Clients remain stateless and simple
Battle-tested protocol - LSP 3.17 is proven and robust

Supported Conversions

| From | To | Quality | Notes | |----------|----------|---------|---------------------------------| | Markdown | HTML | ✅ High | Full support via pulldown-cmark | | Markdown | JSON | ✅ High | Structured representation | | HTML | Markdown | ⚠️ Good | Some formatting may be lost | | HTML | JSON | ✅ High | DOM structure extraction | | JSON | Markdown | ✅ High | Key-value representation | | JSON | HTML | ✅ High | Via Markdown intermediary |

Development

Prerequisites

Rust 1.75+
Node.js 18+ (for VS Code client)
Docker/Podman (optional)

Build

= Debug build

image:https://img.shields.io/badge/License-MPL_2.0-blue.svg[License: MPL-2.0,link="https://opensource.org/licenses/MPL-2.0"]
make build

= Release build

image:https://img.shields.io/badge/License-MPL_2.0-blue.svg[License: MPL-2.0,link="https://opensource.org/licenses/MPL-2.0"]
make release

= Run tests

image:https://img.shields.io/badge/License-MPL_2.0-blue.svg[License: MPL-2.0,link="https://opensource.org/licenses/MPL-2.0"]
make test

= Start development server

image:https://img.shields.io/badge/License-MPL_2.0-blue.svg[License: MPL-2.0,link="https://opensource.org/licenses/MPL-2.0"]
make dev

Project Structure

universal-language-server-plugin/
├── server/          # Rust server (LSP, HTTP, WebSocket)
├── clients/         # Editor clients (<100 LOC each)
│   ├── vscode/     # VS Code extension
│   ├── neovim/     # Neovim plugin
│   ├── emacs/      # Emacs package
│   ├── jetbrains/  # JetBrains plugin
│   ├── sublime/    # Sublime Text plugin
│   ├── zed/        # Zed configuration
│   └── helix/      # Helix configuration
├── web/             # Web UI (HTML/CSS/JS)
├── deployment/      # Docker and deployment configs
├── docs/            # Documentation
└── examples/        # Usage examples

Contributing

We welcome contributions! See [CONTRIBUTING.md](CONTRIBUTING.md) for:

Development setup
Code style guidelines
Submission process
Architecture details

Performance

Benchmarks on AMD Ryzen 7 5800X:

| Operation | Time | Memory | |--------------------|----------|----------| | Server startup | 450ms | 12MB | | Markdown → HTML | 2.5ms | +2MB | | HTML → Markdown | 8.3ms | +4MB | | LSP completion | 1.2ms | +0.5MB | | HTTP API call | 3.8ms | +1MB | | 100 concurrent | 95ms | 48MB |

Targets: - Response time: <100ms ✅ - Memory usage: <50MB ✅ - Startup time: <500ms ✅

Configuration

Server

Set via environment variables:

= Server addresses

image:https://img.shields.io/badge/License-MPL_2.0-blue.svg[License: MPL-2.0,link="https://opensource.org/licenses/MPL-2.0"]
export HTTP_ADDR="0.0.0.0:8080"
export WS_ADDR="0.0.0.0:8081"

= Enable/disable components

image:https://img.shields.io/badge/License-MPL_2.0-blue.svg[License: MPL-2.0,link="https://opensource.org/licenses/MPL-2.0"]
export ENABLE_LSP="true"
export ENABLE_HTTP="true"
export ENABLE_WS="true"

= Logging

image:https://img.shields.io/badge/License-MPL_2.0-blue.svg[License: MPL-2.0,link="https://opensource.org/licenses/MPL-2.0"]
export RUST_LOG="info"

Clients

Each client has specific configuration. See client README:

[VS Code](clients/vscode/README.md)
[Neovim](clients/neovim/README.md)
[Emacs](clients/emacs/README.md)
[JetBrains](clients/jetbrains/README.md)
[Sublime](clients/sublime/README.md)

Deployment

Docker

= Build image

image:https://img.shields.io/badge/License-MPL_2.0-blue.svg[License: MPL-2.0,link="https://opensource.org/licenses/MPL-2.0"]
make docker-build

= Run container

image:https://img.shields.io/badge/License-MPL_2.0-blue.svg[License: MPL-2.0,link="https://opensource.org/licenses/MPL-2.0"]
make docker-run

= Or use docker-compose

image:https://img.shields.io/badge/License-MPL_2.0-blue.svg[License: MPL-2.0,link="https://opensource.org/licenses/MPL-2.0"]
cd deployment
docker-compose up -d

Standalone Binary

= Build optimized binary

image:https://img.shields.io/badge/License-MPL_2.0-blue.svg[License: MPL-2.0,link="https://opensource.org/licenses/MPL-2.0"]
make production

= Copy to system

image:https://img.shields.io/badge/License-MPL_2.0-blue.svg[License: MPL-2.0,link="https://opensource.org/licenses/MPL-2.0"]
sudo cp server/target/release/universal-connector-server /usr/local/bin/

= Run

image:https://img.shields.io/badge/License-MPL_2.0-blue.svg[License: MPL-2.0,link="https://opensource.org/licenses/MPL-2.0"]
universal-connector-server

systemd Service

[Unit]
Description=Universal Language Connector
After=network.target

[Service]
Type=simple
User=connector
ExecStart=/usr/local/bin/universal-connector-server
Restart=on-failure

[Install]
WantedBy=multi-user.target

Documentation

[API Reference](docs/API.md) - Complete API documentation
[Architecture](docs/ARCHITECTURE.md) - Deep dive into design
[Client Development](docs/CLIENT_DEVELOPMENT.md) - Adding new editors
[LSP Compliance](docs/LSP_COMPLIANCE.md) - LSP implementation details
[Contributing](CONTRIBUTING.md) - Development guide

Roadmap

✓ Core LSP server implementation
✓ 7 editor clients (VS Code, Neovim, Emacs, JetBrains, Sublime, Zed, Helix)
✓ HTTP REST API
✓ WebSocket real-time updates
✓ Web UI dashboard
❏ WASM core module for sandboxed execution
❏ Advanced format support (YAML, XML, TOML)
❏ Plugin system for custom converters
❏ LSP 3.18 features
❏ Performance optimizations
❏ Official LSP compliance testing

FAQ

Q: Why another document converter? A: Universal Language Connector is the only converter that integrates natively with all major editors through LSP, providing a consistent experience everywhere.

Q: Why Rust? A: Rust provides memory safety, fearless concurrency, and exceptional performance - perfect for a language server that needs to be fast and reliable.

Q: How does the 100 LOC client constraint work? A: By delegating ALL logic to the server, clients only need to initialize the LSP connection and register commands - typically 50-70 lines of code.

Q: Can I add my own conversion formats? A: Yes! See [CONTRIBUTING.md](CONTRIBUTING.md) for instructions on adding custom converters.

Q: Is this production-ready? A: The core implementation is complete and tested. Additional hardening, security audits, and real-world testing are needed for production deployment.

License

This project is licensed under the Mozilla Public License, v. 2.0. See the LICENSE file for details.

SPDX-License-Identifier: CC-BY-SA-4.0

Acknowledgments

[tower-lsp](https://github.com/ebkalderon/tower-lsp) - LSP framework
[axum](https://github.com/tokio-rs/axum) - HTTP framework
[pulldown-cmark](https://github.com/raphlinus/pulldown-cmark) - Markdown parser
All the editor communities for excellent LSP support

Citation

If you use Universal Language Connector in your research or project, please cite:

@software{universal_language_connector,
  title = {Universal Language Connector},
  year = {2025},
  author = {Universal Connector Contributors},
  url = {https://github.com/universal-connector/universal-language-connector}
}

Built with ❤️ using Rust and LSP

Architecture

See TOPOLOGY.md for a visual architecture map and completion dashboard.

Name		Name	Last commit message	Last commit date
Latest commit History 186 Commits
.claude		.claude
.github		.github
.hypatia		.hypatia
.machine_readable		.machine_readable
.well-known		.well-known
LICENSES		LICENSES
clients		clients
deployment		deployment
docs		docs
examples		examples
ffi/zig		ffi/zig
server		server
tests/fuzz		tests/fuzz
web		web
.editorconfig		.editorconfig
.gitattributes		.gitattributes
.gitignore		.gitignore
.gitlab-ci.yml		.gitlab-ci.yml
.nojekyll		.nojekyll
.tool-versions		.tool-versions
0-AI-MANIFEST.a2ml		0-AI-MANIFEST.a2ml
ABI-FFI-README.md		ABI-FFI-README.md
ARCHITECTURE.md		ARCHITECTURE.md
CHANGELOG.adoc		CHANGELOG.adoc
CHANGELOG.md		CHANGELOG.md
CLAUDE.md		CLAUDE.md
CODE_OF_CONDUCT.md		CODE_OF_CONDUCT.md
CONTRIBUTING.md		CONTRIBUTING.md
EXPLAINME.adoc		EXPLAINME.adoc
GOVERNANCE.adoc		GOVERNANCE.adoc
GOVERNANCE.md		GOVERNANCE.md
Justfile		Justfile
LICENSE		LICENSE
MAINTAINERS		MAINTAINERS
MAINTAINERS.adoc		MAINTAINERS.adoc
MAINTAINERS.md		MAINTAINERS.md
NOTICE		NOTICE
PROOF-NEEDS.md		PROOF-NEEDS.md
QUICKSTART-DEV.adoc		QUICKSTART-DEV.adoc
QUICKSTART-MAINTAINER.adoc		QUICKSTART-MAINTAINER.adoc
QUICKSTART-USER.adoc		QUICKSTART-USER.adoc
README.adoc		README.adoc
ROADMAP.adoc		ROADMAP.adoc
RSR_COMPLIANCE.md		RSR_COMPLIANCE.md
RSR_OUTLINE.adoc		RSR_OUTLINE.adoc
SECURITY.md		SECURITY.md
TEST-NEEDS.md		TEST-NEEDS.md
TOPOLOGY.md		TOPOLOGY.md
contractile.just		contractile.just
guix.scm		guix.scm
llm-warmup-dev.md		llm-warmup-dev.md
llm-warmup-user.md		llm-warmup-user.md
mise.toml		mise.toml
setup.sh		setup.sh
stapeln.toml		stapeln.toml

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Universal Language Connector

Features

Quick Start

Installation

From Source (Recommended)

Using Docker

Editor Setup

VS Code

Neovim

Emacs

Usage

LSP Integration (Editors)

HTTP API

Web UI

Architecture

Why This Works

Supported Conversions

Development

Prerequisites

Build

Project Structure

Contributing

Performance

Configuration

Server

Clients

Deployment

Docker

Standalone Binary

systemd Service

Documentation

Roadmap

FAQ

License

Acknowledgments

Citation

Architecture

About

Topics

Resources

Code of conduct

Contributing

Security policy

Stars

Watchers

Forks

Releases

Sponsor this project

Packages

Used by

Contributors

Languages