# rumdl - An extremely fast Markdown linter, written in Rust
<div align="center">
[](https://github.com/user/rumdl/actions)
[](https://opensource.org/licenses/MIT)
[](https://crates.io/crates/rumdl)
[](https://pypi.org/project/rumdl/)
## An extremely fast Markdown linter and formatter, written in Rust
</div>
## Table of Contents
- [rumdl - An extremely fast Markdown linter, written in Rust](#rumdl---an-extremely-fast-markdown-linter-written-in-rust)
- [Table of Contents](#table-of-contents)
- [Overview](#overview)
- [Installation](#installation)
- [Using Cargo (Rust)](#using-cargo-rust)
- [Using pip (Python)](#using-pip-python)
- [Download binary](#download-binary)
- [Usage](#usage)
- [Rules](#rules)
- [Command-line Interface](#command-line-interface)
- [Commands](#commands)
- [Options](#options)
- [Configuration](#configuration)
- [Output Style](#output-style)
- [Output Format](#output-format)
- [Development](#development)
- [Prerequisites](#prerequisites)
- [Building](#building)
- [Testing](#testing)
- [License](#license)
## Overview
rumdl is a lightning-fast Markdown linter and fixer that helps ensure consistency and best practices in your Markdown files. It offers:
- ⚡️ **10-50x faster** than other Markdown linters
- 🔍 **50+ lint rules** covering common Markdown issues
- 🛠️ **Automatic fixing** with `--fix` for most rules
- 📦 **Zero dependencies** - single binary with no runtime requirements
- 🔧 **Highly configurable** with TOML-based config files
- 🌐 **Multiple installation options** - Rust, Python, standalone binaries
- 📏 **Modern CLI** with detailed error reporting
- 🔄 **CI/CD friendly** with non-zero exit code on errors
## Installation
Choose the installation method that works best for you:
### Using Cargo (Rust)
```bash
cargo install rumdl
```
### Using pip (Python)
```bash
pip install rumdl
```
### Download binary
```bash
# Linux/macOS
curl -LsSf https://github.com/user/rumdl/releases/latest/download/rumdl-linux-x86_64.tar.gz | tar xzf - -C /usr/local/bin
# Windows PowerShell
Invoke-WebRequest -Uri "https://github.com/user/rumdl/releases/latest/download/rumdl-windows-x86_64.zip" -OutFile "rumdl.zip"
Expand-Archive -Path "rumdl.zip" -DestinationPath "$env:USERPROFILE\.rumdl"
```
## Usage
Getting started with rumdl is simple:
```bash
# Check a single file
rumdl README.md
# Check all Markdown files in current directory and subdirectories
rumdl .
# Automatically fix issues
rumdl --fix README.md
# Create a default configuration file
rumdl init
```
Common usage examples:
```bash
# Check with custom configuration
rumdl --config my-config.toml docs/
# Disable specific rules
rumdl --disable MD013,MD033 README.md
# Enable only specific rules
rumdl --enable MD001,MD003 README.md
# Exclude specific files/directories
rumdl --exclude "node_modules,dist" .
# Include only specific files/directories
rumdl --include "docs/*.md,README.md" .
# Combine include and exclude patterns
rumdl --include "docs/**/*.md" --exclude "docs/temp,docs/drafts" .
```
## Rules
rumdl implements over 50 lint rules for Markdown files. Here are some key rule categories:
| **Headings** | Proper heading structure and formatting | MD001, MD002, MD003 |
| **Lists** | Consistent list formatting and structure | MD004, MD005, MD007 |
| **Whitespace** | Proper spacing and line length | MD009, MD010, MD012 |
| **Code** | Code block formatting and language tags | MD040, MD046, MD048 |
| **Links** | Proper link and reference formatting | MD034, MD039, MD042 |
| **Images** | Image alt text and references | MD045, MD052 |
| **Style** | Consistent style across document | MD031, MD032, MD035 |
For a complete list of rules and their descriptions, see our [documentation](docs/RULES.md) or run:
```bash
rumdl --list-rules
```
## Command-line Interface
```bash
rumdl [options] [file or directory...]
rumdl <command> [options]
```
### Commands
- `init`: Create a default `.rumdl.toml` configuration file in the current directory
### Options
- `-c, --config <file>`: Use custom configuration file
- `-f, --fix`: Automatically fix issues where possible
- `-l, --list-rules`: List all available rules
- `-d, --disable <rules>`: Disable specific rules (comma-separated)
- `-e, --enable <rules>`: Enable only specific rules (comma-separated)
- `--exclude <patterns>`: Exclude specific files or directories (comma-separated glob patterns)
- `--include <patterns>`: Include only specific files or directories (comma-separated glob patterns)
- `--respect-gitignore`: Respect .gitignore files when scanning directories
- `-v, --verbose`: Show detailed output
## Configuration
rumdl can be configured using a TOML configuration file. By default, it looks for `rumdl.toml` or `.rumdl.toml` in the current directory.
You can create a default configuration file using the `init` command:
```bash
rumdl init
```
This will create a `.rumdl.toml` file in the current directory with default settings that you can customize.
Example configuration file:
```toml
# Global configuration options
[global]
# List of rules to disable
disable = ["MD013", "MD033"]
# List of rules to enable exclusively (if provided, only these rules will run)
# enable = ["MD001", "MD003", "MD004"]
# List of file/directory patterns to include for linting (if provided, only these will be linted)
include = [
# Documentation files
"docs/**/*.md",
"README.md",
"CONTRIBUTING.md",
]
# List of file/directory patterns to exclude from linting
exclude = [
# Common directories to exclude
".git",
".github",
"node_modules",
"vendor",
"dist",
"build",
# Specific files or patterns
"CHANGELOG.md",
"LICENSE.md",
"generated/*.md",
"**/temp_*.md",
]
# Whether to respect .gitignore files when scanning directories
respect_gitignore = false
# Rule-specific configurations
[MD002]
level = 1 # Expected level for first heading
[MD003]
style = "atx" # Heading style (atx, atx_closed, setext)
```
## Output Style
rumdl produces clean, colorized output similar to modern linting tools:
```text
README.md:12:1: [MD022] Headings should be surrounded by blank lines [*]
README.md:24:5: [MD037] Spaces inside emphasis markers: "* incorrect *" [*]
README.md:31:76: [MD013] Line length exceeds 80 characters
README.md:42:3: [MD010] Hard tabs found, use spaces instead [*]
```
When running with `--fix`, rumdl shows which issues were fixed:
```text
README.md:12:1: [MD022] Headings should be surrounded by blank lines [fixed]
README.md:24:5: [MD037] Spaces inside emphasis markers: "* incorrect *" [fixed]
README.md:42:3: [MD010] Hard tabs found, use spaces instead [fixed]
Fixed 3 issues in 1 file
```
For a more detailed view, use the `--verbose` option:
```text
✓ No issues found in CONTRIBUTING.md
README.md:12:1: [MD022] Headings should be surrounded by blank lines [*]
README.md:24:5: [MD037] Spaces inside emphasis markers: "* incorrect *" [*]
README.md:42:3: [MD010] Hard tabs found, use spaces instead [*]
Found 3 issues in 1 file (2 files checked)
Run with `--fix` to automatically fix issues
```
### Output Format
rumdl uses a consistent output format for all issues:
```text
{file}:{line}:{column}: [{rule*id}] {message} [{fix*indicator}]
```
The output is colorized by default:
- Filenames appear in blue and underlined
- Line and column numbers appear in cyan
- Rule IDs appear in yellow
- Error messages appear in white
- Fixable issues are marked with `[*]` in green
- Fixed issues are marked with `[fixed]` in green
## Development
### Prerequisites
- Rust 1.70 or higher
- Make (for development commands)
### Building
```bash
make build
```
### Testing
```bash
make test
```
## License
MIT License