Rustyll gives you a lot of flexibility to customize how it builds your site. These options can either be specified in a _config.yml file placed in your site’s root directory, or as flags for the rustyll executable in the terminal.

Default Configuration

Rustyll ships with sensible defaults for most configuration options. The default configuration is:

# Where things are
source:          .
destination:     ./_site
collections_dir: .
plugins_dir:     _plugins
layouts_dir:     _layouts
data_dir:        _data
includes_dir:    _includes

# Handling Reading
include:         [".htaccess"]
exclude:         ["Cargo.toml", "Cargo.lock", "node_modules/", "vendor/bundle/", "vendor/cache/", "vendor/gems/", "vendor/ruby/"]
keep_files:      [".git", ".svn"]
encoding:        "utf-8"
markdown_ext:    "markdown,mkdown,mkdn,mkd,md"
strict_front_matter: false

# Plugins
plugins: []

# Conversion
markdown:    comrak
highlighter: rouge

# Serving
port: 4000
host: 127.0.0.1
baseurl: ""
show_dir_listing: false

# Output
permalink:     date
pagination:    false
timezone:      null

# Rustyll Performance
threads:       auto
incremental:   false
parallel:      true
cache:
  enabled:     true
  strategy:    normal

Performance Configuration

Rustyll offers extensive performance configuration options not available in Jekyll:

# Multi-threading options
threads: auto  # Use all available CPU cores, or specify a number

# Parallel processing
parallel:
  enabled: true
  markdown: true
  sass: true
  liquid: true
  layouts: true
  collections: true
  max_threads_per_task: 4

# Caching configuration
cache:
  enabled: true
  strategy: aggressive  # Options: conservative, normal, aggressive
  expiry: 3600          # Seconds to keep cache valid
  liquid: true
  markdown: true
  partials: true
  
# Memory optimizations
memory:
  optimize: true
  limit: 0              # Memory limit in MB (0 = unlimited)
  preload_templates: true
  
# Incremental building
incremental:
  enabled: true
  safe_mode: false      # Stricter dependency tracking
  
# Build prioritization
priority:
  homepage: 1           # Lower numbers = higher priority
  posts: 2
  pages: 3

Build Command Options

You can either use flags on the command line or set them in your _config.yml file. Command line options override configuration from your config file.

Customizing Build Options

# Build your site
rustyll build --output _mysite

# Build with watch mode for faster rebuilds
rustyll build --watch

# Build with multiple threads for blazing fast performance
rustyll build --threads 8

Configuring Parallel Builds

Rustyll’s parallel build system can be configured for optimal performance:

# _config.yml

# Configure parallel processing
parallel:
  enabled: true            # Master switch for parallel processing
  strategy: optimistic     # How to handle dependencies (conservative, balanced, optimistic)
  
  # Control specific components
  markdown: true           # Process markdown in parallel
  collections: true        # Process collections in parallel
  assets: true             # Process assets in parallel
  
  # Fine-tuned control
  max_threads_per_task: 4  # Maximum threads per task type
  min_items_per_thread: 5  # Only parallelize when enough items exist
  
  # Advanced settings
  thread_priority:         # Set thread priorities (1-10, lower = higher priority)
    markdown: 1
    collections: 2
    assets: 3
    
  # Dynamic scaling
  auto_scale: true         # Dynamically adjust thread count based on system load

Jekyll Compatibility

Rustyll is designed to be a drop-in replacement for Jekyll, so all Jekyll configuration options are supported. However, Rustyll adds many performance-focused options that aren’t available in Jekyll.

Learn More

For more information, check out the Configuration documentation:

• Default configuration
• Front matter defaults
• Environments
• Markdown options
• Liquid options
• Parallel processing
• Cache configuration
• Memory optimization