rs-web - Static Site Generator

A fast, opinionated static site generator built in Rust with support for:

• Markdown processing with syntax highlighting, external link handling
• Content encryption (full post or partial :::encrypted blocks)
• HTML content files with Tera templating support
• Link graph with backlinks and visualization (Obsidian-style)
• RSS feed generation with section filtering
• Parallel processing for fast builds

Installation

cargo install rs-web

Or with Nix:

nix run github:rslib/web#rs-web

Quick Start

# Build the site
rs-web build

# Build to custom output directory
rs-web build --output public

# Watch for changes and rebuild incrementally
rs-web build --watch

Logging

Control log verbosity with --debug, --log-level, or the RS_WEB_LOG_LEVEL environment variable.

# Enable debug logging (shorthand)
rs-web --debug build

# Set specific log level (trace, debug, info, warning, error)
rs-web --log-level trace build

# Use environment variable
RS_WEB_LOG_LEVEL=debug rs-web build

Priority order: --debug > --log-level > RS_WEB_LOG_LEVEL > default (warning)

Configuration

Configure via config.lua:

return {
  site = {
    title = "My Site",
    description = "Site description",
    base_url = "https://example.com",
    author = "Your Name",
  },

  build = {
    output_dir = "dist",
    minify_css = true,
  },

  -- Section configuration with custom sorting
  sections = {
    blog = {
      iterate = "files",  -- or "directories"
      sort_by = function(a, b)
        -- C-style comparator: return -1, 0, or 1
        if a.date < b.date then return -1
        elseif a.date > b.date then return 1
        else return 0 end
      end,
    },
  },

  -- Computed data available in templates as {{ computed.tags }}
  computed = {
    tags = function(sections)
      -- Process sections and return data for templates
      return { ... }
    end,
  },

  -- Generate dynamic pages (e.g., /tags/array/, /tags/string/)
  computed_pages = function(sections)
    return {
      { path = "/tags/array/", template = "tag.html", title = "Array", data = {...} },
    }
  end,

  -- Custom Tera filters: {{ value | my_filter }}
  filters = {
    shout = function(s) return s:upper() .. "!" end,
  },

  -- Build hooks
  hooks = {
    before_build = function()
      print("Starting build...")
    end,
    after_build = function()
      print("Build complete!")
    end,
  },
}

Lua Sandbox

By default, Lua file operations are sandboxed to the project directory (where config.lua is located). This prevents accidental or malicious access to files outside your project.

return {
  -- Sandbox is enabled by default. Set to false to allow access outside project directory.
  lua = {
    sandbox = false,  -- Disable sandbox (use with caution)
  },

  site = { ... },
}

When sandbox is enabled:

• File operations (read_file, write_file, load_json, etc.) only work within the project directory
• Attempting to access files outside returns an error with a helpful message
• Relative paths are resolved from the project root

Lua API Functions

Available in config.lua:

Note: All file operations respect the sandbox setting. Paths can be relative (resolved from project root) or absolute.

Async/Await Helpers

Coroutine-based cooperative multitasking with a cleaner API:

-- Create and run tasks
local task1 = async.task(function()
  local data = load_json("file1.json")
  async.yield()  -- cooperative yield
  return data
end)

-- Run single task to completion
local result = async.await(task1)

-- Run multiple tasks (interleaved execution)
local results = async.all({task1, task2, task3})

-- Race: return first completed
local winner, index = async.race({task1, task2})

Parallel Processing

True parallel execution using Rust's rayon thread pool:

-- Load multiple JSON files in parallel (I/O parallelism)
local configs = parallel.load_json({
  "content/problems/two-sum/config.json",
  "content/problems/reverse-string/config.json",
})

-- Read multiple files in parallel
local contents = parallel.read_files({"a.txt", "b.txt", "c.txt"})

-- Check multiple files exist in parallel
local exists = parallel.file_exists({"a.txt", "b.txt"})

-- Functional helpers (sequential but convenient)
local doubled = parallel.map(items, function(x) return x * 2 end)
local evens = parallel.filter(items, function(x) return x % 2 == 0 end)
local sum = parallel.reduce(items, 0, function(acc, x) return acc + x end)

Configuration Sections

Root Pages

Markdown files at the content root (besides the home page) are processed as standalone pages. For example, 404.md becomes 404.html:

---
title: "404 - Page Not Found"
template: "error.html"
---

# Page Not Found
The page you're looking for doesn't exist.

Default excluded files (disable with exclude_defaults = false):

• README.md, LICENSE.md, CHANGELOG.md, CONTRIBUTING.md, CODE_OF_CONDUCT.md
• Hidden files (starting with .)

Frontmatter

Post frontmatter options (YAML or TOML):

---
title: "Post Title"           # Required
description: "Description"    # Optional
date: 2024-01-15              # Optional (YAML date or string)
tags: ["tag1", "tag2"]        # Optional
draft: false                  # Optional (default: false, excluded from build)
image: "/static/post.png"     # Optional: OG image
template: "custom.html"       # Optional: Override template
slug: "custom-slug"           # Optional: Override URL slug
permalink: "/custom/url/"     # Optional: Full URL override
encrypted: false              # Optional: Encrypt entire post
password: "post-secret"       # Optional: Post-specific password
---

Content Types

Markdown Files (.md)

Standard markdown files processed through the markdown pipeline.

HTML Files (.html)

HTML files with Tera templating support. Can use extends, includes, and all Tera features:

+++
title = "Custom Page"
date = 2024-01-15
+++
{% extends "base.html" %}

{% block content %}
<div class="custom">
  <h1>{{ post.title }}</h1>
  <p>By {{ site.author }}</p>
</div>
{% endblock %}

Partial Encryption

Markdown

Use :::encrypted blocks for partial content encryption:

Public content here.

:::encrypted
This content is encrypted with the global/post password.
:::

:::encrypted password="custom"
This block has its own password.
:::

HTML

Use <encrypted> tags in HTML files:

<p>Public content here.</p>

<encrypted>
  <p>This content is encrypted.</p>
</encrypted>

<encrypted password="custom">
  <p>This block has its own password.</p>
</encrypted>

Template Variables

Home Template (home.html)

• site - Site config (title, description, base_url, author)
• page - Page info (title, description, url, image)
• sections - All sections with posts (sections.blog.posts)
• content - Rendered markdown content

Post Template (post.html)

• site - Site config
• post - Post info (title, url, date, tags, reading_time, etc.)
• page - Page info for head.html compatibility
• content - Rendered markdown content
• backlinks - Posts linking to this post (url, title, section)
• graph - Local graph data (nodes, edges) for visualization

Graph Template (graph.html)

• site - Site config
• page - Page info
• graph - Full graph data (nodes, edges)

License

MIT License. See LICENSE for details.