Fast sites. Safe builds. Flexible setup.

A fast, configurable static site generator powered by Deno.

Sponsored by Tuta

Steno supports both configured projects and an optional zero-config mode. Use a configuration file for structured content, themes, plugins, and project-wide settings, or build a single Markdown file without any setup. Builds are incremental and transactional, so failed builds preserve the last successful output.

Plugins can run in isolated, deny-by-default Deno subprocesses with explicit permissions, deadlines, memory ceilings, output limits, cancellation, and crash containment. Trusted plugins remain available when full in-process access is required.

Quick Start

Create a Configured Project

The interactive initializer creates a configured project with your selected theme, optional plugins, structured content, and reusable tasks:

deno create jsr:@steno/init@0.10.0

The generated project is ready to run:

deno task dev
deno task build

Use Zero-Config Mode

For a single page or a small experiment, create my-site/content/index.md:

# Hello from Steno

From my-site, build it:

deno x jsr:@steno/steno@0.10.0 build

Steno detects the single Markdown file, applies the default theme, and writes:

dist/
└── index.html

Zero-config mode is optional. Add content/.steno/config.yml whenever the site needs explicit project settings.

Why Steno

• Flexible setup: Use a full configuration file or optionally build from one Markdown file without configuration.
• Transactional output: A failed build preserves the last successful site.
• Incremental compilation: Unchanged pages reuse cached output.
• Isolated plugins: Deny filesystem, environment, network, subprocess, and FFI access until each capability is explicitly granted.
• Tau templates: Use expressions, components, loops, conditions, includes, filters, and contextual escaping.
• Flexible themes: Load bundled, local, JSR, npm, or HTTPS themes.
• Structured content: Use collections, data files, drafts, redirects, custom routes, and YAML or TOML frontmatter.
• Development server: Watch files and reload the browser as content changes.
• Real-world testing: Exercise complete sites and official plugins in CI, with additional cross-platform coverage on Linux, macOS, and Windows.

Structured Project

A configured Steno project keeps content and configuration together:

content/
├── .steno/
│   └── config.yml
└── index.md

Configure the site in content/.steno/config.yml:

title: "My Steno Site"
description: "A site built with Steno"
author: "Your Name"
contentDir: "content"
output: "dist"

custom:
  shortUrls: true
  theme: "jsr:@steno/theme-minimal@^0.10.0"

Add frontmatter to content/index.md when the page needs metadata or a specific layout:

---
title: Home
layout: layout
---

# Hello World

Welcome to a site powered by Steno and Tau.

Run the development server:

deno x jsr:@steno/steno@0.10.0 dev

Create production output:

deno x jsr:@steno/steno@0.10.0 build

Themes and Tau

Themes can live in a local directory or be loaded from JSR, npm, or HTTPS. A theme contains metadata, assets, layouts, and optional components:

themes/minimalist/
├── theme.yaml
├── assets/
│   └── style.css
├── components/
│   └── header.tau
└── layouts/
    └── layout.tau

Tau is Steno's compiled template language:

{#if title}
  <Header />
{/if}

<main class="prose">
  {@html content}
</main>

{#each tags as tag}
  <span class="badge">{tag}</span>
{/each}

Regular interpolated expressions are HTML-escaped. {@html expression} deliberately emits raw HTML and should only receive trusted or sanitized content. See the Tau syntax specification for its complete semantics and security rules.

Plugins and Isolation

Plugins can transform Markdown tokens and HTML, or run before and after builds. Pin plugin versions so builds remain reproducible:

plugins:
  - package: "jsr:@steno/plugin-shiki@1.0.0"
    mode: isolated
    options:
      theme: github-dark

  - package: "jsr:@steno/plugin-seo@0.7.0"
    mode: trusted
    options:
      siteUrl: "https://example.com"

Plugins configured with mode: isolated execute in a separate Deno process. Runtime capabilities are denied unless the plugin entry grants them explicitly. Isolation also enforces hook deadlines, bounded messages, a heap ceiling, cancellation, and crash containment.

String plugin entries and plugins configured with mode: trusted run in-process with Steno's permissions. Themes and theme-provided plugins are also trusted. Only install trusted extensions from sources you have reviewed.

Top-level plugin sources can be restricted independently of execution mode:

custom:
  pluginSourcePolicy:
    allowLocal: false
    allowRemoteHttp: false
    allowNodeBuiltins: false
    allowThemePlugins: true

The source policy validates the configured top-level specifier. See the plugin sandbox threat model for permission examples, transitive-import behavior, integrity checks, and current limitations.

Performance

Steno benchmarks cold, unchanged warm, and atomic incremental builds. The suite also includes a 4,000-page fixture, frontmatter parsing, the Markdown-to-Tau pipeline, and Tau rendering at multiple scales.

Performance varies by machine and Deno version. The benchmark report records the test environment, averages, and tail latency instead of presenting one result as universal.

deno task bench
deno task bench:check
deno task bench:report

CLI

steno [command] [options]

Command	Description
build	Build the site. This is the default command.
dev	Build, watch files, and serve with live reload.
preview	Serve an existing production build without watching.
doctor	Check the project for common configuration and security issues.
help	Print CLI usage.

Option	Description
-c, --config <path>	Use a specific configuration file.
-p, --port <number>	Select the preview port. The default is 4173.
-h, --help	Show CLI usage.

The default configuration path is content/.steno/config.yml. See the doctor guide for project diagnostics.

Documentation

• Getting started
• Configuration reference
• Content and collections
• Tau syntax specification
• Plugin development
• Plugin sandbox and threat model
• Theme development
• Theme specification
• API reference
• Atomic build guarantees
• Performance methodology

Contributing

The repository includes unit, conformance, security, real-site, ecosystem, and performance tests:

deno task dev
deno task test
deno task test:sites
deno task test:ecosystem
deno task check
deno task bench:check

Read CONTRIBUTING.md before submitting a change.

Sponsors

License

MIT © Gabriel Cozma and contributors. See LICENSE.txt for details.