💩 Poops

Straightforward, no-bullshit bundler for the web.

When your day is long

And the night, the night is yours alone

When you're sure you've had enough

Of these bundlers, well hang on

Don't let yourself go

'Cause everybody poops

Everybody poops sometimes

R.E.M. - Everybody Poops :poop:

Intuitive with a minimal learning curve and minimal docs, utilizing the most efficient transpilers and compilers available (like dart-sass and esbuild) Poops aims to be the simplest bundler option there is. If it's not, please do contribute so we can make it so! 🙏 All ideas and contributions are welcome.

It uses a simple config file where you define your input and output paths and it poops out your bundled files. Simple as that.

Table of Contents

• Features
• Quick Start
• Configuration
  • Scripts
    • JSX/TSX (React) Example
  • Reactor (React Pre-rendering)
  • Styles
    • Design Tokens
  • PostCSS (optional)
    • Tailwind CSS Example
  • Markups
    • Nunjucks vs Liquid
    • Custom Engines
    • Collections & Pagination
    • Custom Tags
      • image
      • googleFonts
      • highlight
    • Custom Filters
    • Search Index, Sitemap & Navigation
  • Images (optional)
  • Copy
  • Banner (optional)
  • Local Server (optional)
  • Live Reload (optional)
  • Watch (optional)
  • Include Paths (optional)
• Why?

Features

• Bundles SCSS/SASS to CSS
• Uses dart-sass for SCSS/SASS bundling
• Design token support — import JSON tokens (W3C DTCG & Style Dictionary) as SCSS variables or maps
• PostCSS pipeline — use any PostCSS plugin including Tailwind CSS
• Bundles JS/TS/JSX/TSX to IIFE/ESM/CJS
• Uses esbuild for bundling and transpiling JS/TS/JSX/TSX to IIFE/ESM/CJS
• React pre-rendering (Reactor) — renders React components to HTML at build time for static sites with optional hydration
• Optional JS and CSS minification using esbuild
• Can produce minified code simultaneously with non-minified code! (cause I always forget to minify my code for production)
• Supports source maps only for non minified - non production code (optional)
• Supports multiple input and output paths
• Resolves node modules
• Can add a templatable banner to output files (optional)
• Static site generation with swappable template engines: Nunjucks (default) or Liquid — with blogging option (optional)
• Has a configurable local server (optional)
• Rebuilds on file changes (optional)
• Live reloads on file changes (optional)

Quick Start

For a superfast start, you can use the Poops template repository: 💩🌪️Shitstorm

You can install Poops globally:

npm i -g poops

or locally:

npm i -D poops

If you have installed Poops globally, create a poops.json or 💩.json configuration file in the project root (see Configuration on how to configure) and run:

poops or 💩

or pass a custom config. This is useful when you have multiple environments:

poops yourAwesomeConfig.json or 💩 yourAwesomeConfig.json

CLI Options:

| Flag | Short | Description | | ---------------------------- | ----- | ---------------------------------------------------- | | --build | -b | Build the project and exit | | --config <path> | -c | Specify the config file | | --port <number> | -p | Specify the server port, overrides config | | --livereload-port <number> | -l | Specify the livereload port, overrides config | | --base-url <path> | -u | Set the base URL prefix for markup, overrides config |

The --base-url flag is particularly useful for CI/CD pipelines where the deploy path may differ per environment:

poops --build --base-url /blog

If you have installed Poops locally you can run it with npx poops or npx 💩 or add a script to your package.json:

{
  "scripts": {
    "build": "npx poops" // or "npx 💩"
  }
}

Configuration

Configuring Poops is simple 😌. Let's presume that we have a example/src/scss and example/src/js directories and we want to bundle the files into example/dist/css and example/dist/js. If you also have markup files, you can use Nunjucks (default) or Liquid templating engine to generate HTML files from your templates. Let's presume that we have a example/src/markup directory and we want to generate HTML files in the root of the your directory.

Just create a poops.json file in the root of your project and add the following (you can see this sample config in this repo's root):

{
  "scripts": [
    {
      "in": "example/src/js/main.ts",
      "out": "example/dist/js/scripts.js",
      "options": {
        "sourcemap": true,
        "minify": true,
        "justMinified": false,
        "format": "iife",
        "target": "es2019"
      }
    }
  ],
  "reactor": [
    {
      "component": "example/src/js/App.jsx",
      "inject": "app_html",
      "in": "example/src/js/app-hydrate.jsx",
      "out": "example/dist/js/app-hydrate.js",
      "options": {
        "minify": true,
        "target": "es2019"
      }
    }
  ],
  "styles": [
    {
      "in": "example/src/scss/index.scss",
      "out": "example/dist/css/styles.css",
      "options": {
        "sourcemap": true,
        "minify": true,
        "justMinified": false
      }
    }
  ],
  "markup": {
    "engine": "nunjucks",
    "in": "example/src/markup",
    "out": "/",
    "site": {
      "title": "Poops",
      "description": "A super simple bundler for simple web projects."
    },
    "data": ["data/links.json", "data/poops.yaml"],
    "includePaths": ["_layouts", "_partials"]
  },
  "copy": [
    {
      "in": "example/src/static",
      "out": "example/dist"
    }
  ],
  "banner": "/* {{ name }} v{{ version }} | {{ homepage }} | {{ license }} License */",
  "serve": {
    "port": 4040,
    "base": "/"
  },
  "livereload": true,
  "watch": ["src"],
  "includePaths": ["node_modules"]
}

All config properties are optional except scripts, styles, postcss or markups. You have to specify at least one of them. If you don't have anything to consume, you won't poop. 💩

You can freely remove the properties that you don't need. For example, if you don't want to run a local server, just remove the serve property from the config.

Scripts

Scripts are bundled with esbuild. Supports .js, .ts, .jsx, and .tsx files out of the box — including React and other JSX frameworks. You can specify multiple scripts to bundle. Each script has the following properties:

• in - the input path, can be a file path, an array of file paths, or a glob pattern (e.g. "src/js/*.js"). Globs must use / separators (even on Windows)
• out - the output path, can be a directory or a file path. With multiple inputs it must be a directory — entry points from different directories nest their output under the common ancestor (esbuild's outbase)
• options - the options for the bundler. You can apply most of the esbuild options that are not in conflict with Poops. See esbuild's options for more info.

Options:

• sourcemap - whether to generate sourcemaps or not, sourcemaps are generated only for non-minified files since they are useful for debugging. Default is false. This is a direct esbuild option
• minify - whether to minify the output or not, minification is performed by esbuild and is only applied to non-minified files. Default is false
• justMinified - whether you want to have a minified file as output only. Removes the non-minified file from the output. Useful for production builds. Default is false
• format - the output format, can be iife or esm or cjs - this is a direct esbuild option
• target - the target for the output, can be es2018 or es2019 or es2020 or esnext for instance - this is a direct esbuild option
• jsx - the JSX transform mode, can be transform (default) or automatic. Use automatic for React 17+ JSX runtime which doesn't require importing React in every file - this is a direct esbuild option

scripts property can accept an array of script configurations or just a single script configuration. If you want to bundle multiple scripts, just add them to the scripts array:

{
  "scripts": [
    {
      "in": "src/js/main.ts",
      "out": "dist/js/scripts.js",
      "options": {
        "sourcemap": true,
        "minify": true,
        "justMinified": false,
        "format": "iife",
        "target": "es2019"
      }
    },
    {
      "in": "src/js/other.ts",
      "out": "dist/js/other.js",
      "options": {
        "sourcemap": true,
        "minify": true,
        "justMinified": false,
        "format": "iife",
        "target": "es2019"
      }
    }
  ]
}

JSX/TSX (React) Example

To bundle a React app, just point in to your .jsx or .tsx entry file:

{
  "scripts": [
    {
      "in": "src/js/app.jsx",
      "out": "dist/js/app.js",
      "options": {
        "minify": true,
        "format": "iife",
        "jsx": "automatic"
      }
    }
  ]
}

Setting jsx to automatic uses React's JSX runtime (React 17+), so you don't need import React from 'react' in every file. If you omit jsx or set it to transform, the classic React.createElement transform is used.

As noted earlier, if you don't want to bundle scripts, just remove the scripts property from the config.

Reactor (React Pre-rendering)

The reactor config key defines React components that are pre-rendered to HTML at build time (SSG) and optionally hydrated on the client. This is a separate pipeline from scripts — reactor entries have their own build step, watcher path, and logging tag.

Each reactor entry has the following properties:

• component — the file that default-exports a React component (rendered at build time with renderToString)
• inject — template global variable name for the rendered HTML (available in both Nunjucks and Liquid)
• in (optional) — client entry file for hydration (bundled for the browser)
• out (optional) — output path for the client bundle
• options (optional) — esbuild options for the client bundle (same as script entries: minify, format, target, sourcemap, etc.)

{
  "reactor": [
    {
      "component": "src/js/App.jsx",
      "inject": "app_html",
      "in": "src/js/app-hydrate.jsx",
      "out": "dist/js/app-hydrate.js",
      "options": {
        "minify": true,
        "target": "es2019"
      }
    }
  ]
}

For backwards compatibility, "ssg" is also accepted as a config key — it is treated as an alias for "reactor".

In your templates, use the inject name to insert the rendered HTML:

<div id="root">{{ app_html | safe }}</div>
<script src="js/app-hydrate.min.js"></script>

If you only need server-side rendering without client hydration, omit in and out:

{
  "reactor": [
    {
      "component": "src/js/App.jsx",
      "inject": "app_html"
    }
  ]
}

How it works:

1. Poops bundles the component with react-dom/server for Node.js and calls renderToString
2. The rendered HTML is stored and made available as a template global variable
3. If in/out are specified, the client entry is bundled for the browser
4. At runtime, React hydrates the pre-rendered HTML, making it interactive

Poops does not need react or react-dom as its own dependency — they are resolved from your project's node_modules. In watch mode, changes to files in the reactor component's directory trigger re-rendering and client re-bundling. Markup is recompiled only when the rendered output actually changes. Changes to other JS/TS files only trigger the scripts pipeline — the two are independent.

Note: If you don't need server-side pre-rendering, you can bundle a React app entirely through the regular scripts pipeline — just point in to your .jsx/.tsx entry file and use createRoot on the client. The reactor config is only needed when you want build-time HTML rendering with optional hydration.

Styles

Styles are bundled with Dart Sass. You can specify multiple styles to bundle. Each style has the following properties:

• in - the input path, can be a file path, an array of file paths, or a glob pattern (e.g. "src/scss/*.scss"). Globs must use / separators (even on Windows) and skip Sass partials (_*.scss). Each matched file is compiled separately
• out - the output path, can be a directory or a file path. With multiple inputs it must be a directory — each input compiles to <out>/<basename>.css, so inputs sharing a basename (e.g. a/main.scss and b/main.scss) will overwrite each other
• options - the options for the bundler.

Options:

• sourcemap - whether to generate sourcemaps or not, sourcemaps are generated only for non-minified files since they are useful for debugging. Default is false
• minify - whether to minify the output or not, minification is performed by esbuild. Default is false
• justMinified - whether you want to have a minified file as output only. Removes the non-minified file from the output. Useful for production builds. Defaults to false.
• tokenPaths - a string or array of directory paths containing JSON design token files. Enables the sass-token-importer which lets you @use JSON tokens directly in SCSS. Supports W3C DTCG and Style Dictionary formats with auto-detection.
• tokenOutput - output mode for design tokens: "variables" (default) generates flat SCSS variables, "map" generates nested Sass maps.
• resolveAliases - whether to resolve {path.to.token} alias references in design tokens. Default is true.

styles property can accept an array of style configurations or just a single style configuration. If you want to bundle multiple styles, just add them to the styles array:

{
  "styles": [
    {
      "in": "src/scss/main.scss",
      "out": "dist/css/styles.css",
      "options": {
        "sourcemap": true,
        "minify": true,
        "justMinified": false
      }
    },
    {
      "in": "src/scss/other.scss",
      "out": "dist/css/other.css",
      "options": {
        "sourcemap": true,
        "minify": true,
        "justMinified": false
      }
    }
  ]
}

Design Tokens

You can import JSON design token files directly into your SCSS using the token: prefix. Define your tokens in JSON once and use them as SCSS variables — no manual variable files to keep in sync.

Given a token file src/tokens/colors.json:

{
  "color": {
    "$type": "color",
    "primary": { "$value": "#0066cc" },
    "secondary": { "$value": "#ff6600" },
    "link": { "$value": "{color.primary}" }
  }
}

Add tokenPaths to your styles config:

{
  "styles": [
    {
      "in": "src/scss/index.scss",
      "out": "dist/css/styles.css",
      "options": {
        "tokenPaths": ["src/tokens"]
      }
    }
  ]
}

Then use the token: prefix in your SCSS:

@use "token:colors" as c;

.btn {
  color: c.$color-primary;
}
.btn:hover {
  color: c.$color-secondary;
}
a {
  color: c.$color-link; // resolved from {color.primary} → #0066cc
}

For Sass maps instead of flat variables, set "tokenOutput": "map":

@use "sass:map";
@use "token:colors" as c;

.btn {
  color: map.get(c.$color, primary);
}

As noted earlier, if you don't want to bundle styles, just remove the styles property from the config.

PostCSS (optional)

Process CSS files with PostCSS and any PostCSS plugins. This is a separate pipeline from Styles (Sass) — use it for tools like Tailwind CSS, Autoprefixer, or any other PostCSS plugin.

PostCSS and its plugins are not bundled with Poops. You need to install them in your project:

npm i -D postcss

Each PostCSS entry has the following properties:

• in - the input CSS file path
• out - the output path, can be a directory or a file path
• options - options for the pipeline

Options:

• plugins - an array of PostCSS plugin names to load. Each entry can be a string (plugin name) or a tuple ["plugin-name", { options }] for passing options to the plugin.
• minify - whether to minify the output using esbuild. Default is false
• justMinified - output only the minified file. Default is false

postcss property can accept an array of configurations or a single configuration:

{
  "postcss": {
    "in": "src/css/main.css",
    "out": "dist/css/main.css",
    "options": {
      "plugins": ["@tailwindcss/postcss"],
      "minify": true
    }
  }
}

You can also pass options to plugins using the tuple form:

{
  "postcss": {
    "in": "src/css/main.css",
    "out": "dist/css/main.css",
    "options": {
      "plugins": [["autoprefixer", { "grid": true }]]
    }
  }
}

Build order: PostCSS runs after Styles and Markups in the build pipeline. This means PostCSS plugins can reference the compiled markup output (e.g. Tailwind scanning HTML for utility classes). In watch mode, PostCSS is re-triggered after Styles or Markups recompile.

Tailwind CSS Example

Install the deps, then use a config like this:

npm i -D postcss @tailwindcss/postcss tailwindcss

{
  "postcss": {
    "in": "src/css/main.css",
    "out": "dist/css/main.css",
    "options": {
      "plugins": ["@tailwindcss/postcss"],
      "minify": true
    }
  },
  "markup": {
    "in": "src/markup",
    "out": "dist",
    "site": {
      "title": "Poops + Tailwind",
      "description": "A Tailwind CSS example for Poops"
    },
    "includePaths": ["_layouts", "_partials"]
  },
  "serve": { "port": 4040, "base": "/dist" },
  "livereload": true,
  "watch": ["src"]
}

The CSS entry file (src/css/main.css) simply imports Tailwind:

@import "tailwindcss";

Then use Tailwind utility classes directly in your markup templates. Tailwind v4 auto-detects content sources, so no tailwind.config.js is needed.

Using Sass + Tailwind together: If you want both Sass and Tailwind, keep them as separate pipelines writing to separate output files. The Sass pipeline compiles .scss to CSS, while the PostCSS pipeline handles Tailwind independently. They don't need to chain into each other unless you want PostCSS to post-process the Sass output (e.g. with Autoprefixer) — in that case, point postcss.in to the Sass output file and postcss.out to a different file so the original Sass output is preserved for re-processing.

Markups

• engine (optional) - the template engine to use. Can be "nunjucks" (default) or "liquid". Nunjucks is a Mozilla template engine inspired by Jinja2. Liquid is a Shopify-compatible template engine. Both engines support the same tags, filters, collections, search index, sitemap, and navigation tree features documented below.
• in - the input path, can be a directory or a file path, but please just use it as a directory path for now. All files in this directory will be processed and the structure of the directory will be preserved in the output directory with exception to directories that begin with an underscore _ will be ignored.
• out - the output path, can be only a directory path (for now)
• site (optional) - global data that will be available to all templates in the markup directory. Like site title, description, social media links, etc. You can then use this data in your templates {{ site.title }} for instance.
• data (optional) - is an array of JSON or YAML data files, that once loaded will be available to all templates in the markup directory. If you provide a path to a file for instance links.json with a facebook property, you can then use this data in your templates {{ links.facebook }}. The base name of the file will be used as the variable name, with spaces, dashes and dots replaced with underscores. So the awesome-links.json will be available as {{ the_awesome_links.facebook }} in your templates. The root directory of the data files is in directory. So if you have a data directory in your in directory, you can specify the data files like this data: ["data/links.json"]. The same goes for the YAML files.
• includePaths - an array of paths to directories that will be added to the template engine's include paths. Useful if you want to separate template partials and layouts. For instance, if you have a _includes directory with a header.njk (or header.liquid) partial that you want to include in your markup, you can add it to the include paths and then include the templates like this {% include "header.njk" %}, without specifying the full path to the partial.
• baseURL (optional) - a base URL prefix to use instead of relative path prefixes. When set, {{ relativePathPrefix }} will always resolve to this value (with a trailing slash ensured) instead of being computed relative to each page's depth. Useful when deploying under a subdirectory (e.g. "/blog" for domain.com/blog/). When not set, relative prefixes (./, ../, etc.) are used, which work for any deployment location including subdirectories and file:// URLs.

💡 NOTE: If, for instance, you are building a simple static onepager for your library, and want to pass a version variable from your package.json, Poops automatically reads your package.json if it exists in your working directory and sets the global variable package to the parsed JSON. So you can use it in your markup files, for example like this: {{ package.version }}.

Here is a sample markup configuration using the default Nunjucks engine:

{
  "markup": {
    "in": "src/markup",
    "out": "dist",
    "site": {
      "title": "My Awesome Site",
      "description": "This is my awesome site"
    },
    "data": ["data/links.json", "data/other.yaml"],
    "includePaths": ["_includes"],
    "baseURL": "/blog"
  }
}

To use Liquid instead, set the engine property:

{
  "markup": {
    "engine": "liquid",
    "in": "src/liquid",
    "out": "dist",
    "site": {
      "title": "My Awesome Site",
      "description": "This is my awesome site"
    },
    "data": ["_data/links.json", "_data/other.yaml"],
    "includePaths": ["_layouts", "_partials"]
  }
}

If your project doesn't have markups, you can remove the markup property from the config entirely. No code will be executed for this property.

Nunjucks vs Liquid

Both engines support the same feature set (collections, pagination, search index, sitemap, navigation tree, custom tags, and filters). The main differences are in template syntax:

| Feature | Nunjucks | Liquid | | -------------- | ----------------------------- | ------------------------------------- | | File extension | .njk | .liquid | | Inheritance | {% extends "base.html" %} | {% layout "base.liquid" %} | | Default values | {{ x or "fallback" }} | {{ x \| default: "fallback" }} | | Contains check | {% if "x" in items %} | {% if items contains "x" %} | | Safe output | {{ html \| safe }} | {{ html }} (no escaping by default) | | Includes | {% include "partial.njk" %} | {% render "partial.liquid" %} |

Both engines process .html and .md files in addition to their native extension.

Custom Engines

The engine option also accepts a module specifier — an npm package name or a path relative to your project root. The module's default export must be an engine class:

{
  "markup": {
    "in": "src/markup",
    "out": "dist",
    "engine": "poops-shopify"
  }
}

An engine class implements this contract (see lib/markup/engines/ for the two built-in reference implementations):

export default class MyEngine {
  constructor(templatesDir, includePaths, options) {} // options: { autoescape }
  get fileExtension() {
    return ".liquid";
  } // native template extension
  get indexableExtensions() {
    return new Set([".html"]);
  } // extensions eligible for search index/nav
  get markupExtensions() {
    return "html|liquid|md";
  } // glob alternation of processed extensions
  registerFilters({ timeDateFormat, markupOut }) {}
  registerTags(getOutputDir) {}
  setGlobal(key, value) {}
  removeGlobal(key) {}
  async render(templatePath, context) {
    return "html";
  } // templatePath is an absolute file path
  async renderString(source, context) {
    return "html";
  }
}

Optionally, an engine may implement replaceOutExtensions(outputPath) to control how source extensions map to output extensions (the default maps .md/.njk/.liquid to .html).

The easiest starting point is extending a built-in engine — deep imports are intentionally supported for this:

import LiquidEngine from "poops/lib/markup/engines/liquid.js";

export default class MyEngine extends LiquidEngine {
  registerFilters(opts) {
    super.registerFilters(opts);
    this.engine.registerFilter("shout", (str) => String(str).toUpperCase());
  }
}

Collections & Pagination

Collections turn a directory of pages into a sorted, optionally paginated list — blog posts, changelog entries, documentation. A collection maps to a direct subdirectory of your markup in directory: every .html, .njk, .liquid or .md file inside it (except the index.* file) becomes a collection item.

There are two ways to declare a collection:

1. Front matter auto-discovery — add collection to the front matter of the directory's index file:

---
title: Changelog
collection: true
paginate: 10
sort: date
---

collection: true uses the directory name as the collection name; a string (e.g. collection: changelog) names it explicitly. paginate and sort are optional.

2. Config — list collections in the markup config. The name must match a subdirectory of in:

{
  "markup": {
    "in": "src/markup",
    "out": "dist",
    "collections": [
      "changelog",
      {
        "name": "blog",
        "paginate": 5,
        "sort": { "by": "title", "order": "asc" }
      }
    ]
  }
}

Sorting. By default items are sorted by date, newest first. sort can be a field name shorthand ("sort": "title") or an object { "by": "field", "order": "asc" | "desc" }. Sorting by date compares dates (default order desc); any other field compares alphabetically (default order asc).

Items. Each item exposes its own front matter plus properties Poops adds:

• url - the item's output path relative to the site root (e.g. changelog/my-post.html)
• title - falls back to the file name if not set in front matter
• date - falls back to the file's modification time if not set, with a build warning. Set a real date in front matter — mtime is meaningless on CI checkouts (git clone resets it), so undated posts will reshuffle between deploys.
• wordcount, fileName, filePath, collection

An item with published: false in its front matter is excluded from the collection and its page is not built.

Using collections in templates. Every collection is available as a global variable named after it, on every page:

{% for post in changelog.items %}
  <a href="{{ relativePathPrefix }}{{ post.url }}">{{ post.title }}</a> — {{ post.date | date }}
{% endfor %}

Pagination. With paginate: N set, the collection's index file is rendered once per page of N items: page 1 to out/changelog/index.html, page 2 to out/changelog/2/index.html, and so on. Inside the index template the collection object carries the page state:

| Variable | Description | | --------------------------- | ------------------------------------------------------- | | pageItems | the items on the current page | | pageNumber / totalPages | current page (1-based) / total page count | | pageUrl | URL of the current page (changelog, changelog/2, …) | | nextPage / nextPageUrl | next page number / URL, null on the last page | | prevPage / prevPageUrl | previous page number / URL, null on the first page |

From the example site's changelog/index.html:

{% for post in changelog.pageItems %}
  <div class="post">
    <h2><a href="{{ relativePathPrefix }}{{ post.url }}">{{ post.title }}</a></h2>
    <div class="date">{{ post.date | date }}</div>
    {{ post.description }}
  </div>
{% endfor %}

{% if changelog.totalPages > 1 %}
  {% if changelog.nextPageUrl %}<a href="{{ relativePathPrefix }}{{ changelog.nextPageUrl }}">Next</a>{% endif %}
  {{ changelog.pageNumber }} of {{ changelog.totalPages }}
  {% if changelog.prevPageUrl %}<a href="{{ relativePathPrefix }}{{ changelog.prevPageUrl }}">Previous</a>{% endif %}
{% endif %}

Or use the {% pagination %} shorthand tag (available in both engines), which renders Previous/Next links and a "page of total" counter — with relativePathPrefix applied — and outputs nothing when there is only one page:

{% pagination changelog %}

Item pages themselves are compiled like any other markup file, preserving the directory structure: src/markup/changelog/my-post.md → dist/changelog/my-post.html. A collection directory without an index file still builds its items and exposes the collection to templates — only the paginated listing pages are skipped.

Custom Tags

image

Poops can generate responsive <img> elements with srcset attributes. Image processing (resize, format conversion) is handled externally — Poops discovers the generated variants on disk and produces the correct HTML markup.

Naming convention: Your image tool should output variants as {name}-{width}w.{ext}. For example, given photo.jpg, the expected variants are: photo-320w.jpg, photo-640w.jpg, photo-320w.webp, photo-640w.webp, etc.

{% image %} tag — generates a full <img> element:

Nunjucks:

{% image 'static/photo.jpg', alt='Hero', class='hero-img', sizes='(max-width: 640px) 100vw, 50vw' %}

Liquid:

{% image 'static/photo.jpg', alt: 'Hero', class: 'hero-img', sizes: '(max-width: 640px) 100vw, 50vw' %}

Output:

<img
  src="static/photo-640w.jpg"
  srcset="
    static/photo-320w.webp 320w,
    static/photo-640w.webp 640w,
    static/photo-960w.webp 960w
  "
  sizes="(max-width: 640px) 100vw, 50vw"
  alt="Hero"
  class="hero-img"
  loading="lazy"
/>

• Scans the output directory for files matching {name}-{width}w.{ext}
• Groups by format, prefers avif > webp > original format for srcset
• Uses the middle-sized variant as src fallback
• Prepends relativePathPrefix automatically
• Defaults: sizes="100vw", loading="lazy"
• Falls back to a plain <img src="..."> if no variants are found

Named crops with size — pass a size kwarg to build the <img> from a named crop/resize group instead of the default responsive widths. The whole group becomes its own srcset (each crop has its own aspect ratio), so a square thumbnail set, a wide banner set, etc. each get correct srcset/width/height:

{% image 'static/photo.jpg', size='thumb', alt='', sizes='240px' %}

<img src="static/photo-thumb-480w.webp"
     srcset="static/photo-thumb-480w.webp 480w, static/photo-thumb.webp 960w"
     width="480" height="480" sizes="240px" alt="" loading="lazy">

This requires the poops-images compile cache (named-size widths are read from it). The size name matches a named entry in your images.sizes config. The largest member of the group is written without a width suffix (photo-thumb.webp) — poops still srcsets it at its real width from the cache.

poops-images integration: if a .poops-images-cache.json compile cache is found in the output directory (poops-images writes one next to the images it generates), Poops reads variants from it instead of scanning the directory. On top of the scan behavior above, the cache gives you:

• width and height attributes on the <img> element (exact dimensions from the cache — prevents layout shift). Pass your own width/height kwargs to override.
• Correct src when the source format was converted (e.g. photo.heic → photo.jpg), even when there are no size variants.
• By default the srcset is built only from the plain {name}-{width}w.{ext} width variants. Named sizes (photo-thumb-480w.webp) and preprocessed outputs (photo-blurred-640w.jpg) are kept out of it — they are crops and effects with their own aspect ratios. Reach a named crop group on purpose with the size kwarg above (or the srcset filter's second argument).
• EXIF metadata via the exif filter (see below).

googleFonts

Generates Google Fonts <link> tags with preconnect hints. Accepts an array of font names (strings) or font objects with weight/italic options.

Nunjucks (supports inline arrays):

{% googleFonts ["Open Sans", "Roboto"] %}

Liquid (pass a variable — inline arrays are not supported in Liquid syntax):

{% googleFonts fonts %}

Where fonts is defined in a data file (e.g. fonts.json):

["Open Sans", "Roboto"]

Output:

<link rel="preconnect" href="https://fonts.googleapis.com" />
<link rel="preconnect" href="https://fonts.gstatic.com" crossorigin />
<link
  href="https://fonts.googleapis.com/css2?family=Open+Sans&family=Roboto&display=swap"
  rel="stylesheet"
/>

With specific weights and italics (Nunjucks):

{% googleFonts ["DM Sans", {name: "Poppins", weights: [400, 700], ital: true}] %}

With specific weights and italics (Liquid — via data file):

["DM Sans", { "name": "Poppins", "weights": [400, 700], "ital": true }]

Font object options:

• name — font family name
• weights — array of weight values (e.g. [400, 700])
• ital — set to true to include italic variants
• display — font-display strategy, defaults to swap (Nunjucks only, as a keyword argument)

highlight

Syntax-highlights code blocks at build time using highlight.js, eliminating layout shift caused by client-side highlighting. Code is pre-highlighted in the HTML output — you only need the highlight.js CSS theme on the client, not the JS.

{% highlight %} tag — wraps a code block with syntax highlighting (same syntax in both engines):

{% highlight 'javascript' %}
const greet = (name) => {
  return `Hello, ${name}!`;
};
{% endhighlight %}

Output:

<pre><code class="hljs language-javascript"><span class="hljs-keyword">const</span> greet = <span class="hljs-function">...</span></code></pre>

The language argument is optional. If omitted, highlight.js will attempt to auto-detect the language.

Markdown code fences are also highlighted automatically at build time:

```json
{ "name": "poops" }
```

Registered languages: javascript/js, typescript/ts, css, scss, html, xml, json, bash/sh, shell, python/py, ruby/rb, php, java, c, cpp, csharp/cs, go, rust/rs, yaml/yml, markdown/md, sql, diff.

Custom Filters

All filters are available in both engines. The only syntax difference is how arguments are passed: Nunjucks uses parentheses | filter("arg"), Liquid uses a colon | filter: "arg".

• slugify — slugifies a string. Usage: {{ "My Awesome Title" | slugify }} will output my-awesome-title

• jsonify — serializes a value to JSON. Usage: {{ myObject | jsonify }}

• markdown — renders a markdown string to HTML with GitHub Flavored Markdown extras: emoji shortcodes (e.g. :rocket: → 🚀), alert callouts (> [!NOTE], [!TIP], [!IMPORTANT], [!WARNING], [!CAUTION], [!INFO]) and footnotes ([^1]). Code fences are syntax-highlighted and headings get slug ids plus permalink anchors. Usage: {{ "**bold** :rocket:" | markdown }}

• date — formats a date string. Uses dayjs format tokens. A default format can be set via the timeDateFormat config option.

  • Nunjucks: {{ "2024-01-15" | date("MMMM D, YYYY") }}
  • Liquid: {{ "2024-01-15" | date: "MMMM D, YYYY" }}

• concat — returns a new array with the value appended (does not mutate the original):

  • Nunjucks: {{ items | concat("c") }}
  • Liquid: {{ items | concat: "c" }}

• push — appends a value to an array in place (mutates the original):

  • Nunjucks: {{ items | push("c") }}
  • Liquid: {{ items | push: "c" }}

• svg — reads an SVG file and injects it inline. The path is resolved relative to the project root. Returns empty string if the file doesn't exist or isn't an SVG. Usage: {{ 'src/icons/logo.svg' | svg }}

• highlight — syntax-highlights a code string at build time using highlight.js. Takes an optional language argument. If the language is omitted, highlight.js will auto-detect it. Returns a <pre><code class="hljs"> block with highlighted markup.

  • Nunjucks: {{ someCodeVariable | highlight('javascript') }}
  • Liquid: {{ someCodeVariable | highlight: 'javascript' }}

• groupby — groups an array of objects by a field value. Returns an array of { key, items } objects. Supports an optional second argument for date part extraction (year, month, day). Groups preserve insertion order, so if items are sorted by date descending, groups will be too.

  • Nunjucks: {{ changelog.items | groupby("author") }} or {{ changelog.items | groupby("date", "year") }}
  • Liquid: {{ changelog.items | groupby: "author" }} or {{ changelog.items | groupby: "date", "year" }}

  Example — group posts by year:

  {% set byYear = changelog.items | groupby("date", "year") %}
  {% for group in byYear %}
    <h2>{{ group.key }}</h2>
    {% for post in group.items %}
      <p>{{ post.title }}</p>
    {% endfor %}
  {% endfor %}

• srcset — returns just the srcset attribute value:

<img
  src="static/photo-640w.jpg"
  srcset="{{ 'static/photo.jpg' | srcset }}"
  sizes="100vw"
  alt="Hero"
/>

Returns: static/photo-320w.webp 320w, static/photo-640w.webp 640w, static/photo-960w.webp 960w

Pass a named crop/resize group as the second argument to get that group's srcset instead of the default widths: {{ 'static/photo.jpg' | srcset: 'thumb' }} → static/photo-thumb-480w.webp 480w, static/photo-thumb.webp 960w.

• exif — returns the EXIF metadata object for an image from the poops-images compile cache (.poops-images-cache.json in the output directory), or null if there is no cache or no EXIF data. The object includes camera (make, model, lensModel), exposure (fNumber, exposure.formatted, iso, focalLength35mm), dateTime, and gps (latitude.formatted, longitude.formatted, altitude, and a ready-made googleMapsUrl).

  Example — a photo with date and location caption:

  {% set meta = 'static/photo.jpeg' | exif %}
  <figure>
    {% image 'static/photo.jpeg', alt='Sendai at dusk' %}
    {% if meta %}
      <figcaption>
        {{ meta.dateTime | date("MMMM D, YYYY") }}
        {% if meta.gps %}
          — <a href="{{ meta.gps.googleMapsUrl }}">{{ meta.gps.latitude.formatted }}, {{ meta.gps.longitude.formatted }}</a>
        {% endif %}
        {% if meta.model %}· {{ meta.model }}{% endif %}
      </figcaption>
    {% endif %}
  </figure>

• images — lists all images under a site-relative directory from the poops-images compile cache. Returns an array of { path, width, height, date, exif, outputs } objects, or an empty array if there is no cache:

  • path — site-relative source path, feeds straight into the {% image %} tag
  • date — exif.dateTime when the photo has EXIF, file modification time otherwise — so sorting and grouping work for every image
  • outputs — every generated file for the image (site-relative), useful for picking LQIP or preprocessed variants
  • Pass a subdirectory ('static/images/2025') to scope the list

  The path is relative to your markup out dir, not to images.in. It mirrors where the generated images land — i.e. images.out made relative to markup out. So if images.out is _site/static/images and markup out is _site, the images live at static/images on the site and you call 'static/images' | images (not 'images', which would look in _site/images and return []). This is the same path you already pass to the {% image %} tag.

  Combined with groupby, engine-native sorting and the {% image %} tag, a photo gallery is a pure template concern. This is the Instagram-style square grid — size='thumb' pulls the named crop group and its auto-generated srcset (define a thumb crop in images.sizes):

  Nunjucks:

  {% for group in 'static/images' | images | sort(reverse=true, attribute='date') | groupby("date", "year") %}
    <h2>{{ group.key }}</h2>
    <div class="grid">
      {% for img in group.items %}
        <figure>
          {% image img.path, size='thumb', alt='', sizes='(max-width: 640px) 50vw, 240px' %}
          {% if img.exif and img.exif.gps %}
            <figcaption>
              <a href="{{ img.exif.gps.googleMapsUrl }}">📍</a> {{ img.date | date("MMM D, YYYY") }}
            </figcaption>
          {% endif %}
        </figure>
      {% endfor %}
    </div>
  {% endfor %}

  Liquid:

  {% assign imgs = 'static/images' | images | sort: 'date' | reverse %}
  {% assign groups = imgs | groupby: "date", "year" %}
  {% for group in groups %}
    <h2>{{ group.key }}</h2>
    <div class="grid">
      {% for img in group.items %}
        <figure>{% image img.path, size: 'thumb', alt: '' %}</figure>
      {% endfor %}
    </div>
  {% endfor %}

Search Index, Sitemap & Navigation

Poops can automatically generate a JSON search index, an XML sitemap and a navigation tree from your compiled pages. All are generated in a single pass during the markup compilation phase.

To enable, add searchIndex, sitemap and/or nav to your markup config:

{
  "markup": {
    "in": "src/markup",
    "out": "dist",
    "options": {
      "searchIndex": "search-index.json",
      "sitemap": "sitemap.xml"
    }
  }
}

The string shorthand sets the output filename with default options. For more control, use the object form:

{
  "searchIndex": {
    "output": "search-index.json",
    "minWordLength": 3,
    "maxKeywords": 20,
    "globalFrequencyCeiling": 0.8,
    "stopWords": "path/to/custom-stop-words.json"
  },
  "sitemap": {
    "output": "sitemap.xml"
  }
}

Search Index options:

• output — output filename, written to the markup output directory
• minWordLength — minimum word length to consider as a keyword (default: 3)
• maxKeywords — maximum keywords per page (default: 20)
• globalFrequencyCeiling — drop words appearing in more than this fraction of all pages (default: 0.8, meaning words found in 80%+ of pages are dropped as non-discriminating)
• stopWords — customise stop word filtering:
  • omit or undefined — uses the bundled English stop words
  • false — disables stop word filtering entirely
  • ["word1", "word2"] — inline array of stop words
  • "path/to/file.json" — path to a JSON array file (relative to project root)

Search Index output format:

All front matter fields are passed through to the index automatically. Internal fields (content, isIndex, layout, published) are stripped. If a page defines keywords in its front matter, those are used as-is instead of auto-extracted ones.

[
  {
    "title": "My Post",
    "date": "2024-01-15",
    "description": "A great post about things.",
    "collection": "blog",
    "tags": ["javascript", "bundler"],
    "url": "blog/my-post.html",
    "keywords": ["javascript", "bundler", "webpack", "esbuild"]
  }
]

Sitemap generates a standard sitemap.xml with <loc> and <lastmod> (from front matter date). If site.url is set in your markup config, it is prepended to all URLs. Collection index/pagination pages are included in the sitemap but excluded from the search index.

Pages with published: false in their front matter are excluded from both outputs.

Navigation tree builds your page hierarchy as sidebar-ready data, exposed two ways: as the nav template global (loaded automatically, always reflecting the current build) and as a nested JSON file for client-side rendering. Subpages nest automatically from URL structure: guide/index.md becomes a parent node and guide/getting-started.md, guide/advanced/config.md become its (and its subsections') children. Add nav to your markup config:

{
  "markup": {
    "in": "src/markup",
    "out": "dist",
    "options": {
      "nav": "nav.json"
    }
  }
}

The string shorthand sets the output filename. For docs sites, use the object form:

{
  "nav": {
    "output": "nav.json",
    "root": "docs",
    "collections": "index",
    "home": false
  }
}

Navigation options:

• output — output filename, written to the markup output directory
• collections — how to treat collection pages (default true):
  • true — include every collection page, nested under its collection
  • false — exclude all collection pages (drops a blog's posts from the sidebar)
  • ["docs", ...] — allowlist; only these collections' pages are included (non-collection pages are always kept)
  • "index" — include only each collection's landing page as a single leaf, not its posts
• home — false drops the site's root index page (url "") from the tree (default true)
• root — scope the tree to a subdirectory (e.g. "docs"); its children are emitted at the top level and the section's own index page is pinned first as the overview link. URLs are kept full (docs/getting-started), so the homepage is naturally excluded

Front matter fields that shape the tree:

• order — a number that sorts a page within its sibling level (optional). Pages without order fall to the bottom, sorted alphabetically by title — so a hand-authored docs sequence (1, 2, 3) wins over alphabetical. This applies to the homepage too: give it order: 0 in its front matter to pin it to the top, otherwise it sorts last like any page without order.
• nav: false — hide a page from the sidebar (it stays in the search index and sitemap).
• navTitle — a sidebar label that overrides title.

Navigation output format — each node has a title, a url (omitted on synthesized section nodes that have no index page of their own), an order when set, and children when it has subpages:

[
  {
    "title": "Guide",
    "url": "guide",
    "order": 1,
    "children": [
      {
        "title": "Getting Started",
        "url": "guide/getting-started",
        "order": 1
      },
      {
        "title": "Advanced",
        "url": "guide/advanced",
        "children": [{ "title": "Config", "url": "guide/advanced/config" }]
      }
    ]
  }
]

Pages with published: false or nav: false are excluded. If nothing survives filtering, an empty array [] is written so consumers never have to special-case a missing file.

Rendering the sidebar. The tree is arbitrarily deep, so render it with a recursive template. The nav global is built from front matter in a pre-pass before templating, so it always reflects the current build — no need to load the generated nav.json back in via data (which would be one build behind). The written nav.json is for client-side rendering (fetch('/nav.json')). Prefix each url with relativePathPrefix so links resolve from any page depth.

Nunjucks — a self-recursing macro:

{% macro navtree(items) %}
<ul>
  {% for item in items %}
  <li>
    {% if item.url != null %}<a href="{{ relativePathPrefix }}{{ item.url }}">{{ item.title }}</a>
    {% else %}<span>{{ item.title }}</span>{% endif %}
    {% if item.children %}{{ navtree(item.children) }}{% endif %}
  </li>
  {% endfor %}
</ul>
{% endmacro %}

{{ navtree(nav) }}

Note the != null check: the homepage node's url is an empty string (a valid link — relativePathPrefix resolves it), while synthesized section nodes have no url at all. A plain {% if item.url %} would wrongly demote the homepage to a <span>. Node titles already have navTitle applied, so {{ item.title }} is all you need.

Liquid — a partial that recurses via render (save as _partials/navtree.liquid). Liquid treats empty strings as truthy, so the plain if is safe here:

<ul>
  {% for item in items %}
  <li>
    {% if item.url %}<a href="{{ relativePathPrefix }}{{ item.url }}">{{ item.title }}</a>
    {% else %}<span>{{ item.title }}</span>{% endif %}
    {% if item.children %}{% render 'navtree', items: item.children, relativePathPrefix: relativePathPrefix %}{% endif %}
  </li>
  {% endfor %}
</ul>

{% render 'navtree', items: nav, relativePathPrefix: relativePathPrefix %}

Images (optional)

Process and optimize images — compression, responsive size variants, format conversion (WebP/AVIF), crops and EXIF extraction — by running poops-images as part of the build. This is what feeds the {% image %} tag, the exif/images filters and the .poops-images-cache.json compile cache described in Custom Tags and Custom Filters.

poops-images (and its sharp dependency) is not bundled with Poops. Install it in your project only if you use the images config:

npm i poops-images

If the images key is present but poops-images is not installed, Poops logs a warning and skips image processing — the rest of the build still runs.

The images value is a poops-images config object (see the poops-images options reference). The most common keys:

• in — source images directory
• out — output directory (keep it distinct from in, and outside your watched source, so generated variants don't retrigger the build)
• sizes — responsive widths to generate
• format — target formats (e.g. ["webp"], or "smart" to keep whichever of JPEG/WebP is smaller)
• verbose - defaults to false, so you get a single [image] summary line (count + time) instead of one log per file. Set "verbose": true to restore the per-file logs.

{
  "images": {
    "in": "src/images",
    "out": "dist/images",
    "sizes": [{ "width": 640 }, { "width": 1280 }],
    "format": "smart"
  }
}

Images are processed before markup, so {% image %} and the images filter always read a fresh cache. In watch mode, changing a source image reprocesses it and recompiles markup; deleting one removes its generated variants and updates the galleries that referenced it. Custom handlers and composite overlays resolve relative to your poops.json.

Copy

Configuration entry to copy files or directories - copy your static files like images and fonts, for instance, from src to dist directory. This feature was added to enable moving static files if you deploy GitHub pages via a GitHub action. If you don't want to use this feature, simply exclude the copy property from your config file.

Here is a sample copy configuration which will copy the static directory and it's contents to the dist directory:

{
  "copy": {
    "in": "src/static",
    "out": "dist"
  }
}

You can specify a list of input paths and pass them to an output directory, for instance:

{
  "copy": {
    "in": ["src/static/ogimage.jpg", "src/static/favicon.ico", "src/fonts"],
    "out": "dist"
  }
}

💡 NOTE: Copy property can also accept the list of objects containing in and out properties. For instance:

{
  "copy": [
    {
      "in": ["src/static/ogimage.jpg", "src/static/favicon.ico", "src/fonts"],
      "out": "dist"
    },
    {
      "in": "images",
      "out": "dist/static"
    }
  ]
}

💡 NOTE: Copy can also accept GLOB and EXTGLOB patterns as input paths, except POSIX character classes (e.g. [[:alpha:]]):

{
  "copy": {
    "in": [
      "images/**/awesome.{jpeg,jpg,png}",
      "notes/info[0-9].txt",
      "notes/doc?.txt",
      "notes/memo*.txt",
      "notes/log[!123a].txt",
      "assets/!(vendor)/*.js",
      "fonts/@(woff|woff2)/*.+(woff|woff2)",
      "docs/?(intro|overview).md"
    ],
    "out": "dist"
  }
}

Banner (optional)

Here you can specify a banner that will be added to the top of the output files. It is templatable via mustache. The following variables are available from your project's package.json:

• name
• version
• homepage
• license
• author
• description

Here is a sample banner template.

/* {{ name }} v{{ version }} | {{ homepage }} | {{ license }} License */

You can always pass just a string, you don't have to template it.

If you don't want to add a banner, just remove the banner property from the config.

Local Server (optional)

Sets up a local server for your project.

Server options:

• port - the port on which the server will run
• base - the base path of the server, where your HTML files are located

If you don't want to run a local server, just remove the serve property from the config.

Live Reload (optional)

Sets up a livereload server for your project.

Live reload options:

• port - the port on which the livereload server will run
• exclude - an array of files and directories to exclude from livereload
• extraExts - an array of extra file extensions (without the dot) that trigger a browser refresh, added to the defaults
• exts - an array of file extensions that replaces the default list entirely

By default a refresh is triggered by changes to: html, css, js, png, gif, jpg, php, php5, py, rb, erb, coffee. If you work with other file types, for example Slim or Nunjucks templates, add them:

{
  "livereload": {
    "extraExts": ["slim", "njk"]
  }
}

livereload can only be true, which means that it will run on the default port (35729) or you can specify a port:

{
  "livereload": {
    "port": whateverPortYouWant
  }
}

You can also exclude files and directories from livereload:

{
  "livereload": {
    "exclude": ["some_directory/**/*", "some_other_directory/**/*"]
  }
}

In order for Livereload to work, you need to add the following script snippet to your HTML files in your development environment:

<script>
  document.write(
    '<script src="http://' +
      (location.host || "localhost").split(":")[0] +
      ':35729/livereload.js?snipver=1"></' +
      "script>",
  );
</script>

Be mindful of the port, if you have specified a custom port, you need to change the port in the snippet as well.

You can also use a browser extension for livereload, for instance here is one for Chrome. You can find also extensions for Firefox and Opera, but NOT for Safari.

If you don't want to run livereload, just remove the livereload property from the config, or set it to false.

Watch (optional)

Sets up a watcher for your project which will rebuild your files on change.

watch property accepts an array of paths to watch for changes. If you want to watch for changes in the src directory, just add it to the watch array:

{
  "watch": ["src"]
}

If you don't want to watch for file changes, just remove the watch property from the config.

Include Paths (optional)

This property is used to specify paths that you want to resolve your imports from. Like node_modules. You don't need to specify the includePaths, node_modules are included by default. But if you do specify includePaths, you need to include node_modules as well, since this change will override the default behavior.

Same as watch property, includePaths accepts an array of paths to include. If you want to include lib directory for instance, just add it to the includePaths array:

{
  "includePaths": ["node_modules", "lib"]
}

Why?

Why doesn't anyone maintain GULP anymore? Why does Parcel hate config files? Why are Rollup and Webpack so complex to setup for simple tasks? Vite???? What's going on?

I'm tired... Tired of bullshit... I just want to bundle my scss/sass and/or my js/ts to css and iife/esm js, by providing input and output paths for both/one. And to be able to have minimal easily maintainable dependencies. I don't need plugins, I'll add the features manually for the practice I use. That's it. The f**king end.

To better illustrate it, here is a sample diff of Poops replacing Rollup:

This is a bundler written by me for myself and those like me. Hopefully it's helpful to you too.

Love :heart: and peace :v:.