Never Print Magazines


    0.2.0 • Public • Published


    Travis (.org) npm David Gitter

    Packem is an extensively precompiled general-purpose JavaScript module bundler with a focus on performance, flexibility and extendibility. Its crust is built with Rust, a zero-cost abstraction systems programming language with guaranteed memory safety.

    Note: This is a pre-release version. Do not use it in production.

    Build Status

    Since the v0.2 release, prebuilt Packem binaries are available for UNIX systems only. Binaries for Windows are not available for versions below v1.4.

    Windows macOS Linux (Ubuntu)

    Additionally, Node 12 shipped a more stable implementation of the N-API which does not synchronize with the bindings implemented for the LC. For that reason, only the current versions of Node are battle-tested:

    Node 10 Node 9 Node 8

    Table of Contents

    1. Why Packem?
    2. Installation
    3. Plugins
    4. Further Reading
    5. Contributing
    6. FAQ
    7. License

    Why Packem?

    • Hypersonic speeds that go +2X faster than ParcelJS.
    • Light and efficient outputs.
    • Unique configuration style that will not make you cry.
    • Code Splitting with dynamic imports.
    • Comprehensive & versatile plugin API with an elegant approach.
    • Common plugins for smoother development experience.

    Packem (v0.1.3-alpha) is +2X faster than Parcel (v1.12.3 - with multicore compilation).

    Modern bundlers today do optimize your code heavily, minify them and create near-perfect bundles but it comes at an expensive cost, time. The time slice is worth the effort to boost your productivity and not unnecessarily spending too much time on the tool.

    Packem's real power lies in its usage of Rust, which is the state-of-the-art in high performance solutions. This delivers close-to-the-metal speed when compared against other bundlers without comprimising features.

    In a comparison of Packem against Parcel, each bundler had to compile the entire Lodash v4.17.1 to a single bundle and this was the results of the speed test:

    Test No. Packem Parcel
    1 4.23s 11.01s
    2 (cold) 5.12s 12.39s
    3 4.55s 11.80s


    Packem v0.2 uses a faster method of parsing the module graph using V8's JSON.parse() on larger graphs, making it upto 1.2-2.0x faster than previous versions.


    Packem is distrubuted as an npm package, so you can install it globally by executing the following command:

    # Default installation method (with npm) 
    npm install -g packem
    # For Yarn, run 
    yarn global add packem

    Checkout the Getting Started guide for more details.


    Packem uses a comprehensive class-based event system. Based off of this, plugins are instantiated in order of definition in the configuration during build time. Built-in events are also rehydrated into the plugins which they can hook onto using the PackemEventDispatcher API. More details on this can be found in the Plugins API.

    Most of the common plugins are not included with a single installation of Packem and will require you to install them manually. Some of these common plugins include:

    • dev-plugin - An abstraction of Packem's development toolkit i.e. the development server, watcher and other development utilities. This means, in essence, Packem doesn't enforce development tools by default.
    • file-plugin - Loads common structural and text-based file formats to their appropriate equivalents in JavaScript like plain text files to strings & YAML files to their respective JSON object representations.
    • minify-plugin - Uses terserjs to crunch and optimize your JavaScript into tiny obfuscated files and write it to the output path.
    • style-plugin - Responsible for bundling SASS/SCSS, LESS & PostCSS to plain CSS which is then injected into the webpage at runtime.
    • image-plugin - Processes a PNG, JPG/JPEG, GIF, WebP or SVG file, compresses it with a few options like quality, compressionRatio and dithering to create efficiently optimized images that still retain fidelity.
    • bundle-stats-plugin - Checks if your bundles exceed a certain customizable constraint/limit and issues tabular diagnostics with details like bundle size vs the pre-defined limit.
    • markdown-plugin - Transforms a Markdown file into escaped HTML and then returns the result into the bundling pipeline.
    • coffeescript-plugin - Compiles CoffeeScript to JavaScript then appends it to the mainstream bundle.

    Further Reading


    Packem is a community-led project. We depend on your contributions to sustain this project through financial support, filing issues and presenting PRs. Check the contribution guidelines for more details.


    Check the FAQ page to get help on some common caveats.


    This project is licensed under the MIT License.




    npm i packem

    DownloadsWeekly Downloads






    Unpacked Size

    7.17 MB

    Total Files


    Last publish


    • bukharim96