Popcorn runs Elixir and Erlang applications in the browser on a BEAM virtual machine compiled to WebAssembly.

Please report issues and discuss large contributions before you start work.

Release channels

The stable 0.3 release uses AtomVM.

The 0.4 prerelease uses the BEAM virtual machine from Erlang/OTP, compiled to WebAssembly. It runs compiled BEAM code in a Web Worker and supports standard OTP processes, message passing, and supervision.

Use the Popcorn 0.4 setup guide for the prerelease. The stable npm channel remains on Popcorn 0.3 until the 0.4 release.

Documentation

The stable documentation is available at https://hexdocs.pm/popcorn.

The versioned 0.4 prerelease documentation is available at https://popcorn.hexdocs.pm/0.4.0-next.0/.

Examples

The examples are hosted at popcorn.swmansion.com, and the source code is in the examples/ directory.

See also third-party examples:

• Running Popcorn on iOS (WebView based): https://github.com/u9g/uno-royale
• A collection of local Live View demos: https://petermm.github.io/popcorn_live_view/

Repository Structure

• popcorn-2/ - Popcorn 0.3 implementation based on AtomVM.
• popcorn/ - Popcorn 0.4 implementation based on Erlang/OTP.
• examples/ - Example projects showcasing Popcorn features, hosted at popcorn.swmansion.com. Examples use development version of Popcorn.
• landing-page/ - Popcorn landing page.
• language-tour/ - Interactive Elixir language tour running purely in the browser.
• local-live-view/ - Experimental client-side LiveView implementation.
• scripts/ - Shell scripts for development, testing, and CI tasks.
• docker/ - Dockerfiles and nginx configs for CI and deployment.

Development

We use mise to manage tool versions and run tasks. Install it, then:

mise install
mise run dev

This installs all dependencies (Elixir, Node, pnpm) and starts the JS library in watch mode.

To develop with an example or project:

mise run dev --example hello-popcorn
mise run dev --project landing-page
mise run dev --project language-tour

Run scripts/dev.sh --help to see all available examples and projects.

Testing

mise run test            # Elixir unix tests (default)
mise run test --wasm     # Elixir wasm tests
mise run test --js       # JS tests

The required runtime build depends on the package that you change. See the package documentation for its toolchain and native build requirements.

Other tasks

mise run clean           # Clean build artifacts
mise run clean --all     # Clean everything including examples

All tasks are thin wrappers around scripts/*.sh — you can run those directly.

Authors

Popcorn is created by Software Mansion.

Since 2012 Software Mansion is a software agency with experience in building web and mobile apps as well as complex multimedia solutions. We are Core React Native Contributors and experts in live streaming and broadcasting technologies. We can help you build your next dream product – Hire us.

Copyright 2025, Software Mansion

Licensed under the Apache License, Version 2.0