Run WebAssembly Containers on Raspberry Pi Using Atym

Atym is a container orchestration platform that makes it easy to develop, deploy, secure, and manage applications on resource-constrained edge devices at scale. Built on WebAssembly (Wasm), Atym extends cloud-native principles to devices ranging from tiny microcontrollers with as little as 256KB of memory to full Linux systems like the Raspberry Pi.

Whether you're targeting MCU-based hardware running Zephyr RTOS or CPU-based devices running Linux, Atym provides a unified workflow: build your application once, push it to the Atym Hub, and deploy it to any supported device. The Atym Runtime handles execution, isolation, and hardware access, while the Atym Hub gives you a web console and CLI for remote management of individual devices or entire fleets.

The runtime is built on Ocre, an open-source project hosted by the Linux Foundation, ensuring you're working with transparent, community-driven technology rather than a proprietary black box.

In this guide, you will prepare a Raspberry Pi in headless mode, install and configure the Atym runtime service, set up a development environment for building Wasm containers, and deploy example code.

This guide assumes you are comfortable using the terminal and have basic familiarity with Raspberry Pi and Linux.Documentation references:

• Atym Documentation
• Linux Runtime Setup
• Atym CLI Setup
• Your First Atym Container
• Ocre GPIO API
• Raspberry Pi Imager

1. Requirements

Hardware

• Raspberry Pi 4 or 5 (64-bit OS required)
• microSD card (32 GB+ recommended)
• Network connection (Ethernet or Wi-Fi)

Software

• Atym CLI (installed on development machine)
• VS Code + Dev Containers
• Docker
• Raspberry Pi Imager

2. Development Environment Setup

Atym provides a preconfigured development container that includes the full toolchain needed to build WebAssembly containers. Using the Dev Container is the recommended approach because it avoids manual installation of the WASI SDK and build tools on your host system.

Before continuing, make sure you have:

• Docker installed and running
• Visual Studio Code
• The VS Code Dev Containers extension

On your development machine, clone the Atym getting-started repository:

If you already cloned without submodules:

Open the directory in VS Code:

Run the Dev Containers: Open Folder in Container... command from the Command Palette (Cmd + Shift + P on Mac, or Ctrl + Shift + P on Windows).

Select the folder containing the cloned repository.

The VS Code window will reload and create the container. This may take a few minutes the first time.

You can also run the toolchain container interactively:

What the Dev Container Provides

Once the container is running, your environment includes:

• wasi-sdk for compiling Wasm binaries
• CMake, Make, and Ninja build tools
• WABT and iwasm for Wasm tooling
• The Atym CLI preinstalled and configured

You can confirm everything is set up correctly by opening a terminal in VS Code running:

You should see output similar to:

Then associate the CLI with your Atym account:

From this point on, all build commands in the guide should be run inside the Dev Container unless explicitly stated otherwise.

3. Register the Raspberry Pi as a Device

Run on your development machine:

If successful, you'll receive credentials:

Save these values — you will need all of them to configure the runtime:

• deviceUUID — unique identifier for this device
• pskSecret — pre-shared key for secure communication
• tenantUUID — your organization's tenant identifier

You can also retrieve your tenant ID with:

4. Setting Up the Raspberry Pi (Headless Mode)

Install Raspberry Pi Imager

Download from: https://www.raspberrypi.com/software/

Flash a 64-bit OS

1. Open Raspberry Pi Imager.

2. Choose OS → Raspberry Pi OS (64-bit) or Ubuntu Server (64-bit).

3. Select your SD card.

Configure headless mode

1. Open advanced settings (Ctrl+Shift+X or the gear icon).

2. Enable:

• SSH
• Hostname
• Wi-Fi (if required)

3. Set username/password, locale, and timezone.

4. Write the image.

Insert the SD card into the Pi and power it on.

5. Install the Atym Runtime on the Pi

SSH into your Pi:

If mDNS is unavailable, find the IP via router or:

Download and extract the Atym runtime for Raspberry Pi (aarch64):

6. Configure the Runtime

Start and enable:

When your device successfully connects, you'll see:

7. Deploy the “Hello World” Container

The getting-started repository includes a hello-world sample written in C. In your Dev Container terminal, navigate to it:

8. Build the Application

This creates hello-world.wasm, the WebAssembly module that will be packaged into an Atym container.

Build the Atym Container

Return to the sample root and build the container:

The atym build command reads the build.yaml file in the project directory to package your Wasm binary into an Atym container. You should see a new .atym directory created in your home directory containing the container.

9. Deploy

The first command pushes your container to the Atym Hub (which works like a Docker registry. Atym containers are OCI-compliant). The second deploys it to your device.

10. Verify Successful Deployment!

You should see a success message in your console similar to:

After running atym run, the Atym Hub will deploy your container to the device. You can verify the container is running:

This should show your hello-world container in the list.

You can verify the container is running on your device:

This should show your hello-world container in the list with a running status.

You've successfully set up a Raspberry Pi with the Atym runtime and deployed your first Wasm container. From here you can:

• Sign up for the Eval Program!
• Explore more samples in the samples/ directory (GPIO, sensors, timers, messaging)
• Check out the Build and Deploy Guide for creating custom applications
• Learn about the Atym SDK APIs for hardware interaction
• Visit the Atym Hackster page for more project ideas
• Join the Atym Discord to connect with other developers

Troubleshooting & Reference

Runtime connection issues

• Server: coapgw.prod.atym.io
• Port: 5684
• Device ID format: deviceUUID@TENANT_ID
• PSK must match the issued secret

Build problems

• Ensure Dev Container is active
• Validate toolchain path
• Check YAML formatting

Useful Commands

Devices

Containers

Need help? Contact eval@atym.io for evaluation program support.