Demo WASM in Serverside with NodeJS

In this tutorial, you’ll learn how to compile a simple C program into WebAssembly (WASM) using Emscripten and then execute it in a Node.js environment. The workflow mirrors browser-based builds, but outputs a JavaScript “glue” file suitable for server-side execution.

Prerequisites

Node.js (tested with v14.18.2)
Emscripten SDK with emcc available in your PATH

Before you begin, make sure you’ve installed Node.js and set up the Emscripten SDK.
Run emcc --version to verify your installation.

Check your Node.js version:

node -v
# Expected output:
# v14.18.2

1. Write the C Source

Create a file named helloworld.c with the following contents:

#include <stdio.h>

int main() {
    printf("Hello World\n");
    return 0;
}

2. Compile to WASM for Node.js

Use Emscripten’s emcc compiler to generate both the WebAssembly binary and the JavaScript loader:

emcc /path/to/helloworld.c -o /path/to/helloworld.js

This command produces:

File	Description
helloworld.js	JavaScript “glue” code that locates, loads, and runs the WASM asset
helloworld.wasm	Compiled WebAssembly module

The top of helloworld.js looks like this:

var Module = typeof Module != 'undefined' ? Module : {};
// …glue code to locate and instantiate helloworld.wasm…

3. Execute the WASM Module in Node.js

Run your generated loader script with Node:

node /path/to/helloworld.js
# Output:
# Hello World

That’s all! You’ve successfully compiled a C program into WASM and executed it on the server with Node.js.

Links and References

Watch Video

Introduction to Cloud Native WASM

Exploring WebAssembly WASM and Docker

​Prerequisites

​1. Write the C Source

​2. Compile to WASM for Node.js

​3. Execute the WASM Module in Node.js

​Links and References

Watch Video

Prerequisites

1. Write the C Source

2. Compile to WASM for Node.js

3. Execute the WASM Module in Node.js

Links and References