Getting Started

You can install the Wasmer Standalone runtime by following the instructions below:

If you haven't done so already, install the Wasmer Command Line Interface (CLI) for macOS/Linux:

curl https://get.wasmer.io -sSfL | sh

Or you can use this PowerShell command if you are in Windows:

iwr https://win.wasmer.io -useb | iex

Note: All Wasmer executables can be found on out Github Releases Page.

Wasmer needs some requirements to be met to run properly. On Linux, you will have to be sure you have a compatible libc/libstdc++. Wasmer expects the following ABI versions to be available:

  • GLIBC: >= 2.27

  • GLIBCXX: >= 3.4.21

To verify if your environments provides the correct versions you can use the commands below:

LIBC_PATH=$(gcc --print-file-name=libc.so.6)
strings $LIBC_PATH | grep -e '^GLIBC'
​
LIBCXX_PATH=$(gcc --print-file-name=libstdc++.so.6)
strings $LIBCXX_PATH | grep -e '^GLIBCXX'

Note that you will need to install gcc and binutils for these commands to work.

If you can't match these requirements you will have to build Wasmer manually.

Once the Wasmer CLI is installed, you can run Wasm modules from the command line!

To do this, you want to find a Wasm Module compiled down to an ABI that the Wasmer runtime supports, such as WASI or Emscripten. For instance, we can search for a module on WAPM, and go to the module page, and then click on the "Browse modules" tab.

In this example, we will be using QuickJS compiled to WebAssembly. To do this we download the module from WAPM, and then run:

wasmer qjs.wasm

Which should bring up the QuickJS prompt which you can then interact with. See an example below:

Next, we can take a look at the command line flags and arguments for the CLI, for more advanced usage.