Building

This section describes everything required to build and run Wasmtime.

Prerequisites

Before we can actually build Wasmtime, we'll need to make sure these things areinstalled first.

Git Submodules

The Wasmtime repository contains a number of git submodules. To build Wasmtimeand most other crates in the repository, you have to ensure that those areinitialized with this command:

git submodule update --init

The Rust Toolchain

Install the Rust toolchain here. Thisincludesrustup,cargo,rustc, etc...

libclang (optional)

Thewasmtime-fuzzing crate transitively depends onbindgen, which requiresthat your system has alibclang installed. Therefore, if you want to hack onWasmtime's fuzzing infrastructure, you'll needlibclang.Details on how togetlibclang and make it available forbindgen arehere.

Building thewasmtime CLI

To make an unoptimized, debug build of thewasmtime CLI tool, go to the rootof the repository and run this command:

cargo build

The built executable will be located attarget/debug/wasmtime.

To make an optimized build, run this command in the root of the repository:

cargo build --release

The built executable will be located attarget/release/wasmtime.

You can also build and run a localwasmtime CLI by replacingcargo buildwithcargo run.

Building the Wasmtime C API

Seecrates/c-api/README.mdfor details.

Building Other Wasmtime Crates

You can build any of the Wasmtime crates by appending-p wasmtime-whatever tothecargo build invocation. For example, to build thewasmtime-environ crate,execute this command:

cargo build -p wasmtime-environ

Alternatively, you cancd into the crate's directory, and runcargo buildthere, without needing to supply the-p flag:

cd crates/environ/cargo build