# Wasmtime's C API
## API Documentation
[The API documentation for the Wasmtime C library is hosted
here.](https://bytecodealliance.github.io/wasmtime/c-api/).
## Using in a C Project
### Using a Pre-Built Static or Dynamic Library
Each release on Wasmtime's [GitHub Releases
page](https://github.com/bytecodealliance/wasmtime/releases) has pre-built
binaries for both static and dynamic libraries for a variety of architectures
and operating systems attached, as well as header files you can include.
### Building Wasmtime's C API from Source
To use Wasmtime from a C or C++ project, you must have
[CMake](https://cmake.org/) and [a Rust
toolchain](https://www.rust-lang.org/tools/install) installed.
From the root of the Wasmtime repository, run the following commands:
```
$ cmake -S crates/c-api -B target/c-api --install-prefix "$(pwd)/artifacts"
$ cmake --build target/c-api
$ cmake --install target/c-api
```
These commands will produce the following files:
* `artifacts/lib/libwasmtime.{a,lib}`: Static Wasmtime library. Exact extension
depends on your operating system.
* `artifacts/lib/libwasmtime.{so,dylib,dll}`: Dynamic Wasmtime library. Exact
extension depends on your operating system.
* `artifacts/include/**.h`: Header files for working with Wasmtime.
## Using in a Rust Project
If you have a Rust crate that contains bindings to a C or C++ library that uses Wasmtime, you can link the Wasmtime C API using Cargo.
1. Add a dependency on the `wasmtime-c-api-impl` crate to your `Cargo.toml`. Note that package name differs from the library name.
```toml
[dependencies]
wasmtime-c-api = { version = "16.0.0", package = "wasmtime-c-api-impl" }
```
2. In your `build.rs` file, when compiling your C/C++ source code, add the C `wasmtime-c-api` headers to the include path:
```rust
fn main() {
let mut cfg = cc::Build::new();
// Add to the include path the wasmtime headers and the standard
// Wasm C API headers.
cfg
.include(std::env::var("DEP_WASMTIME_C_API_INCLUDE").unwrap());
// Compile your C code.
cfg
.file("src/your_c_code.c")
.compile("your_library");
}
```