> ## Documentation Index
> Fetch the complete documentation index at: https://codspeed.io/docs/llms.txt
> Use this file to discover all available pages before exploring further.
# divan compatibility layer documentation
> A compatibility layer for `divan`
export const BuildkiteIcon = props => ;
export const GitLabIcon = props => ;
export const GitHubIcon = props => ;
## Overview
`codspeed-divan-compat` is a Divan compatibility layer for CodSpeed that allows
seamless integration of Divan benchmarks with CodSpeed performance measurement.
This crate acts as a drop-in replacement for Divan, maintaining your existing
benchmark code while enabling CodSpeed integration.
Divan is the **recommended benchmarking framework** for Rust when using
CodSpeed due to its modern design and excellent performance characteristics.
## Installation
```sh theme={null}
cargo add --dev codspeed-divan-compat --rename divan
```
This will install the `codspeed-divan-compat` crate and rename it to `divan` in your `Cargo.toml`.
This way, you can keep your existing imports and the compatibility layer will take care of the rest.
Using the compatibility layer won't change the behavior of your benchmark suite
and divan will still run it as usual.
If you prefer, you can also install `codspeed-divan-compat` as is and change
your imports to use this new crate name.
## Usage
Let's start with the example from the
[divan documentation](https://docs.rs/divan/0.1.17/divan/index.html#getting-started),
creating a benchmark suite for the Fibonacci function (in
`benches/my_benchmark.rs`):
```rust theme={null}
fn main() {
// Run registered benchmarks.
divan::main();
}
// Register a `fibonacci` function and benchmark it over multiple cases.
#[divan::bench(args = [1, 2, 4, 8, 16, 32])]
fn fibonacci(n: u64) -> u64 {
if n <= 1 {
1
} else {
fibonacci(n - 2) + fibonacci(n - 1)
}
}
```
The last step in creating the divan benchmark is to add the new benchmark target
in your `Cargo.toml`:
```toml title="Cargo.toml" theme={null}
[[bench]]
name = "my_benchmark"
harness = false
```
And that's it! You can now run your benchmark suite with `cargo-codspeed`:
```shellsession title=terminal icon="square-terminal" theme={null}
$ cargo codspeed build
Finished release [optimized] target(s) in 0.12s
Finished built 1 benchmark suite(s)
$ cargo codspeed run
Collected 1 benchmark suite(s) to run
Running my_benchmark
NOTICE: codspeed is enabled, but no performance measurement will be made since it's running in an unknown environment.
Checked: benches/my_benchmark.rs::fibonacci[1]
Checked: benches/my_benchmark.rs::fibonacci[2]
Checked: benches/my_benchmark.rs::fibonacci[4]
Checked: benches/my_benchmark.rs::fibonacci[8]
Checked: benches/my_benchmark.rs::fibonacci[16]
Checked: benches/my_benchmark.rs::fibonacci[32]
Done running my_benchmark
Finished running 1 benchmark suite(s)
```
## Compatibility
### Not (yet) supported
* [`divan::bench(crate = xxx)`](https://docs.rs/divan/latest/divan/attr.bench.html#crate):
due to how the compatibility layer works internally, we do not plan to support
this feature.
* [`divan::bench_group`](https://docs.rs/divan/latest/divan/attr.bench_group.html):
we do not support benchmark grouping yet, if you need it don't hesitate to
create an issue.
## Resources
* [Official divan documentation](https://docs.rs/divan/latest/divan/index.html)
* [Official divan GitHub repository](https://github.com/nvzqz/divan)
