If you want to use Composer 2 with Symfony 3, you can use that buundle.

In your composer.json, replace: ```

"sensio/distribution-bundle": "^5.0",

```

"sensio/distribution-bundle": "dev-master",

```

And add the following in your repositories:

``` "repositories": [

{

"type": "vcs", "url": "https://github.com/ninsuo/SensioDistributionBundle-composer2"

}