Fatal error running the example in the docs

[ACXgit]

Hello everyone, I get this error when I try to run the example server in the docs:

Fatal error: Declaration of class@anonymous::onError(int $code, Icicle\Socket\Socket $socket) must be compatible with Icicle\Http\Server\RequestHandler::onError($code, Icicle\Socket\Socket $socket) in /usr/local/src/icicle/bin/server on line 11

My composer.json:

{
    "require": {
        "icicleio/http": "^0.3.0"
    }
}