配置composer.json

{
    "repositories": {
        "packagist": {
            "type": "composer",
            "url": "https://packagist.phpcomposer.com"
        }
    },
    "require": {
        "php": "<=5.3.29"    }}
之后执行composer require xxx/xxx包安装时，composer会自动安装php5.3.29版本支持的包版本