Your requirements could not be resolved to an installable set of packages. Problem 1 - phpdocumentor/flyfinder 1.1.0 requires league/flysystem ^1.0 -> satisfiable by league/flysystem[1.0.0, ..., 1.1.10]. - You can only install one version of a package, so only one of these can be installed: league/flysystem[1.0.0, ..., 1.1.10, 3.0.0, ..., 3.28.0]. - phpdocumentor/guides 1.x-dev requires league/flysystem ^3.28 -> satisfiable by league/flysystem[3.28.0]. - phpdocumentor/guides 1.x-dev requires phpdocumentor/flyfinder ^1.1 -> satisfiable by phpdocumentor/flyfinder[1.1.0]. - Root composer.json requires phpdocumentor/guides ^2.0@dev || ^1.0 -> satisfiable by phpdocumentor/guides[1.x-dev]. Use the option --with-all-dependencies (-W) to allow upgrades, downgrades and removals for packages currently locked to specific versions.