Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires psr/log ^2, found psr/log[2.0.0] but these were not loaded, likely because it conflicts with another require. Problem 2 - phpdocumentor/reflection 5.2.0 requires psr/log ~1.0 -> found psr/log[1.0.0, ..., 1.1.4] but it conflicts with your root composer.json require (^2). - donatj/mddoc v0.10.1 requires phpdocumentor/reflection ~5.2.0 -> satisfiable by phpdocumentor/reflection[5.2.0]. - donatj/mddoc is locked to version v0.10.1 and an update of this package was not requested.