Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires ramsey/composer-repl ^1.4 -> satisfiable by ramsey/composer-repl[1.4.0, 1.4.1, 1.5.0]. - Root composer.json requires spatie/phpunit-snapshot-assertions ^4.2 -> satisfiable by spatie/phpunit-snapshot-assertions[4.2.0, ..., v4.x-dev]. - Root composer.json requires vimeo/psalm ~6.1.0 -> satisfiable by vimeo/psalm[6.1.0]. - ramsey/composer-repl 1.4.0 requires ramsey/composer-repl-lib ^1.0 -> satisfiable by ramsey/composer-repl-lib[1.0.0, ..., 1.3.0]. - ramsey/composer-repl 1.4.1 requires ramsey/composer-repl-lib ^1.1 -> satisfiable by ramsey/composer-repl-lib[1.1.0, 1.2.0, 1.3.0]. - ramsey/composer-repl 1.5.0 requires ramsey/composer-repl-lib ^1.2 -> satisfiable by ramsey/composer-repl-lib[1.2.0, 1.3.0]. - ramsey/composer-repl-lib[1.0.0, ..., 1.1.0] require psy/psysh ^0.11.0 -> satisfiable by psy/psysh[v0.11.0, ..., 0.11.x-dev]. - ramsey/composer-repl-lib 1.2.0 requires psy/psysh ^0.11.12 -> satisfiable by psy/psysh[v0.11.12, ..., 0.11.x-dev]. - Conclusion: don't install psy/psysh v0.11.1 (conflict analysis result) - Conclusion: don't install psy/psysh v0.11.22 (conflict analysis result) - Conclusion: don't install ramsey/composer-repl-lib 1.3.0 (conflict analysis result)