Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires react-parallel/pool-tests dev-93e4215426572663f44e85c4d49636fbb1f9ab6a -> satisfiable by react-parallel/pool-tests[dev-93e4215426572663f44e85c4d49636fbb1f9ab6a]. - react-parallel/pool-tests dev-93e4215426572663f44e85c4d49636fbb1f9ab6a requires react-parallel/contracts ^2@dev -> found react-parallel/contracts[2.x-dev] but it does not match your minimum-stability.

Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires react-parallel/pool-tests dev-49/merge, found react-parallel/pool-tests[dev-93e4215426572663f44e85c4d49636fbb1f9ab6a] but it does not match the constraint.