On zenerre, built with rDJENKINSSLAVES:
$ php -r "echo ini_get('memory_limit').PHP_EOL;" 128M
That triggers a Composer out of memory issue at https://ci.nasqueron.org/job/test-auth-grove-phab/6/console
[exec] Fatal error: Allowed memory size of 1610612736 bytes exhausted (tried to allocate 67108864 bytes) in phar:///opt/composer.phar/src/Composer/DependencyResolver/Solver.php on line 220
(rGROVE dependencies will probably be easier to resolve if we upgrade Laravel)
On WindRiver, I had the same issue but then were able to run composer install with 2G memory limit.