I keep having issues with updating my composer dependencies. The moment I start, I see
Loading composer repositories with package information
Updating dependencies (including require-dev)
Killed
What's causing this?
It's probably running out of memory, so the OS kills the proces. You might get more information from the syslog. Try adding SWAP to your Linode or using a VPS with more memory.
See already asked question here: Composer killed while updating