Most supply-chain attacks using Ruby's package hosting site "exploit a narrow window," according to a new blog post form Ruby core maintainer Hiroshi Shibata.

So its packaging-managing Bundler tool now offers a filter that blocks new version until it's been public "for at least N days. Releases too new to have been scrutinized are passed over in favor of ones that have aged past the window."

The feature was designed in the open, drawing on how other ecosystems approach the same problem. It is opt-in, and complements rather than replaces existing defenses like mandatory 2FA and trusted publishing... Cooldown is unset by default, so a project without it keeps resolving to the newest version...