Are there any circumstances where a company can reasonably go dark for a week?
If it is an acquisition it's pretty disrepectful of people investing in their solution.
Startups can't afford that. Therefore they should use older technology until they grow big enough to tank the damage.
You've got to realise that for enterprise software, there's $10 sales, $100 sales, $1,000 sales ... and then $1,000,000 sales. At the top level, you're looking at entities who have the resources, and occasionally the motivation, to bring product entirely in-house. It might not be their first choice, but it's an option, and quite likely something they've already considered when negotiating for services.
Didn't the same problem happen to the CloudFlare with LuaJIT where they would like to hire guys that worked on it but couldn't ?
Things can get difficult in some situations, we're all human. But Joyent going bankrupt wouldn't mean the end of Node. But where is Datomic without Cognitent?