Having developed on that platform for a long time, I will say that It Depends. Clearly you shouldn't dust off a Ruby 1.8.7 app and deploy it to prod, but what

Having developed on that platform for a long time, I will say that It Depends. Clearly you shouldn't dust off a Ruby 1.8.7 app and deploy it to prod, but what would be the harm in using a script you wrote in 2012, say, to batch process a CSV to JSON? In fact, the project you're dusting off might just be an old revision of your current app that you already ported (over the years) to current standards, but you thought you wouldn't need that script so you deleted it 7 years ago rather than keep it up to date. if you could check out the old tag and run the script intact, that would be ideal.