Ruby applications can be broadly split into two categories: those that run for a short period and those that stick around for a while. Optimizing performance for one often comes at the expense of the other. Over the years, alternative Ruby implementations have demonstrated remarkable performance gains for long-lived applications -- so-called peak performance -- but often lose out to MRI for short-lived applications. In this talk, I'll introduce the SubstrateVM and show how we use it to massively improve TruffleRuby's startup time with minimal impact on peak performance.