ISR has been a game-changer for HashiCorp, enabling them to deliver faster changes and better site performance by leveraging the power of server-side code and on-demand ISR. With traditional static site generation, build times could be hours-long, but ISR makes this process much faster and more efficient by enabling developers to use SSG on a per-page basis, without needing to rebuild the entire site. On-demand ISR allows for manual purge of the Next.js cache for specific pages, making it easier to update sites, particularly when content is created or updated from a headless CMS. By leveraging API calls, teams can get near-instant updates without relying on deploy triggers, which would re-generate unchanged pages. HashiCorp's engineers use ISR and on-demand ISR to iterate quickly while maintaining flexible sites and apps. With the introduction of on-demand ISR in Next.js 12.1, developers can now ship large-scale projects with faster build times and better site performance.