One Monorepo, Two Outputs: How I Eliminated Duplicate Starter Templates

Part 2 of the Building create-notils series. In my previous article , I explained why I stopped copy-pasting repositories and started building my own project scaffolding tool. However, one major architectural problem remained: I wanted create-notils to support both of these primary project structures. A standalone Next.js application: my-app/ ├── src/ ├── public/ ├── package.json └── components.json And a Turborepo monorepo: my-app/ ├── apps/ │ └── app/ ├── packages/ │ ├── ui/ │ └── config/ ├── turbo.json └── package.json At first glance, the obvious solution is to maintain two separate templates—one for standalone and one for monorepo. Problem solved, right? Except... it isn't. The Hidden Cost of Multiple Templates Every starter template starts out identical. Then one day, you fix a subtle bug in one template and forget to update the other. A week later, you upgrade Next.js in one repository before getting around to the second. A month later, you improve your UI package and find yourself manually copying files back and forth between folders. Eventually, the templates slowly drift apart. The true cost isn't creating templates; the cost is maintaining them forever. What Actually Changes? When I sat down and compared the two project layouts side by side, surprisingly little was different. The actual application code, UI components, theming, and utility functions were 100% identical. The only real differences were the structural project boundaries: Concern Monorepo Standalone UI Package packages/ui src/components/ui Utilities @notils/ui/lib/utils @/lib/utils Configuration Shared workspace package Local configuration Package Manifests Multiple ( package.json files) Single root manifest Workspace Tooling Present ( turbo.json , workspaces) Removed entirely Everything else was effectively the exact same code. That single observation changed the entire architecture of create-notils . A Different Approach: The Canonical Source of Truth Instead of maintaining two templates, I