cnfast

cnfast is a high-performance JavaScript replacement for the common cn utility used in Tailwind CSS projects. It combines conditional class values and resolves conflicting Tailwind classes while preserving byte-identical output with tailwind-merge. The package exposes cn, clsx, twMerge, and twJoin through a familiar API. Existing clsx, classnames, tailwind-merge, and shadcn/ui projects can migrate with minimal or automated changes. Caching and an optimized merge engine improve performance during repeated renders and component-heavy workloads. It supports standard function calls and tagged templates and is distributed as a compact npm package.