Vercel Workflow Kit takes a very different approach. Lack of step IDs (which makes them worse at handling code changes), compilation step, more opinionated about backends ("worlds", as they call them). Vercel Workflow Kit has magic that admittedly makes it a little easier to get started, but that magic causes problems when you want a mature product.

Cloudflare Workflows are actually complementary to StepKit! We'll soon release an adapter that lets you define StepKit workflows that run as Cloudflare Workflows. We have a POC in `packages/cloudflare` in our repo