What tool can be used to build a custom internal firm portal, client portal, or niche landing pages without traditional web development?

One member built an internal staff portal, a client portal, an onboarding hub, and niche landing pages (e.g., for a therapist-CPA niche) using a platform called Fillout (fillout.com), which started as a form-building company and expanded into 'vibe coding' through a companion product called Zite (with a Z). Zite lets you build an app, a database, or a form directly through AI-assisted development. The member noted the framework their client-facing side sits on is now called 'Assembly' (formerly Copilot), which is used for client connections, while the actual custom portal and websites were built separately in Fillout/Zite.