Freelancers keep rebuilding the same handoff: developer builds the site, client breaks the layout trying to change a headline. Primo is an open-source CMS built for that handoff, where developers define reusable blocks and page types, and clients edit text, images, and links directly on the rendered page without touching the structure underneath. Multiple client sites live in one dashboard, organized into groups with a domain each, and publishing generates fast static HTML you can serve from Primo itself or export to another host. The whole site also exists as structured local files, so you or an AI coding agent can pull a site down, edit its blocks and fields in your normal tools, push changes back with revision checks that protect client edits, and publish when ready. Editors can add child pages and reorder the blocks a page type allows, while developers keep control of block code, field schemas, layouts, and roles. A marketplace of starters gives new projects a running start across restaurants, portfolios, practices, and shops. One small server binary with embedded storage runs the CMS and serves the published sites, which suits an agency hosting a dozen client sites on one machine. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.