Grav vs ProcessWire: What are the differences?
Grav: A modern open source flat-file CMS. It is a free, open-source and self-hosted content management system (CMS) based on the PHP programming language and Symfony web application framework. It uses a flat file database for both backend and frontend. It is more widely used, and growing at a faster rate, than other leading flat-file CMS competitors; ProcessWire: CMS with a jQuery inspired content API. ProcessWire is an open source content management system (CMS) and web application framework aimed at the needs of designers, developers and their clients. ProcessWire gives you more control over your fields, templates and markup than other platforms, and provides a powerful template system that works the way you do.
Grav and ProcessWire can be primarily classified as "Self-Hosted Blogging / CMS" tools.
Grav and ProcessWire are both open source tools. It seems that Grav with 11.2K GitHub stars and 1.13K forks on GitHub has more adoption than ProcessWire with 746 GitHub stars and 226 GitHub forks.
According to the StackShare community, ProcessWire has a broader approval, being mentioned in 5 company stacks & 25 developers stacks; compared to Grav, which is listed in 5 company stacks and 5 developer stacks.