Spellweavers.gg project consists of two parts: an open-source version of the core game engine that strives to support multiple rulesets (spellbooks), and a web interface built on top of this engine (this website), which is currently in closed beta stage of development.
Please request access, submit your feedback and discuss this project at Spellweavers subreddit.
In 1977 Richard A. Bartle created a pencil-and-paper game Spellbinder (a.k.a. Waving Hands). In this game players cast various spells by creating sequences of gestures with their two hands. You can read more at Bartle's website and at Wikipedia.
The game had a number of implementations (some of which are mentioned in the articles above), some with their own rulesets (spellbooks). The early ones, including a X-windows version by Andrew Plotkin, a Java Applet version by Joseph M. Sims, and a portable rewrite of Andrew Plotkin's X-windows version by Dennis Taylor, were implementing the initial Spellbinder spellbook.
A notable step in spellbook evolution came with The FireTop Mountain, a play-by-email version that was created around 1998 (it is still technically available today, as of January 2026). Being not only a client, but also a website with a repository of previous games, it allowed for community building and balance discussions. As a result, their "Main" ruleset is significantly different from the original SpellBinder - Fire and Ice elementals are introduced, Amnesia and Fear make monsters skip their attacks, Anti-spell is SPFP (instead of SPF), TimeStop receives a second flow of SPPFD.
Probably the most popular version during the last 20+ years is the web version of the game named Warlocks and implemented by RavenBlack back in early 2000s. This version also maintained games archive for some time and the community discussions resulted in a rebalance of two mindspells (Paralysis F to C instead of C to F, and Maladroitness replacing Confusion). Further competitive activities and discussions of alternative rulesets (like ParaDFD) were taking place in 00's at Slartucker's Refuge.
Around 2015, another web-based version was created by Naigsa at mortalspell.com. It used Warlocks' ParaFC Maladroit ruleset, but also had additional features such as games with an AI bot. Unfortunately, this version was taken down in early 2020's.
In early 2020s a mobile game client for Warlocks was introduced by Galbarad; it acts as a 3rd party front-end to Warlocks web version, but, probably, it has to do by parsing Warlocks HTML output, which introduces some other challenges and limits it's functionality.