It can be installed like a plugin, but it has a server component too. So installing it into a single file wiki will not really help here.
You may be interested in: Use WebDAV for saving a single file wiki, which is production ready, with it’s own complexities. It describes several methods to save single-file wikis on a home-network using WebDav.
You are right MWS is a server addOn, that will activate an SQLite database file as a data-store.
In contrast to the “file based store” of the standard Node.js-server
SQLite has some properties that align very well with the TW philosophy. Especially “compatibility”
From the SQLite homepage:
What Is SQLite?
SQLite is a C-language library that implements a small, fast, self-contained, high-reliability, full-featured, SQL database engine. SQLite is the most used database engine in the world. SQLite is built into all mobile phones and most computers and comes bundled inside countless other applications that people use every day. More Information…
I did highlight some elements (and removed the links), that are almost the same wording that we use for our single file TiddlyWiki’s.
The SQLite database also is a single-file, where the developers want to guarantee compatibility at least up to 2050.
The SQLite file format is stable, cross-platform, and backwards compatible and the developers pledge to keep it that way through the year 2050. SQLite database files are commonly used as containers to transfer rich content between systems [[1]] [[2]] [[3]] and as a long-term archival format for data [[4]]. There are over 1 trillion (1e12) SQLite databases in active use [[5]].
SQLite source code is in the public-domain and is free to everyone to use for any purpose.
As I wrote at the beginning of this post. You may be interested in the WebDav servers and may be also in the Node.js server, which are well tested.
I think the feature set of MWS is already very clear, since it is very very similar to what we had for TiddlyWeb and TiddlySpace (which are discussed in the video I did mention) – Only the technology which is at our hand now, has evolved quite a bit.