Conky is a free, light-weight system monitor for X, that displays any kind of information on your desktop. Conky can display more than 300 built-in objects, including support for a plethora of OS stats, support for many popular music players, and Lua scripting. Conky can display information either as text, or using simple progress bars and graph widgets, with different fonts and colours. With some clever configuration you can use Conky to make some amazing system dashboards.

Runs on Linux, FreeBSD, OpenBSD, DragonFlyBSD, NetBSD, Solaris, Haiku, and macOS.

Documentation: https://github.com/brndnmtthws/conky/wiki

Fast, typo tolerant search engine for building delightful search experiences. Has an API and a number of protocol modules for different languages. Written in C and C++.

Designed for people who don't want to fuck with Elasticsearch, they just want a document search engine. Lightweight, powerful, scalable. Tries to have smart defaults. Single executable. Uses far less memory than the usual Java-based search systems do. Tries to be flexible so you can build the search engine you need.

Looks like you define a JSON document with the stuff you want to be able to search and throw it over to the engine. Means you'll need to write some front-end tooling to extract the data you want to index, which might not be that big a deal. It could just be some shell scripts.