Here’s an incomplete list of the stuff I made and am working on. All of it is freely available as open source under the MIT license.
The following pieces of software have been around for a significant amount of time, are battle-tested and considered stable. You can rely on them.
adsf is a web server that you can launch instantly in any directory.
cri helps build command-line applications in Ruby.
ddmemoize implements memoization for Ruby.
ddmetrics records and analyses runtime measurements for Ruby apps.
ddplugin is a Ruby library for handling plugins.
nanoc is a fast and flexible static-site generator.
slow_enumerator_tools supports merging, buffering, … Ruby enumerators.
The following pieces of software are work in progress. Their APIs are unstable, they are buggy, but… they are probably more exciting than the production-ready ones. Play around with them, but don’t use them for real work.
d★mark is a semantically-rich markup language for prose.
d★parse is a parser combinator library for Ruby.
d★stream allows writing stream-processing code in Ruby.
glove is a game engine for Crystal.
rcpu is a VM emulator and assembler written in Crystal.