I like crystal_lib. Very useful tool. To the core team, please continue your development.
If you are making a C binding and want to parse C headers, there is a tool called c2ffi. This tool only outputs a JSON file. However, by reading the output JSON, you may be able to generate and validate bindings.
crystal_lib is an experiment. It yielded practical results and I’m sure it can utilized for many use cases. However, it’s currently not advancing any further to reach a productive stage. There are limitations to this approach for generating lib bindings, and there are more promising approaches such as [RFC] C bindings helper · Issue #8307 · crystal-lang/crystal · GitHub.
At this stage, crystal_lib is not a priority of the Core Team. We do not have the resources to continue these efforts. But any help is welcome. We’d be happy to transfer this project to a new maintainer.