FWIW, asciinema is something that's been posted and discussed before...what's new is that the player can be self-hosted, as it consists of nothing more than a JS and CSS file. This means the recording can be exported as a flat JSON file. Previously, the only option was to host the replay on the asciinema server: http://blog.asciinema.org/post/self-hosting/
As someone who writes a few tutorials on programming...this is a godsend. Novices need to be able to see how the code works interactively...but it's a real pain in the ass to render animated GIFs. Asciinema creates something that is lightweight and just text, for all the flexibility and portability that allows.
Another option is my own <tty-player> (http://tty-player.chrismorgan.info/), which takes the approach of being a drop-in replacement for a <video> taking as its source format that of tools like termrec (with no modifications).
As someone who writes a few tutorials on programming...this is a godsend. Novices need to be able to see how the code works interactively...but it's a real pain in the ass to render animated GIFs. Asciinema creates something that is lightweight and just text, for all the flexibility and portability that allows.