The CBTTape has been around since the 1970's and has evolved from tape reels to CDROMs to DVD to a website (and soon to GitHub). It can be found at https://www.cbttape.org and currently (as of the date of this post) has 1,045 files containing from one to dozens of open-source contributions.
One challenge that existed was difficulty in finding just the right tool to either (a) use, or (b) learn from. This was solved by the release of the CBTVIEW ISPF dialog - also known as The Official CBT ISPF Dialog (some call it OCD).
See this short video to see how to use it https://youtu.be/pF-1r05cF5E
You can download it from File 043 at https://www.cbttape.org or from https://github.com/lbdyck/cbtview.
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Lionel B. Dyck <><
IBM z Systems Champion
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