Indeed. I had similar angst through the week following the Block Party and I was mentally pacing back and forth contemplating the possibilities. And imagine those of us waiting for this since 2019 as evidenced by threads like this one. But with this energy, I was able to make some progress before my beta request was accepted.
For example - given this simple code snippet I was able to deduce a general understanding of Packs and design a statistical outlier identifier; a simple formula that when given a list of numbers, it classifies the rows as normal or abnormal. Using the free Google Apps Script framework I was able to quickly create a test harness that mimics the addFormula() method and fully develop the [future] pack’s behavior. Once I was in, I tested my GAS-created pack facsimile in a few minutes and it worked.
The vision of an integrated Javascript framework in Coda was the first thing that came to mind in 2019 when I created my first Coda document and used formulas. I knew there was an extensibility issue but with the lineage of the creators, I also knew what the future might look like – and here it is today.
The current Packs Studio is not a pathway that magically eliminates all Coda constraints, but it is a pretty amazing start and you can begin to build custom formulas today - long before you have access. It’s just javascript in an SDK environment that is [somewhat] documented - you are free to build and shore up those javascript skills today.