I'm planning to list the major tasks for Sinatra v3.0.0.

Improve performance by especially focusing on our routing algorithm.

I'd love to improve the performance.
As a PoC, I have implemented pendragon and its radix tree implementation.
In fact, we need to implement original pure Ruby radix tree and its searching method in Sinatra. But there is a possibility of reducing the cost. In addition, roda also has an interesting way for improving routing performance.

Refactor our code base (especially sinatra/base.rb)

I have often seen developers whose base.rb code is awkward and gives up contributions.
The actual Sinatra's logic is not very complicated, but it seems that the code base integrated into one current file has the effect of making it feel more difficult than the actual difficulty.
Regarding this, I want to simplify the implementation by dividing the file properly and correcting the inappropriate specification.

Other topics, and opinions regarding the above topics are welcome.