Do you see any other solutions in the same domain as Stopify? Another method that might provide a way to keep UI unblocked but still have user executable code?
If you need the user code to execute on the main thread, then unfortunately I am aware of none besides bundling your own tailored system.
Pyret used to use its own runtime system [0] but Stopify was created in part to replace it due to the maintenance burden and complexity of "vanilla" JS interoperability.
Pyret used to use its own runtime system [0] but Stopify was created in part to replace it due to the maintenance burden and complexity of "vanilla" JS interoperability.
[0] https://www.pyret.org/docs/latest/s_running.html