[udp]

When I ported my frontend to TypeScript I swapped out the whole observ* suite for my own typed observables. Sure, some of the components are too specific to replace trivially, but then those most likely aren't the ones you're interested in replacing.

Decomposing your code into modules is step one. Making the interface between your modules generic enough to easily replace is the next problem, but if your code is a monolithic blob in the first place that's not going to be possible.

My main issue with modularity in JavaScript is the lack of strict typing, because you won't know if your interface fits correctly until runtime - which is why I've been looking into TypeScript and Elm recently.

[igl]

Or you could just have written a .ts.d file?