y-combinator-izing curried angular router

i've recently gone a bit mad with wanting to turn everything i touch into functional code & this being my latest foray, a thing that creates a flat routing structure from nested functions and stuff:

from this code

const APP_ROUTES: Routes = new AppRouter()
.register(``, FeedComponent, LoggedInGuard)
.register(`watch`, PerformanceWatchComponent, LoggedInGuard)
.register(`search`, CatalogComponent, LoggedInGuard)
.register(`verified`, VerifiedComponent)
.register(`user/@:${RP.UserId}`, ProfileComponent, LoggedInGuard)
.register(`performance/:${RP.PerformanceId}`, PerformanceComponent, LoggedInGuard)
.pushRouter((r) => r.register(`host/@:${RP.HostId}`, HostComponent, LoggedInGuard))
.register(`performances`, HostPerformancesComponent, LoggedInGuard)
.pushRouter((r) => r.register(`:${RP.PerformanceId}`, HostPerformancesComponent, LoggedInGuard))
.register(`watch`, HostPerformancesComponent, LoggedInGuard)
.register(`ui`, TestbedComponent)

all the fp goodness man could ever wish for, i mean look at that supple tree...and the y-combinator itself you may ask?

export default class AppRouter {
// ...

apply(): Routes {
return Y((r: (x: AppRouter) => Routes) => (n) => {
return [
...n.routes.map((rs) => ({ ...rs, path: n.root + rs.path })),
...n.routers.reduce((acc, curr) => {
// omgggg
return [...acc, ...r(curr)];
}, []),

gone are the days of stupid objects and arrays