Kind of does does rewrites for SvelteKit

index.svelte

<script lang="ts" context="module">
    import { rewriteLoad } from "./RewriteLoader.svelte"
    import { load as loadCareers } from "./careers.svelte"
    import { load as loadAbout } from "./about.svelte"
    import { load as loadContact } from "./contact.svelte"

    enum PageRoute {
        careers,
        about,
        contact
    }

    export const load = rewriteLoad([
        { id: PageRoute.careers, load: loadCareers },
        { id: PageRoute.about, load: loadAbout },
        { id: PageRoute.contact, load: loadContact }
    ])
</script>

<script lang="ts">
    import { RewriteLoader } from "$lib/components"

    export let id: PageRoute
    export let props: any

    function resolve(id: PageRoute) {
        switch (id) {
            case PageRoute.careers:
                return import("./careers.svelte")
            case PageRoute.about:
                return import("./about.svelte")
            case PageRoute.contact:
                return import("./contact.svelte")
            default:
                throw new Error(`Unknown id ${id}`)
        }
    }
</script>

<RewriteLoader {resolve} {id} {props} />

RewriteLoader.svelte

<script context="module" lang="ts">
    import type { Load, LoadInput, LoadOutput } from "@sveltejs/kit"

    export interface Route {
        id: any
        load: Load
    }

    export function rewriteLoad(routes: Route[]): Load {
        return async input => {
            let id: any
            let output: LoadOutput

            for (const route of routes) {
                output = await route.load(input)
                if (output) {
                    id = route.id
                    break
                }
            }

            if (!id) return

            return {
                ...output,
                props: {
                    id,
                    props: output.props
                }
            }
        }
    }
</script>

<script lang="ts">
    import type { SvelteComponent } from "svelte"
    export let id: any
    export let props: any
    export let resolve: (id: any) => Promise<{ default: SvelteComponent }>
</script>

{#await resolve(id) then module}
    <svelte:component this={module?.default} {...props ?? {}} />
{/await}