`npm run dev` -> `TypeError: routeSegments.at is not a function`

[timothymalcham]

Wanted to try out the stack, installed via the getting-started.md instructions. Ran the setup command, and then tried to boot up the server (without touching any files or code) and got this:

➜ npm run dev

> dev
> remix dev -c "npm run dev:server" --no-restart

TypeError: routeSegments.at is not a function
    at getRouteSegments (/Users/timothymalcham/dev/uu/node_modules/remix-flat-routes/dist/index.js:356:23)
    at getRouteInfo (/Users/timothymalcham/dev/uu/node_modules/remix-flat-routes/dist/index.js:210:25)
    at /Users/timothymalcham/dev/uu/node_modules/remix-flat-routes/dist/index.js:119:33
    at defaultVisitFiles (/Users/timothymalcham/dev/uu/node_modules/remix-flat-routes/dist/index.js:382:13)
    at defaultVisitFiles (/Users/timothymalcham/dev/uu/node_modules/remix-flat-routes/dist/index.js:379:13)
    at _flatRoutes (/Users/timothymalcham/dev/uu/node_modules/remix-flat-routes/dist/index.js:113:9)
    at flatRoutes (/Users/timothymalcham/dev/uu/node_modules/remix-flat-routes/dist/index.js:44:20)
    at Object.routes (file:///Users/timothymalcham/dev/uu/remix.config.js:22:10)
    at Object.readConfig (/Users/timothymalcham/dev/uu/node_modules/@remix-run/dev/dist/config.js:248:40)
    at processTicksAndRejections (internal/process/task_queues.js:95:5)

Is there a recommended way of resolving this?