I am not sure why there isn't a even lightweight sentry endpoint that does

  - save post body to folders (use uuid as folder name to avoid spam)
  - dir listing, and count number of entries
  - render posted json to html, highlight stacktrace with js
  - download raw json
  - rotate, compress old entries.

That covers the most basic feature that Sentry has (one-off error reporting, with rudimentary statistics). Sure, if that's enough for you then go ahead, but for most people using Sentry that's only the tip of the iceberg.