What should I do if I have a BigInt type?

error - FetchError: invalid json response body at <http://localhost:3000/api/snippet> reason: Unexpected token < in JSON at position 0
error - TypeError: Do not know how to serialize a BigInt

Out of curiousity, is this from a raw query/raw execute?

This is not an issue with Prisma but a BigInt limitation. Have a look at this workaround.