Codec to parse create dayjs instances from strings

dayjs-codec.mts

import * as t from 'io-ts'
import dayjs, { Dayjs } from 'dayjs'
import { pipe } from 'fp-ts/lib/function'
import { chain } from 'fp-ts/lib/Either'
import customParseFormat from 'dayjs/plugin/customParseFormat'
dayjs.extend(customParseFormat)

export const isoDate = new t.Type<Dayjs, string, unknown>(
  'isoDate',
  (u): u is Dayjs => dayjs.isDayjs(u),
  (u, c) =>
    pipe(
      t.string.validate(u, c),
      chain((d) => {
        return t.success(dayjs(d, 'YYYY-MM-DD'))
      })
    ),
  (u) => u.toISOString()
)