# John Hahn – Cal.com booking page

> Book a meeting with John Hahn on Cal.com.

Booking page: https://waferai.cal.com/john-wafer

## Event types

- [Wafer MTS Technical Interview - 3rd Round](https://waferai.cal.com/john-wafer/wafer-mts-technical-interview-3rd-round): 45 min, confirmed instantly, event type id 6511644. Details: https://waferai.cal.com/john-wafer/wafer-mts-technical-interview-3rd-round.md
- [30 min meeting](https://waferai.cal.com/john-wafer/30min): 30 min, confirmed instantly, event type id 4959356. Details: https://waferai.cal.com/john-wafer/30min.md
- [15 min meeting](https://waferai.cal.com/john-wafer/15min): 15 min, confirmed instantly, event type id 4959354. Details: https://waferai.cal.com/john-wafer/15min.md

## Check availability

```http
GET https://api.cal.com/v2/slots?eventTypeId=<event type id>&start=YYYY-MM-DD&end=YYYY-MM-DD&timeZone=<IANA time zone>
cal-api-version: 2024-09-04
```

The response is `{"data":{"YYYY-MM-DD":[{"start":"<ISO 8601 with offset>"}]}}`; no API key is needed.

## Book

Each event type's `.md` document lists its required booking fields and the `POST https://api.cal.com/v2/bookings` request (`cal-api-version: 2026-02-25`).

## More

- API docs: https://cal.com/docs/api-reference/v2/introduction