# 15 min at the ACE booth: for builders with Panagiotis Tsafaridis

> Show us one question your new developers always ask. We run it with ACE on our own repo. Wednesday 11 Nov is online only (Google Meet); Thursday and Friday you can also meet us in person in Lisbon.

- Host: Panagiotis Tsafaridis
- Duration: 15 min
- Location: Google Meet, In person in Lisbon (Thu 12 / Fri 13 Nov only), place confirmed by mail
- Host time zone: Europe/Lisbon
- Confirmation: Bookings are confirmed instantly.
- Booking page: https://cal.com/ce-dot-net/websummit
- Event type id: 7861345

## Check availability

```http
GET https://api.cal.com/v2/slots?eventTypeId=7861345&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

```http
POST https://api.cal.com/v2/bookings
cal-api-version: 2026-02-25
Content-Type: application/json

{
  "eventTypeId": 7861345,
  "start": "<UTC ISO 8601 start from the slots response>",
  "attendee": {
    "name": "…",
    "email": "…",
    "timeZone": "<IANA time zone>"
  },
  "guests": [
    "guest@example.com"
  ],
  "bookingFieldsResponses": {
    "company": "…",
    "team-size": "…",
    "role": "…",
    "note": "…",
    "notes": "…"
  }
}
```

- Required fields: `name` (Your name), `email` (Email address), `company` (Company), `team-size` (Engineering team size)
- Optional fields: `role` (Role), `note` (One question your new devs ask), `notes` (Additional notes), `guests` (Add guests)
- `name` and `email` go in `attendee` and `guests` is a list of emails; every other field goes in `bookingFieldsResponses` under its name.
- `location` is optional; without it the booking uses the event’s first location.