UFC Rankings API: official boards, point-in-time since 2013

$ curl "https://api.ufcalendar.com/v1/rankings/ufc?date=2016-11-14" \
    -H "Authorization: Bearer $UFCAL_KEY"

{
  "data": {
    "org": "ufc",
    "board": "official",
    "snapshot_date": "2016-11-07",
    "divisions": [
      {
        "division": "lightweight",
        "entries": [
          { "rank": 0, "is_champion": true,
            "name": "Eddie Alvarez", "fighter_slug": "eddie-alvarez" },
          { "rank": 1, "name": "Khabib Nurmagomedov",
            "fighter_slug": "khabib-nurmagomedov" },
          ...

import requests

API = "https://api.ufcalendar.com/v1"
H = {"Authorization": f"Bearer {UFCAL_KEY}"}

# What was the lightweight board the week of UFC 205?
board = requests.get(f"{API}/rankings/ufc", params={"date": "2016-11-14"}, headers=H).json()["data"]
lw = next(d for d in board["divisions"] if d["division"] == "lightweight")
for e in lw["entries"][:6]:
    print("C " if e["rank"] == 0 else f"#{e['rank']:<2}", e["name"])

# One fighter's full ranking history (every snapshot he appeared on)
hist = requests.get(f"{API}/fighters/khabib-nurmagomedov/rankings", headers=H).json()["data"]
print(len(hist), "ranking rows, first:", hist[0]["snapshot_date"])

const API = "https://api.ufcalendar.com/v1";
const headers = { Authorization: `Bearer ${process.env.UFCAL_KEY}` };

// Current official board, then the same board on any past date
const now = await fetch(`${API}/rankings/ufc`, { headers }).then((r) => r.json());
const then = await fetch(`${API}/rankings/ufc?date=2016-11-14`, { headers }).then((r) => r.json());

const champ = (b, div) =>
  b.data.divisions.find((d) => d.division === div)?.entries.find((e) => e.rank === 0)?.name;
console.log("LW champion now:", champ(now, "lightweight"), "| Nov 2016:", champ(then, "lightweight"));