Need to host a demo trading competition

We want to host a trading competition for newer traders where they can trade on demo accounts. We just want to be able to access those demo accounts and to provide a leaderboard (even if the totals are just stored in a database), we can provide the front-end.

The idea is to have around 20 participants. Most will be relatively new traders. We are also not a broker, we simply have a few people learning to trade. The competition will run over the span of 30 days.