yashwanthvu / polkastarter-lottery

Polkastarter Lottery

polkastarter-lottery is a gem that generates a list of winners that can participate on a Polkastarter Pool. This is based on a set of criteria that aim to turn access to a Pool the most democratic and fair as possible, as well as transparent and fail-proof.

This gem is used by Polkastarter to generate lotteries.

Check this blog post to understand the full mechanic for this lottery system.

Installation

gem install polkastarter-lottery

Basic usage

balances       = { '0x111' => 3000, '0x222' => 1_000, '0x333' => 30_000 }
past_winners   = ['0x222', '0x333']
recent_winners = ['0x222']

service = LotteryService.new balances: balances,
                             recent_winners: recent_winners,
                             past_winners: past_winners,
                             blacklist: []
service.run
service.winners

Run specs

bundle install
rspec

Default settings

Price per ticket

250 POLS

Weights for each holder

*  < 250  POLS -> 0.00
*    250+ POLS -> 1.00
*  1 000+ POLS -> 1.10
*  3 000+ POLS -> 1.15
* 10 000+ POLS -> 1.20
* 30 000+ POLS -> 1.25 (cool down period is bypassed for these holders)

Cool down period

Typically, participants that won a lottery in the previous 7 days will enter a cool down period and will not be able to participate on any other Pool during those 7 days.

However 10% of them (randomly) will still be able to win and participate.

Also, holders with >= 30 000 POLS will also automatically bypass this cool down period and will be able to always participate.

Top 10 holders

Top 10 holders are always winners. They can always particiapte at any pool and also bypass the cool down period.