Fairlotto V2: Provably Fair STEEM Blockchain Based Lottery - All New Front-End + Features
Introducing the all new V2 of the Fairlotto STEEM Lottery. New front-end and added features
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New features
All new website https://www.fairlotto.eu
Steemconnect integration
Subscription model
New weekly lottery and increased ticket prices
What is @fairlotto?
Fairlotto offers a way for Steemians to spend some of their hard earned SBD's and have some fun in a lottery that is provably fair.
Goal
The goal for Fairlotto is to offer a well respected lottery on the STEEM Blockchain which grows as the STEEM community is growing. Becoming the #1 lottery on STEEM and eventually offering a monthly lottery with huge prize pools.
How to play
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Steemconnect
Participating is very easy with the new front-end, go over to https://www.fairlotto.eu and decide in which lottery you want to partake, Steemconnect will take care of the rest.
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Lotteries
Fairlotto currently offers 3 different lotteries: hourly, daily and weekly. Each with their separate prize pool and deadlines. Direct ticket sale is possible to enter 1 lottery, you can buy as many tickets as you want. However, newly added is the subscribe function which offers the option to subscribe for a lottery. When a new lottery starts 1 ticket will be automatically purchased automatically every new lottery until your balance is depleted.
Bonus
The prize pool is made up of all the ticket sales. However additional bonus funds can be added during promotional runs. As an offer to the small minnows on STEEM there is the intent to always offer a bonus for the hourly lottery.
Supported commands in memo
Direct purchases are also available. Send the SBD amount with one of the following memos to @fairlotto.
Command Action
hourly buy SBD/ticket_price amount of ticket for the next draw
daily buy SBD/ticket_price amount of ticket for the next draw
weekly buy SBD/ticket_price amount of ticket for the next draw
subscribe-hourly Add SBD to hourly lottery balance and buy 1 ticket
subscribe-daily Add SBD to daily lottery balance and buy 1 ticket
subscribe-weekly Add SBD to weekly lottery balance and buy 1 ticket
Lottery statistics
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The website shows several tables with all the data relevant to the current lotteries. This includes data like the current prize pool, how many players have entered but also all the transactions. And information relevant to verifying the authenticity of the draws.
Payout and fee structure link
The payout structure is based on the amount of tickets participating in the draw. There need to be at least 2 different users participating in the draw for it to be valid.
Between 2 and 5 tickets:
#1 95% Prize pool + optional bonus
5% fee
Between 5 and 10 tickets:
#1 75% Prize pool + optional bonus
#2 20% Prize pool + optional bonus
5% fee
More than 10 tickets:
#1 50% Prize pool + optional bonus
#2 10% Prize pool + optional bonus
5% of tickets receive 20% Prize pool + optional bonus
10% of tickets receive 10% Prize pool + optional bonus
10% of tickets receive 5% Prize pool + optional bonus
5% fee
Provably fair link
The most important thing about a lottery is that it is fair. For this reason this lotto is made provably fair. This means that users will be able to verify the outcome. The server hash is obtained by hashing the server seed, which is a secret used to perform the calculations. The sha256 hash of the server seed is unique and can be used to verify after the drawing the server seed was not changed. As the server seed is revealed after the drawing.
Also used in the calculation is the transaction_id of the last person who bought a ticket. This is a random string which cannot influenced. This prevents calculating in advance which ticket will win and buying the ticket with a separate bot.
To calculate which tickets will win the server hash, transaction id, a colon and a roll number(starting from 0) are string together. This string is hashed with a hmac-sha512() function that gives a 128 character hex string. From this string the first 5 characters are taken and converted to a decimal number. This number will be between 0 and 1048575. If this number corresponds to a ticket number there is a winner, if not the roll number will increase by 1. This process repeats itself until all winners are decided. Each ticket can only win once. Below is a rough outline of the process.
A simple tool to verify the outcome of a draw will be released shortly.
Roadmap: what is on the horizon?
Detailed page for all prior lottery draws and and verification tools.
User authentication with Steemconnect for active control over subscriptions and overview into user statistics.
A monthly mega lottery when there is a big enough user base.
Jackpot
STEEM Blockchain
This project runs on the STEEM Blockchain as that user verification and draw validation are done by using data from the blocks that make up STEEM.