[Removal of the bonus system]

Hey everyone,

Some people might already know me from bustadice, which launched last October. A little over a week ago I also acquired bustabit from Ryan and will be running it going forwards. Due to the change in ownership it was necessary to  generate a new hash chain and hold bustabit's second provably fair seed event, which you can find here.

I also took the opportunity to release version 2 of bustabit, a complete rewrite that is more scalable and brings a number of new features and improvements.

Removal of the bonus system
Both instant busts at 0.00x and the bonus have been removed and the house edge is now a flat 1 % (read below). Although the bonus was one of bustabit's most interesting features and I am sad to see it go, our experience has shown that most players didn't consider the bonus an important part of the game. Consequently only a handful of players benefited from the bonus at the expense of all other players that ignored it.

Despite the house edge being increased in v2, the majority of players are likely better off in terms of expected value thanks to the removal of the bonus system.

Investment system
bustabit is no longer privately bankrolled. Instead, anyone can invest in the bankroll to participate in the casino's profits (and losses). To fund further development, marketing and to turn a profit, we charge a 50% commission on net profits. New investors are charged a fee of 2 %, which is shared among existing investors. This compensates them for being diluted and encourages long-term investments into a stable bankroll.

Just like in bustadice, the majority of funds are held in a multisignature cold wallet by myself, Ryan and a trusted third party.

Higher bet limits
To protect investors, the most a single player can win in one game is 1% of the bankroll, in line with the Kelly criterion. If a player were to win more than that, he will be forced to cash out. In addition, if all players in a game combined would win more than 1.5% of the bankroll, they are also forced to cash out. The bet limit has been removed entirely, allowing bets of virtually any size.

As a result, high rollers can make larger bets and overall players will be forced to cash out less often.

Deposit precredits
Don't want to wait for your deposit to be confirmed? Precredit it for a small fee and start playing immediately!

Not all deposits are eligible to be precredited and your precredited balance cannot be withdrawn, tipped or invested until your deposit confirms.

Highly optimized withdrawal system
bustabit v2 makes full use Segwit for all of its addresses. In addition, withdrawals are processed using a sophisticated custom-built coin selection algorithm which provides fantastic privacy properties.

Since it also significantly lowers our transaction costs, we are able to pass those savings on to our players. Players that would like to save even more on fees have the option of choosing a non-immediate withdrawal, which is batched with others and even cheaper.

We are confident that no other service can currently provide cheaper Bitcoin withdrawals at cost.

Friend system
You can now add other players to your friend list to see when they are online. Friends are specially highlighted, making them easy to recognize in chat and in the game's player list.

If you want to discuss something in private, you can now do so using direct messages. To prevent spam, both players must add each other before they are able to send and receive each other's private messages.

Script editor
Scripts authors can automatically generate UI for configuration, allowing scripts to be shared and used more comfortable, especially by non-technical players.

We've also sandboxed the script editor, preventing malicious scripts from accessing the rest of the browser.

[Highlights]

Ryan and I are proud to announce bustadice, a new take on classic dice.

The game is simple: For each bet the outcome is randomly chosen between 1x and 1,000,000x. It's up to you to guess a target that you think the outcome will exceed. If the bet's outcome falls short of your guess, you lose your wager. But if you guessed correctly, your wager is multiplied by your guess!

If you've played bustabit before then you'll feel right at home at bustadice, but seasoned dice players will appreciate bustadice for its simplicity and higher limits as well.

Highlights

• High limits, constrained only by the bankroll (currently Ƀ 50 max profit)
• Instant deposits available
• Native, sandboxed scripting support for custom strategies and bots
• Highly optimised wallet system for best-in-class privacy and low withdrawal fees
• Bankroll investing
• Advanced provably fair system designed to protect not only the players, but also investors
• Existing investors receive compensation from new investors when the bankroll is diluted

Bitcoin gambling has come a long way, with provable fairness towards players becoming the norm. Unfortunately investors still don't have the same kind of guarantees.

They risk casinos getting hacked or operators disappearing with their investments over night. But even at best, if neither of that happens, investors can never be certain that they aren't being undetectably cheated by someone with knowledge of future rolls. There is simply no way to know whether that incredibly lucky highroller was a legitimate player or a malicious casino operator merely pretending to be one.

Similar to how JustDice pioneered provably fair dice games, we hope that bustadice will considerably improve the situation for investors and set the standard for casino investing.

Enhanced provable fairness
bustadice builds upon conventional provably fair systems to provide additional guarantees to players, investors and the casino itself:

For players: If a dispute over fairness arises with a legacy casino, it's largely their word against yours. In bustadice, on the other hand, all bets are committed to an independent audit server in real-time and can be reviewed and verified by Ryan if need be.

For investors: Neither I nor Ryan can undetectably cheat by predicting future rolls. Assuming you trust the two not to collude, investing becomes provably fair.

In addition, the casino itself gains increased confidence that all wins are legitimate–even if the game server were to be compromised.

The way we do achieve is by introducing a third party: The auditor (Ryan). Final roll results are computed with input from all three parties: The player, the game server and the auditor. When a server seed is revealed, both the player and the auditor can verify its bets.

For a simplified high-level overview of how it works, take a look at our FAQ. Or jump right into the technical details by taking a look at our open-source verifier and reference code.

Protection against dilution
To compensate existing investors for diluting the bankroll, 2 % of every investment is distributed among all investors (including the new investor).

Multisignature cold storage
The majority of users' funds is securely held in 2-of-3 cold storage with keys split between Daniel of bustabit, Ryan and a trusted third party.

This wallet can only be accessed with the approval of at least two keyholders and ensures that users' deposits can be safely returned to them if something were to happen to one of the keyholders.

[Overview]

I am happy to announce flinch.io, a real-time Bitcoin game.

Overview

• 1 % house edge
• faucet every minute starting at 50 bits
• provably fair
• wager limit currently 30,000 bits (per round and player)
• profit limit currently 400,000 bits (per round for all players)
• single-confirmation deposits
• instant withdrawals

How does it work?
Place a bet and watch its value start to grow as soon as the game starts. You can cash out and lock in your profit whenever you like. But be careful: The game can end at any time, causing everyone that hasn't cashed out yet to lose their wager.


This is just the beginning. We have a lot planned and players can expect a steady stream of improvements and new features every two to three weeks. Next on our roadmap is multi-factor authentication and enabling players to try out the game for free.

[not]

flinch.io is an upcoming Bitcoin game that will be introduced within the next few weeks. Our provably fair system is based on the excellent work of blockage, dooglus, espringe and RHavar. It requires picking a public salt that I demonstrably cannot know yet, which I'll do in this post.

If you'd like to help me out, please quote the text after the break. Thanks!


Starting with a secret value I have generated a chain of 15,000,000 SHA256 hashes. Each element is the hash of the binary 256-bit value of the previous hash, not of its hex-encoded string representation. The hash of the final element in the chain is 90b299d1122020f324bdfd62d680d74d2bb90c0679e1503fd97a2c1a475aae18.

Every game maps to a hash in the chain: The 15,000,000th element of the chain is the hash of game #1 and the first element in the chain is the hash of game #15,000,000. To verify that a hash belongs to a game #n, simply hash it n times and compare the result with the terminating hash.

Each game's result is determined by its hash:

Code:

// GameResult calculates the corresponding crash point for a game hash and salt.
//
// Crash points have two decimal places, so a result of 1234 is interpreted as
// 12.34x. The largest possible result is 6966505673588736.
func GameResult(seed, salt []byte) uint64 {
const nBits = 46 // number of most significant bits to use

// 1. HMAC_SHA256(key=salt, message=seed
hmacHash := hmac.New(sha256.New, salt)
hmacHash.Write(seed)
seed = hmacHash.Sum(nil)

// 2. r = 46 most significant bits
seedInt := new(big.Int).SetBytes(seed)
seedInt.Rsh(seedInt, sha256.Size*8-nBits)
r := seedInt.Uint64()

// 3. X = r / 2^46
X := float64(r) / math.Pow(2, 46) // uniformly distributed in [0; 1)

// 4. X = 99 / (1-X)
X = 99 / (1 - X)

// 5. return max(trunc(X), 100)
result := uint64(X)
if result == 99 {
return 100
}
return result
}

Since JavaScript is more widespread than Go, I've also created a Node.js version of the reference function.

Before being used to calculate its game's result, each game hash is salted with the hash of Bitcoin block (#450,719) in its binary form. This block has not been mined yet, which proves that I could not have deliberately picked a hash chain that is unfavorable for players.