Build-a-Coin Cryptocurrency Creator

Sadly, Build-a-Coin is no longer maintained. It may still work for you, though!

Frequently Asked Questions

Actually nobody asked these; I wrote them up before I launched the site

What is Build-a-Coin?

Build-a-Coin is a generator of Bitcoin-derived cryptocurrencies (BDCs) or "altcoins". Given a selection of parameters, Build-a-Coin produces the source code for a new and unique coin.

Why should I trust this service?

You shouldn't. The simplest check is to download the original source your coin was templated from and compare the two. Carefully consider any differences you find.

How do I . . . with my new coin?

You'll need to set up at least two nodes, connect them with the addnode function and start mining.

Once you have some stable nodes, you'll probably want to add those nodes' IP addresses to the code as bootstrap nodes, otherwise all your users will have to addnode you before they can do anything.

Beyond those starting pointers, you'll need to look elsewhere for help. Bitcoin Talk and the Bitcoin Wiki are good resources.

One user has suggested this YouTube tutorial series for a walk-through of getting your coin up and running.

What codebase are Build-a-Coin coins based on?

Currently, all Build-a-Coin coins are derived from Litecoin 0.8.5.1.

Why Litecoin?

Litecoin is the most popular basis of manually-derived coins.

What byte do I use to get my coin's addresses to start with a specific letter/number?

Try the second chart here.

How is the genesis block mined so fast?

Build-a-Coin coins differ from bitcoin in that they do not verify the proof of work (PoW) of the genesis block. Because the genesis block is hard-coded into the client, no other proof of legitimacy is required, and skipping the genesis block PoW check allows coins to be produced on-demand without any initial mining. Mining of blocks after the genesis block is normal.

Who gets the genesis block reward?

No one. The public key that the reward of the genesis block is paid to is random and the output is therefore unspendable. Even if a public key with a known private key were inserted, all coins including bitcoin itself do not allow the reward of the genesis block to be spent.

If I enter the same values will I get the same output?

No. The genesis block of each coin is based on the time of generation as well a random nonce and coinbase output pubkey. Outside of the genesis block the code will be the same, but different genesis block means different currency.

What are alert signing pubkeys?

Bitcoin has a mechanism for warning users about important incidents like the march 2013 bitcoin fork. By default, Build-a-Coin coins have null alert pubkeys so no one may send alerts for them. If you want to be able to alert your coin's users, generate a bitcoin-compatible ECDSA keypair or keypairs and use the hex-encoded public keys.

Can I use a compressed pubkey for the alert keys?

No.