denaro

denaro, 'money' in italian, is a cryptocurrency written in Python.
Maximum supply is 30.062.005.
Maximum decimal digits count is 6.
Blocks are generated every ~3 minutes, with a size limit of 2MB per block.
Assuming an average transaction to be composed by 5 inputs and 2 outputs, that are 250 bytes, a block can contain ~8300 transactions, which means ~40 transactions per second.

Setup with Docker

• Build the base image with make build
• $ docker-compose up -d

Installation

Before installing denaro, you need to create the postgresql database.
You can find the schema in schema.sql.
You have to set environmental variables for database access:

• DENARO_DATABASE_USER, default to denaro.
• DENARO_DATABASE_PASSWORD, default to an empty string.
• DENARO_DATABASE_NAME, default to denaro.
• DENARO_DATABASE_HOST, default to 127.0.0.1.

# install postgresql
createdb denaro

Then install denaro.

git clone https://github.com/denaro-coin/denaro
cd denaro
psql -d denaro -f schema.sql
pip3 install -r requirements.txt
uvicorn denaro.node.main:app --port 3006

Node should now sync the blockchain and start working

Mining

denaro uses a PoW system.

Block hash algorithm is sha256.
The block sha256 hash must start with the last difficulty hex characters of the previously mined block.
difficulty can also have decimal digits, that will restrict the difficulty + 1th character of the derived sha to have a limited set of values.

from math import ceil

difficulty = 6.3
decimal = difficulty % 1

charset = '0123456789abcdef'
count = ceil(16 * (1 - decimal))
allowed_characters = charset[:count]

Address must be present in the string in order to ensure block property.

Blocks have a block reward that will half itself til it reaches 0.
There will be 150000 blocks with reward 100, and so on til 0.390625, which will last 458732 blocks.
The last block with a reward will be the 458733th, with a reward of 0.3125.
Subsequent blocks won't have a block reward.
Reward will be added the fees of the transactions included in the block.
A transaction may also have no fees at all.