CoinPortfolio

CoinPortfolio calculates the gains/losses of the current cryptocurrency portfolio.

Typically when checking the evolution of the price of bitcoin you can see how much the price increased/decreased over a period of time (e.g. day, week, year).

What if you wanted to answer the question: Would it be profitable to sell all my bitcoins now? This small library attempts to answer that question by calculating the portfolio cost, portfolio value and the percentage of gains/losses, if the portfolio were to be fully liquidated now.

The library tries to account for scenarios in which an account has multiple incoming and outgoing transactions with distinct prices using the FIFO accounting method.

This is still a work in progress.

Usage

The library uses the Coinbase API to:

• access the primary account for a given API key and secret

• iterate through all the account's transactions in order to get a snapshot of the distribution of the portfolio

• get the current price of the account's cryptocurrency

The API keys need to have the following permissions: wallet:accounts:read, wallet:transactions:read.

$ bundle exec rake console
$ api_key = "key"
$ api_secret = "secret"
$ calculator = CoinPortfolio::Calculator.new(api_key: api_key, api_secret: api_secret)
$ calculator.potential_returns
gains percentage: 25.00%
portfolio cost: €100,00
current portfolio value: €125,00

Improvements

Until now the priority has been getting a working version therefore, there are still plenty of improvements to be made:

• API client - the code that interacts with coinbase's gem is isolated in a single class which translates response hashes into domain objects. Yet the code is tied to coinbase's gem and would require some changes if there was a need to integrate with another exchange. Additionally a proper handling of API related errors hasn't been implemented.

• Multiple currencies - the code currently assumes that the user's account has a single cryptocurrency and that its transactions are all in the same native currency. This might not be true in all cases.

License

MIT (c) Mário Nzualo