Buchfink is a commandline application that you can use for keeping book over your crypto trades and generate profit/loss statements and tax reports.
Under the hood, Buchfink uses algorithms and data structures from Rotki, the open source portfolio tracker. But instead of a GUI, user accounts and an encrypted database, Buchfink uses a CLI and plain text files for declarative configuration and storage.
Note: Buchfink is early alpha. Do NOT use it for tax or trading purposes. But feel free to report bugs and missing features.
If you find this useful and want to contribute to further development, consider an ETH or ERC-20 donation at coinyon.eth.
I also encourage you to try out and support Rotki. Buchfink would not be possible without it.