Plugin

A plugin is a Python module that transforms the stream of directives after Beancount parses the input file. Plugins can add, modify, or remove directives and generate errors. They’re loaded with the plugin directive in the Beancount file:

plugin "beancount.plugins.unrealized"

Built-in plugins include:

• unrealized — generates entries for unrealized capital gains/losses
• auto_accounts — automatically opens accounts on first use (relaxing Beancount’s strict open requirement)
• check_commodity — validates that commodities are declared before use

Custom plugins are Python functions that receive the list of directives and options, and return a modified list plus any errors. This makes Beancount extensible without modifying its core — users write plugins for tax lot selection, custom validation rules, depreciation schedules, or domain-specific bookkeeping logic.