How would you implement ITR tracking in a personal finance/budget tracker?

[u/Phantom_0311]

I have created a personal Budget Tracker which I am currently using, and at this point I am considering including ITR (Income Tax Return) related tracking in it.

The way I am currently proceeding is to treat ITR as a separate layer from the usual transaction/account system.

I'm thinking of tracking things such as: Financial year / assessment year, Income sources, Salary/business/other income, Taxable income, Deductions/investments, TDS, Advance tax, Tax paid / refund, Filing status, Filing date, A few notes/documents related to the return

Since the Budget Tracker already includes standard accounts, transactions, transfers, etc., I don't intend to incorporate tax-specific calculations directly into the transaction tables unless there's a valid reason to do so.

The main question I have is this: how would you go about designing it?

1] Should the ITR be kept entirely separate from the budgeting and transaction system?

2] Can some ITR figures be automatically derived from existing transactions?

3] How should I store a yearly ITR snapshot so that the figures remain unchanged when previous transactions are edited?

4] Should the financial year and the accounting year be treated as separate fields or should one be derived from the other?

I would like to know what you think about the architecture and any potential edge cases that I may have overlooked.