Functional Personal Expense Tracker

Project roadmap

1. 01

   Model transactions with algebraic data types

   ~2h

   Define case classes and sealed traits for transactions, categories, and validation errors.

2. 02

   Implement add and remove operations

   ~2h

   Use Either to represent success or validation failure when adding or removing transactions.

3. 03

   Implement JSON persistence with Circe

   ~2h

   Serialize and deserialize the transaction ledger to a JSON file using Circe codecs.

4. 04

   Build a monthly summary report

   ~2h

   Aggregate transactions by category and month to produce a spending summary.

5. 05

   Write unit tests

   ~1.5h

   Test transaction operations, error cases, and JSON round-tripping.

Resources

• DocsScala Documentation