Salary slip kata

Salary Slip Kata is a programming exercise designed to help developers practice Test-Driven Development (TDD) and clean code principles. It focuses on building a salary slip generator for UK companies that calculates monthly earnings, national insurance contributions, and income tax based on progressive tax bands.

Key Features

• Progressive Tax Calculations — Implements UK tax rules including basic, higher, and additional rate bands with varying percentages.
• National Insurance Contributions — Calculates contributions with different rates for income thresholds.
• Tax-Free Allowance Reduction — Handles the decrease in personal allowance for high earners above £100,000.
• Fixed Interface — Uses a predefined SalarySlipGenerator class interface to enforce design constraints.
• Iterative Development — Builds functionality step-by-step across six iterations, each adding complexity.
• Test-Driven Approach — Encourages writing tests first with clear acceptance criteria and expected outputs.

Philosophy

The kata emphasizes incremental development through small, verifiable steps, teaching developers to manage complexity while maintaining clean, testable code.