add-new-country

Create YAML tax configurations for new countries in the universal salary calculator. Use when: (1) Adding a new country to the calculator, (2) Adding a new tax year for existing country, (3) Creating variant configs (expat regimes, special tax rules), (4) Writing test vectors for configs. Triggers: "add country", "create config for", "new tax year", "add variant", "30% ruling config", etc. IMPORTANT: This skill includes automated test validation. All configs MUST pass `npm run test:configs` before completion. The skill guides you through research, implementation, test creation, validation, and debugging until all tests pass.

pascalwhoop

SKILL.md

Name

add-new-country

Description

Decidere

Decide where to live. Starting with accurate after-tax income calculations across 15+ countries.

Decidere (Latin: "to cut away options") — the act of moving from deliberation to action.

Quick Start

npm install
npm run dev

Open http://localhost:3000

Commands

npm run dev - Development server
npm run test - Run tests
npm run test:configs - Validate tax configs
npm run build - Build for production
npm run deploy - Deploy to Cloudflare

Contributing

Add new countries, tax years, or variants by creating YAML configs. The easiest way is using Claude:

With Claude (recommended):

Open this repo in Claude Code
Say: "add country [country name]" or "add [year] for [country]"
Follow the guided workflow - it handles research, config creation, tests, and validation

Manual workflow:

Create configs/<country>/<year>/base.yaml with tax rules
Add test vectors in tests/ directory
Run npm run test:configs to validate
Submit a PR

Config-only PRs get fast-tracked (~30 seconds) with automated validation.

See CLAUDE.md for detailed contribution guide.

Architecture

Config-driven: Tax rules defined in YAML files (configs/)
Pure engine: TypeScript calculation engine with no framework dependencies
Next.js UI: React frontend deployed to Cloudflare Workers

See docs/ for detailed documentation.