Add a tax year

Use this guide when a supported calculator needs a new official tax year, parameter period or date boundary.

Before you start

• Read Rules and parameters.
• Read Calculators.
• Check the current supported tax years in Jurisdictions and tax years.

Rule packages own tax-year parameter tables and rule-pack composition. @taxkit/core owns the shared TaxYear brand and australianTaxYearInterval. Rule packages narrow that brand to supported literals such as AuPayTaxYear or AuAnnualTaxYear.

Proposal

Document:

• the official source for each table or rate
• the effective start and end dates
• the calculator IDs and jurisdictions the year supports
• the parameter service that owns each table
• expected differences from the previous year
• release impact for API metadata and SDK descriptors

Implementation

Add tax-year data as schema-validated parameters. Compose it into the owning rule pack and calculator catalogue only after golden tests prove the year.

official source
  -> parameter table schema
  -> parameter descriptor with effective period
  -> rule-pack layer
  -> calculator catalogue entry
  -> API and SDK metadata

Do not default missing request context to a jurisdiction or tax year in HTTP, SDK or calculator service code. Missing context must be absent, schema-owned or rejected with a tagged expected error.

Tests

Your evidence should include:

• parameter schema validation
• source reference validation
• effective-date overlap checks
• golden tests for the new tax year
• date-boundary tests around year start and end
• API compatibility tests proving metadata lists the year
• SDK compatibility tests proving unsupported tax-year literals still fail type tests

Pull request evidence

Include source citations, changed parameter periods, commands and release impact in PR evidence checklist.

Read this page as Markdown