i18n-timezone-money-safety

What problem does it solve?

Prevents product correctness defects caused by mixing localized formatting with canonical storage, mishandling time zones and DST transitions, and performing unsafe money calculations that drift by cents or rounding incorrectly across currencies and regions.

Core Features & Use Cases

• Locale-safe design: Defines BCP 47 locale support, negotiation order, fallback chain, and deterministic missing-translation behavior.
• Correct time handling: Separates instants from civil dates/datetimes and specifies UTC storage plus IANA timezone retention for civil-time scenarios, including DST gap/overlap policies.
• Currency and money precision: Enforces ISO 4217 currency pairing, minor-unit or fixed-precision decimal representations, and documented rounding modes per operation to eliminate float-based monetary errors.
• Localized pluralization and collation: Mandates ICU MessageFormat usage for user-visible strings and ICU Collator-based sorting/search with Unicode NFC normalization.

Quick Start

Ask the agent to generate an i18n/timezone/money design for your change by describing the relevant user locales, the affected time fields and scheduling rules, and the money operations and currencies involved.