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TypeScript-first Japanese postal code (郵便番号) lookup with address autofill and a Vue 3 composable. Zero dependencies, fully typed.

1 starsTypeScript

Nihonpost – I parsed Japan Post's KEN_ALL.CSV so you don't have to

Name: Nihonpost – I parsed Japan Post's KEN_ALL.CSV so you don't have to
Availability: InStock
Author: kitsunechaos

by kitsunechaos·Jul 13, 2026·3 points·0 comments

AI Analysis

●●SolidSolve My ProblemCozy

Vue composable handling full-width input and offline Japanese address lookup.

Strengths

•Handles full-width character normalization and 〒 symbols automatically out of the box.
•Chunks 124k codes by prefix for lazy loading, keeping initial bundle size minimal.
•CI-driven monthly data updates ensure address database stays current without manual patches.

Weaknesses

•Vue 3 composable focus excludes React or Svelte users without a rewrite.
•Solves a specific regional problem that limits the potential user base significantly.