Chairul AkmalSoftware Engineer

Learn the words.

A JLPT vocabulary and grammar trainer for people who gave up on Anki's setup and Duolingo's ads. Open it and study: 8,800 words, N5 through N1, scheduled by FSRS.

• Four modes over one FSRS queue: flashcard, quiz, timed exam, and 220 grammar patterns across 22 lessons.
• Every word comes with a Claude Haiku example sentence, written once and cached in Postgres. The whole deck cost about $2.55, and nothing is generated at runtime.
• Mobile-first PWA, installable, designed to an iPhone SE baseline.

• Next.js 16
• TypeScript
• Prisma
• PostgreSQL

Take the exam.

A JLPT N3 mock exam in the real paper's format: all five vocabulary question types, 35 questions, a 30-minute timer. After the session, Claude Sonnet writes a breakdown of your real level.

• Answers never leave the server during a session. The client gets shuffled choices with opaque IDs, so the correct answer never appears in network traffic.
• The wrong choices are generated offline through schema-constrained tool use. A per-word validator then rejects the circular, shared-kanji, and duplicate ones.
• The per-type accuracy radar is hand-written SVG, built from polar helpers. No chart library.
• Building it took me into Nuxt's own TypeScript config. My fix was merged upstream in July 2026: PR #35697 makes typescript.tsConfig a shared baseline for all four tsconfigs.

• Vue 3
• Nuxt 4
• TypeScript
• PostgreSQL

Run the search.

The tracker running this job search. A Rails 8 API enforces every application's status transition as a finite state machine. The Next.js board asks the server which moves are allowed instead of repeating the rules itself.

• The FSM is a plain Ruby module you can read in a few minutes, not a gem. Every transition writes the status and its timeline entry in one database transaction. Optimistic locking turns a concurrent edit into a 409 instead of a silent overwrite.
• Ghost prediction flags applications that have been silent longer than your own p90 reply time. It is rebuilt from the audit trail with a window function, so it needed no new column and no new table.
• A daily follow-up digest goes out at 08:15 JST. It skips weekends, Japanese national holidays, New Year, Golden Week and Obon, and moves those reminders to the next business day instead of dropping them.
• Bilingual in English and Japanese. CI checks that the two translation catalogs stay in sync, because a missing key still typechecks and builds without errors.

• Rails 8
• Next.js 16
• TypeScript
• Playwright