LEDGER № 001–008 · LEAD ENGINEER — PAYMENTS
Systems that keepmoney honest.
Selected work
FOLIO 01–04 · EVERY CLAIM HAS A NUMBER
01 · LIVE PRODUCT
Arah
Muslim companion: prayer schedule, offline Qur'an, qibla, murottal, dzikir, AI chat, widgets — public API live at api.arah.arimu.dev. Sprints 1–8 shipped to main.
READ CASE STUDY →
02 · MULTI-PLATFORM PRODUCT
Family Finance V3
Full redesign across web, Expo and native Android — crash-safe V2↔V3 switch, Ledger shell, bill-split tagihan, and background Transaction AI Audit jobs on main.
READ CASE STUDY →
03 · FINTECH BACKEND
Arus Ledger
Double-entry ledger in Go with explicit locks and a transactional outbox. Trial balance stays zero through load runs and race storms — 600 TPS sustained, p99 228 ms, zero failed writes.
READ →
04 · SECURITY
Strava Insights
Audited my own product like an attacker — IDOR chain found, closed, verified with controller security tests.
READ →The index
FOLIO 05–08Open source
PUBLIC MERGES · @arimu1 · 2026Upstream pull requests across agent runtimes, ML libraries, CLIs, and SDKs — focused on reproducible bugs, clear docs, and maintainer-friendly diffs.
Appendix — Susun
VISUAL BUILDER → AI DESIGN SPEC · 2026Drag-and-drop builder that exports a full design-spec package ready for AI coding agents. 23 components, global theming, AI layout assist, QRIS billing. React 19 · Go · PostgreSQL.
