Yuta K.

I build production-ready automations, dashboards, and API integrations — designed for reliability: schema validation, idempotency, and audit logs so systems don’t break in real operations. Credentials (Japan): Licensed Real Estate Transaction Specialist (Japan) with legal/real-estate fundamentals, and a licensed Occupational Therapist with hands-on professional experience — practical, detail-oriented, and compliance-minded by training. Recent work (selected) • Implement Connection to META Instagram Graph API with various roles: OAuth (long-lived tokens), Page↔IG linkage, publishing & scheduling, Insights, plus an App Review-ready evidence packet • Stripe Hosted Checkout Subscription Lock & Webhook Hardening: DB-less minimum-term lock via metadata, webhook stability fixes, and JSONL audit trails for every event/action • Google Apps Script + Make.com + Apify Automation: batch-based enrichment pipeline (Dispatcher/Watcher/Enricher) with low-ops runs (1 run = 3 ops), dedup keys, and append-only logs • WooCommerce / Shopify reliability work: shipping rate plugin development, webhook reachability logging, non-destructive fixes, and clear rollback paths • Finance & data pipelines: normalized data → stable JSON/CSV → charts (Google Sheets/Excel/REST), with safe fallbacks and reproducible exports What I deliver • Multi-source dashboards (Google Sheets / Excel CSV / REST APIs) where charts “never break” (guards + fallbacks) • Type-safe, schema-first validation (Zod), detailed logging, and audit exports (JSON/CSV/ZIP evidence) • API integrations: OAuth flows, webhooks (HMAC signature verification), scheduling, and monitoring • E-commerce ops automation: safe batch imports, SKU mapping, idempotency keys, notifications control, and rate-limit aware retries How I work • Synchronous, testable core logic; network calls isolated in fetchers (no async leaks) • Non-destructive changes first: reversible steps, clear scope boundaries, and evidence-based verification • Clear communication (non-native English; I confirm key points to keep us aligned) If you need a system that’s fast to operate and hard to break, I can help you ship it with logs and evidence you can trust. Communication note: I use translation tools for accuracy and keep a clear written record. I prefer chat-only by default.