About kumo studio

kumo studio is a one-person Shopify app shop. I'm fukkun, based in Japan, and I build small focused apps for Shopify merchants.

What we build

SimpleStock — an inventory app for Shopify stores that need low stock alerts, reorder suggestions, and dead stock detection without paying for POS Pro. Free plan covers 30 SKUs, paid tiers start at $14.99/month.

chouhyo (スマート帳票) — a Japanese invoicing app that auto-generates receipts, delivery notes, and invoices for Shopify orders. Built for Japan-specific requirements: 適格請求書 (qualified invoice), 電子帳簿保存法 (e-bookkeeping law), and 軽減税率 (reduced tax rate) compliance.

How I work

Solo. Build-in-public oriented. I write the code, run support, talk to merchants directly. There's no sales team — if you email support@kumostudio.dev, it lands in my inbox.

This blog is where I write up what I learn shipping these apps — the technical details, the merchant problems I run into, the trade-offs I make. Most posts are problem-solving guides, not product pitches.

Get in touch