Solo product39 days, idea → production

Onescle — The e-commerce operating system for Bangladesh

A multi-tenant SaaS that gives every merchant a storefront, an owner dashboard, courier booking, local payments, fraud protection, a POS and mobile apps — in Bangla and English.

Visit live site Seller app on Google Play

39days to production

730commits

1,148API routes

178data models

757test files

7apps shipped

My role

Founder-engineer — system design, backend, web, mobile, DevOps, marketing

The problem

Bangladeshi merchants juggle six disconnected tools and lose money on fake cash-on-delivery orders that also poison their Meta ad targeting.

Stack

NestJS 11FastifyPrisma 7PostgreSQL 17RedisRabbitMQNext.js 16React 19FlutterCloudflare R2DokployGemini

Storefront theme templates were contributed by a teammate.

What I built

Postgres row-level security per transaction on top of app-level tenant scoping — 65 RLS policies across 178 models.
Load-tested at 10,000 tenants / 554k products: 248–308 req/s at p95 ≈ 150 ms, zero errors — after finding and fixing an index that made every tenant pay for every other tenant.
RabbitMQ with outbox, retries, dead-letter queue and idempotency keys, in a separate worker process.
Fraud Shield: scores orders and holds the Meta CAPI Purchase event until a COD order proves real, so ad spend never optimises for fraudsters.
7 payment providers (bKash, Nagad, SSLCommerz, Stripe, COD…) and 5 couriers (Steadfast, Pathao, RedX, Carrybee) behind single interfaces with reconciliation jobs.
One OpenAPI contract generates typed clients for 3 Next.js apps and 2 Flutter apps.
Offline-capable Flutter desktop POS with receipt printing, cash drawer via FFI and a CI-built Windows installer.
Custom domains with wildcard TLS and one-click Cloudflare DNS setup; Gemini-powered product drafts from a photo.

39 days, phase by phase

Reconstructed from 730 commits between Aug 22 and Sep 29, 2026.

1
Day 1–2
System design
Monorepo, 59-section architecture doc, tenancy model, outbox + DLQ, first order and inventory modules.
2
Day 3–10
Commerce core
Orders, inventory reservations, payments, shipping, media — storefront and both dashboards scaffolded.
3
Day 11–17
Platform & launch infra
Admin platform, auth + 2FA, custom domains, RabbitMQ, brand identity — production on Dokploy by day 17.
4
Day 18–24
Storefront engine
Theme gallery, page-builder canvas, code registry and merchant onboarding.
5
Day 25–31
Growth & trust
Meta Pixel + Conversions API, Fraud Shield, SEO, i18n and the marketing site.
6
Day 32–39
Apps & hardening
Flutter seller app and desktop POS, PWA, security review — live on Google Play.

Architecture

Follow a request from top to bottom: every visitor enters through Cloudflare (custom domains, SSL, security), reaches the apps, then one API and a background worker.