A streetwear store built for drop night
A drop-model storefront and a phone-first operator panel for a Hyderabad streetwear label, with UPI and cash on delivery and stock that cannot oversell.
- Client
- BLCKHUSE
- Industry
- Fashion and apparel, D2C streetwear
- Market
- India: rupees, UPI and cash on delivery
- Platform
- Next.js 14, Supabase, Razorpay
- Location
- Hyderabad, India
- Timeline
- 2026
What stood in the way
BLCKHUSE sells heavyweight tees, hoodies and caps in limited drops: a handful of pieces, one launch time, and when they are gone, they are gone. The store has to survive the one hour a drop actually happens.
- 01
Traffic arrives all at once
A drop is announced on Instagram and WhatsApp for a set time. The store has to switch from countdown to catalogue on the minute, without anyone redeploying.
- 02
The last unit gets two buyers
With a small range and shallow stock, overselling a size is the fastest way to lose a new customer's trust.
- 03
Buyers do not trust new labels yet
Shoppers who discover a brand on Reels want cash on delivery, visible policies and a person to message before they pay.
- 04
One founder runs everything
Confirming COD orders, packing, shipping and restocking all fall to one person, usually away from a laptop.
How we solved it
Five decisions shaped the build, all aimed at launch day.
- 01
One switch runs the launch
The whole storefront follows a single drop state: pre-drop, live or sold out. Before the drop, visitors see a countdown and join the waitlist. At drop time the store opens itself, synced to server time, and flipping the switch back is the rollback plan.
- 02
Stock that cannot oversell
Checkout reserves stock inside a single database transaction that re-prices every item from the database. When two buyers race for the last unit, exactly one order succeeds. Unpaid reservations release automatically after 20 minutes.
- 03
Trust built into checkout
Guest checkout with no account. UPI, cards and netbanking through Razorpay, so payment details never touch the store's servers, plus cash on delivery within set order limits, confirmed over WhatsApp.
- 04
Premium through restraint
A black-and-white design system with one expanded typeface and strong rules. The hero tee gets a 360-degree viewer customers can drag, zoom and switch colourways on.
- 05
An admin built for a phone
Today's orders, revenue, pending COD and low-stock alerts on one screen, one-tap order actions, per-size stock steppers, and a drop switch that asks for the target state to be typed before it flips.
How a drop runs
- 01Countdown and waitlist
- 02Store opens on time
- 03Stock reserved at checkout
- 04UPI, card or COD
- 05Order confirmed
- 06Shipped from the phone admin
One drop state drives the storefront, and the founder runs everything after checkout from a phone.
What we delivered
Two surfaces in one Next.js application.
Storefront
- Pre-drop countdown with an email and WhatsApp waitlist
- Shop with category filters
- Product pages with a size guide in centimetres
- 360-degree viewer with colourway swap
- Cart that survives a closed tab
- Floating WhatsApp help with a pre-filled message
Checkout and orders
- Guest checkout with Indian phone and PIN code validation
- Razorpay: UPI, cards, netbanking and wallets
- Cash on delivery with eligibility rules
- Order confirmation and shipping emails
- Order tracking with phone verification
Operator admin
- Dashboard: orders, revenue, pending COD, low stock
- Order search, filters and one-tap status changes
- Copy-address and WhatsApp-the-customer shortcuts
- Product editor with photo upload and per-size stock
- Drop control with typed confirmation
- Waitlist with one-click CSV export
What we did
- Product specification
- UI engineering
- Full-stack build
- Payments
- Admin tooling
Technology
- Next.js 14
- TypeScript
- Tailwind CSS
- Supabase Postgres
- Supabase Auth
- Supabase Storage
- pg_cron
- Razorpay
- Resend
- Zod
- Vercel
- Docker
By the numbers
- Screens: 11 storefront, 7 admin
- 18
- API endpoints for store and admin
- 18
- Atomic database functions guarding stock
- 5
- Stock hold before an unpaid order releases
- 20 min
Delivery and scope figures counted from the project itself, not client sales or traffic numbers.
Engineering that holds up
Payments you can reconcile
The Razorpay webhook is the source of truth and is safe to receive twice. Confirmation and shipping emails go out exactly once, even when events repeat.
Prices the browser cannot change
The server recomputes every price, shipping charge and COD fee from the database. A tampered cart request is rejected, not charged.
An admin locked twice
Every admin action is checked by the route itself, not only by the page in front of it. Login is rate-limited and the admin area is hidden from search engines.
Built for phones
Built to a mobile performance budget: largest content painted in under 2 seconds on 4G. Every animation switches off for visitors who prefer reduced motion, and pinch-zoom is never disabled.
A drop only works if the store opens on time and never sells the last piece twice. LoneLupus built the store and the admin so I can run launches, orders and stock from my phone.
The services behind this project
Building something like this?
Tell us what you are launching and what it has to survive. We will come back with questions, a plan and honest dates.