Overview
Edgvance is a marketplace platform built the way large catalogues need to be built: read paths cached hard, write paths pushed onto queues, and every product decision instrumented so it can be measured instead of argued about.
Storefront tutorials stop at a product grid and a checkout button. The work starts on the other side of that. What happens when a category holds fifty thousand items, when ten thousand order confirmations need to go out, when a pricing change has to clear exactly the right cache keys and nothing else.
- Role
- Sole engineer and designer: architecture, interface, API, data model, deploy.
- Year
- 2026
- Stack
- Next.js 16.1React 19TypeScriptMongoDBRedisBullMQRazorpayPostHogTailwind CSS
Engineering
The decisions that mattered.
- 01
Redis carries the read layer
Catalogue and category reads hit Redis first, under explicit key namespacing, which keeps invalidation surgical. A price change clears that product and its parent listings. Nothing else moves.
- 02
BullMQ for everything that can wait
Order confirmations, invoice generation, inventory reconciliation and webhook retries all run as background jobs. A slow email provider cannot hold a checkout response open.
- 03
Razorpay with idempotent order handling
Payment webhooks arrive out of order and more than once. Order state transitions are written to be replay-safe, so a duplicate webhook cannot double-fulfil or double-refund.
- 04
PostHog wired to the checkout funnel
Analytics is instrumented step by step through checkout, so drop-off shows up at a specific step rather than as a general feeling that conversion is low.
Design decisions
Why it looks and behaves the way it does.
I designed this as well as built it. These are the interface calls I made and the reasoning behind each one.
Density is a feature in commerce
Shopping is one of the few places where more information per screen helps. I tightened the product grid well past what a marketing site would use, because a buyer comparing options wants to scan rather than scroll.
Price is the loudest thing on the card
Product cards carry image, title, rating, price and delivery. One of those decides the click, so price takes the strongest type weight and the rest sit back.
Checkout removes navigation entirely
Once someone enters checkout the header collapses to a logo and a step indicator. Every escape hatch is a chance to abandon, so the paths left are forward and one explicit way back.
Skeletons match the final layout
Loading states use the exact geometry of the loaded content, so cached and uncached pages feel the same and nothing shifts under your cursor when data lands.
Outcomes
What shipped.
- Handles large catalogues without per-request database fan-out
- Checkout stays responsive whatever the email and invoice providers do
- Payment flow is replay-safe against duplicate and out-of-order webhooks