Skip to content
All projects
OPERATIONSCASE STUDY

Repricing Engine

Daily competitive repricer across thousands of SKUs with rule-based guardrails. Tracks margin floor, buy-box position, and competitor velocity to keep pricing honest without eroding profit.

Year
2025
Context
JS Labs
Role
Design, engineering, and operations
Stack
Next.jsSupabaseVercel CronMarketplace APIs

01 - The Challenge

Manual repricing can't keep up with competitor moves across thousands of SKUs, but naive auto-repricers create a worse problem: they race each other to the bottom and quietly destroy margin. The job isn't to always be cheapest; it's to hold buy-box position where it's profitable and walk away where it isn't.

02 - The Approach

A daily batch repricer built on explicit rules rather than a black box. Every SKU carries a margin floor computed from real costs (fees, fulfillment, FX) that no rule can cross. Above the floor, rules weigh buy-box position and competitor velocity: how fast rivals are moving, not just where they are. When the engine wants to do something unusual, it doesn't; it flags the SKU for a human instead.

03 - What I Built

A rule system with hard guardrails: margin floors computed per SKU from fees, fulfillment cost, and FX, enforced before any price is published

Buy-box and competitor tracking that feeds velocity signals (direction and speed of competitor moves) into the daily pricing decision

Daily batch runs on Vercel Cron with full pricing history in Supabase, so every price change is explainable after the fact

An exceptions queue: SKUs where rules conflict or competitors behave strangely get routed to a human instead of guessed at

04 - The Outcome

Pricing across thousands of SKUs stays competitive without anyone watching a spreadsheet, and the guardrails guarantee no price ever ships below its margin floor. The team's pricing work shrank to reviewing a short exceptions list each morning.

Daily runsMulti-SKUMargin floors

Want something like this built for you?

I take on a small number of builds like this each year: agentic systems and tooling for marketplace teams.

GET IN TOUCH