SwiftBidder

Ongoing · Full-Stack Application · 2026-05-26

A real-time auction platform where bids update live across every connected browser.

Tech stack: Laravel, PHP, React, InertiaJS, TailwindCSS, PostgreSQL, Pusher, Docker

SwiftBidder is a real-time auction platform built with Laravel 12 and React over Inertia. Admins list items with a start and end window; bidders browse what's open and place bids that appear instantly in every other connected browser, without a refresh.

Problem

An auction is only fair if everyone is looking at the same number at the same time. The moment one bidder's screen is stale, they're bidding against a price that no longer exists. A page that only updates on reload turns a live auction into a guessing game — so the interesting problem here wasn't the CRUD around auctions, it was keeping every viewer honest about the current price and making the bidding rules hard to get around.

Approach

Each auction gets its own broadcast channel. When a bid is accepted the server emits a BidPlaced event over Pusher, and every client watching that auction updates its current price and bid history in place. The bidder who placed it doesn't get their own event echoed back — the UI already reflects it.

Auction state is derived rather than stored. Instead of a scheduled job flipping rows between pending, active and closed, the status is computed from the auction's own start and end times whenever it's read. That removes a whole class of bug: there's no window where the database disagrees with the clock, and no cron job to keep alive for the app to be correct.

Key features

Live bid updates broadcast over WebSockets — no polling, no manual refresh
Bid history showing recent bids and the current winner, updating in real time
Server-side bid rules: a bid must beat the current price, and you can't outbid yourself
Auction lifecycle (pending → active → closed) derived from time windows
Role-based access separating auction administration from bidding
Multi-image uploads served from S3-compatible object storage
Registration with emailed OTP verification
Light and dark themes across the whole interface

Tech stack & role

I built this solo, end to end. Laravel 12 and PostgreSQL on the backend, React with Inertia and TailwindCSS on the front, Pusher for the real-time layer, and Cloudflare R2 for uploaded images. It ships as a multi-stage Docker image — Vite builds the assets, then nginx and PHP-FPM serve them — deployed on Render behind a managed Postgres instance.

Outcome & what I learned

The live demo runs on seeded data with public demo accounts, so anyone can sign in as an admin or as one of several bidders and watch prices move between two browser windows.

The lesson that stuck was about derived state. My first instinct was a scheduled command marking auctions active or closed on a timer, which meant the app was only correct as often as the scheduler ran — and quietly wrong in between. Computing the status from the timestamps instead made a moving part disappear entirely. Deploying it taught the same lesson from the other direction: uploads written to a container's own disk vanish on every deploy, which is only obvious once it happens to you.