System DesignAutomationDocker

Jobsalot Claw

Real-time Auction Monitor & Sniper

Overview

Designed a real-time monitoring and automation system that tracks auction listings and executes millisecond-precision bids. Architected for persistent state, session resilience, and containerised deployment.

Architecture

Architecture: Playwright-based automation with persistent state management. Reverse-engineered Next.js React Server Component APIs for direct data access. Docker containerisation with authenticated session persistence across restarts. Event-driven monitoring loop.

Key Technical Decisions

  • 01.Reverse-engineered Next.js React Server Component (RSC) wire format for direct data access, bypassing the rendered HTML layer entirely.
  • 02.Playwright-based automation with persistent browser state — authenticated sessions survive container restarts.
  • 03.Event-driven monitoring loop with configurable polling intervals and threshold-based bid triggers.
  • 04.Docker containerisation with volume-mounted session storage, enabling stateful automation in ephemeral environments.
  • 05.Millisecond-precision bid execution timed relative to auction countdown, minimising counter-bid exposure.

Outcome

A fully containerised auction automation system capable of persistent monitoring and precision bid execution across session restarts.

Tech Stack

System DesignAutomationDocker