The Problem
A UK-based payments startup was experiencing recurrent production outages every 3–4 days, averaging 8 hours of cumulative downtime per month. Their checkout flow would silently fail during high-traffic periods, causing transaction loss and customer churn. The engineering team had no visibility into the root cause and every hotfix introduced new regressions.
The Challenge
The application was running on an untuned single VPS with no queue monitoring, no error tracking, and a heavily patched legacy codebase that had evolved without any architectural oversight. Queue workers were silently dying due to memory exhaustion, causing jobs to pile up and time out with no alerts. Database connections were being exhausted during peak checkout periods due to unbounded connection pools.
Our Solution
We conducted a 48-hour deep-dive audit using Laravel Telescope and Sentry telemetry. Key fixes included:
• Implemented Laravel Horizon for queue management with real-time visibility
• Set memory limits and graceful restart policies on all queue workers
• Replaced raw DB::connection() calls with Eloquent's connection pooling
• Added Redis-backed rate limiting to the checkout endpoints
• Deployed health check monitors with 60-second PagerDuty alerting
• Migrated from shared Redis to dedicated Redis with persistence enabled
• Implemented Laravel Horizon for queue management with real-time visibility
• Set memory limits and graceful restart policies on all queue workers
• Replaced raw DB::connection() calls with Eloquent's connection pooling
• Added Redis-backed rate limiting to the checkout endpoints
• Deployed health check monitors with 60-second PagerDuty alerting
• Migrated from shared Redis to dedicated Redis with persistence enabled
The Result
Within 72 hours of deployment, queue failures dropped to zero. Over the following 30-day period, the application achieved 99.97% uptime with zero critical incidents. Transaction success rates improved from 91.4% to 99.3%, and the team now has full observability into every worker, job, and queue depth in real-time.