Developer Shares 9 Hard-Won Engineering Lessons from Building 80+ Browser Tools

Executive Briefing

• Reveals that client-side processing relocates server infrastructure constraints to users' devices, not eliminates them
• Warns that successful demo files prove almost nothing — edge cases like 200-page PDFs expose real reliability failures
• Demonstrates how careless memory management with Base64 and Canvas objects can freeze browsers on large files
• Finds sequential processing often outperforms Promise.all on large workloads by reducing peak memory pressure
• Advises treating every third-party library as a long-term maintenance liability, not a free capability addition