Legacy applications are costing B2B SaaS companies 15-30% of their engineering budgets. The question isn't whether to address technical debt—it's when and how.
The Cost of Legacy Applications
Hidden Costs: Technical debt (15-25% of monthly engineering budget), cloud waste (10-20% of infrastructure costs), security risks (potential breaches costing millions), developer productivity (30-40% slower feature development), and opportunity cost (can't implement new features or scale).
Total Impact: Legacy apps typically cost $180K-$360K annually for companies with $50K monthly engineering budgets.
Rebuild vs. Refactor: Decision Framework
When to Rebuild
Rebuild when technical debt >30% of monthly costs, security vulnerabilities can't be patched, architecture prevents scaling, tech stack is obsolete, data migration is feasible, or timeline allows for 60-90 day rebuild.
When to Refactor
Refactor when technical debt <20% of monthly costs, architecture is sound but needs optimization, security can be improved with patches, tech stack is modern but code quality is poor, or timeline is critical.
ROI of Professional Rebuilds
Real Example: Legacy app monthly cost $50,000, rebuild cost $85,000 (Growth tier), new monthly cost $15,000 (70% reduction), monthly savings $35,000, payback period 2.1 months, 5-year ROI 1,733%.
Rebuild Process
Phase 1: Assessment - Technical audit, architecture review, cost analysis, risk assessment.
Phase 2: Blueprint - Technical specifications, infrastructure design, security plan, migration strategy.
Phase 3: Development - Foundation tier 60 days, Growth tier 90 days, Scale tier 120 days.
Phase 4: Migration - Data migration, testing, deployment, monitoring.
Get Started: Start with a free technical audit at WebEvo.ai to identify technical debt, then get a complete rebuild blueprint at Appspark.ai for $1,500.