Legacy App Modernization Services

Our structured legacy application modernization process balances thorough assessment, strategic planning, and incremental delivery to transform outdated systems while maintaining business operations.

Assessment & Discovery (2-4 weeks)

We begin with comprehensive analysis of your legacy application understanding current architecture, identifying technical debt, documenting dependencies, and uncovering modernization opportunities and risks.

Key Activities:

• Current state analysis of application architecture, codebase, and infrastructure
• Technical debt assessment identifying outdated technologies, security vulnerabilities, and performance issues
• Dependency mapping documenting integrations, databases, and external systems
• Business logic documentation capturing critical workflows and rules
• Stakeholder interviews understanding pain points and modernization goals
• Risk assessment identifying potential migration challenges and mitigation strategies
• Technology landscape review evaluating modern alternatives and recommendations

Deliverable: Comprehensive assessment report, technical debt inventory, and initial modernization recommendations

Strategy & Roadmap Development (2-3 weeks)

Our team develops a detailed modernization strategy prioritizing improvements, defining target architecture, and creating a phased roadmap that balances quick wins with long-term transformation goals.

Key Activities:

• Target architecture design (microservices, cloud-native, serverless, etc.)
• Modernization approach selection (re-host, re-platform, re-architect, re-code, refactor, or hybrid)
• Phased roadmap creation breaking modernization into manageable increments
• Quick wins identification for early value delivery
• Risk mitigation planning for critical dependencies and complex migrations
• Cost-benefit analysis showing ROI for modernization investment
• Team composition and resource planning

Deliverable: Modernization strategy document, target architecture design, phased roadmap with timelines and investment

Incremental Modernization (3-12 months)

Phased transformation of legacy application following the roadmap, delivering working increments every two weeks while maintaining business continuity and minimizing risk through gradual migration.

Key Activities:

• Infrastructure modernization (cloud migration, containerization, CI/CD setup)
• Code migration and refactoring using AI-assisted tools
• API development replacing outdated interfaces with modern REST or GraphQL
• Database migration and optimization
• Microservices extraction from monolithic architecture
• Integration with modern platforms and services
• Continuous testing ensuring functionality preservation
• Parallel running of legacy and modernized components during transition

Deliverable: Incrementally modernized application with improved performance, security, and maintainability

Testing & Validation (Throughout + 2-4 weeks final)

Comprehensive testing throughout modernization process with intensive validation phase before full production cutover ensuring all functionality works correctly and performance meets requirements.

Key Activities:

• Automated regression testing for every code change
• Performance testing validating speed and scalability improvements
• Security testing and vulnerability assessment
• User acceptance testing with business stakeholders
• Load testing simulating production traffic patterns
• Data integrity validation ensuring no data loss or corruption
• Disaster recovery testing
• Production readiness review

Deliverable: Test reports, performance benchmarks, validated modernized application ready for production

Production Migration & Cutover (1-2 weeks)

Carefully orchestrated transition from legacy to modernized system using zero-downtime deployment strategies, with rollback procedures ready if unexpected issues arise.

Key Activities:

• Final data migration with validation
• Blue-green deployment or canary release for gradual traffic migration
• Production monitoring and performance tracking
• User training and support during transition
• Rollback procedures on standby
• Issue triage and rapid response for any problems
• Post-migration validation and smoke testing

Deliverable: Fully modernized application running in production with legacy system retired

Optimization & Continuous Improvement (Ongoing)

Post-modernization support focusing on optimization, monitoring, and continuous improvement based on production usage patterns and evolving business requirements.

Key Activities:

• Performance monitoring and optimization
• Security updates and vulnerability patching
• Feature enhancements based on user feedback
• Technical debt reduction continuing modernization journey
• Cost optimization for cloud resources
• Scalability improvements as usage grows
• Knowledge transfer and team enablement

Deliverable: Continuously optimized modern application with ongoing support and improvements

Legacy app modernization costs vary significantly based on application complexity, codebase size, modernization scope, technology stack differences, and chosen modernization approach (re-host vs re-architect vs re-code). Projects typically range from $100,000 for straightforward re-platforming to $1,000,000+ for complete re-architecture of complex enterprise systems. Most organizations invest 20-40% of their legacy system's original development cost in comprehensive modernization.

At Scrums.com, we provide flexible, usage-based pricing for legacy application modernization through our Software Engineering Orchestration Platform (SEOP). All projects begin with a platform subscription tier, then you add modernization team members (architects, developers, QA engineers) based on hours worked and resources needed—no hidden fees, no vendor lock-in. As a software development company with 13 years of experience and AI-assisted modernization tools, we deliver 40-60% cost savings compared to traditional consulting firms while providing complete transparency through real-time SEOP dashboards. Factors that often influence the cost of legacy app modernization include...

Application Size & Complexity

Small applications (under 50,000 lines of code, limited integrations) cost less to modernize than large enterprise systems (500,000+ lines, complex business logic, extensive integrations). Application complexity—including number of features, data models, user roles, workflows, and edge cases—directly impacts assessment time, migration effort, and testing requirements.

Modernization Approach & Scope

Re-hosting (lift-and-shift to cloud) is least expensive but delivers limited benefits. Re-platforming adds moderate cost with better optimization. Re-architecting (microservices, cloud-native) or re-coding (complete rewrite in modern languages) are most expensive but deliver maximum long-term value. Hybrid approaches balance cost and benefit by applying different strategies to different application components.

Technology Stack Migration

Migrating between similar technology stacks (PHP to Node.js, MySQL to PostgreSQL) costs less than radical changes (COBOL to Java microservices, mainframe to cloud-native). Greater technology distance increases learning curve, architectural differences, and migration complexity. AI-assisted code migration tools significantly reduce manual rewriting effort and accelerate transitions.

Testing & Quality Assurance Requirements

Comprehensive testing ensuring zero functional regression requires significant effort proportional to application complexity. Mission-critical systems need extensive automated testing, performance validation, security audits, and user acceptance testing. Higher risk tolerance reduces testing costs but increases production incident risk. Balance thorough validation with project budget and risk appetite.

Integration Complexity & Dependencies

Applications with numerous integrations (databases, APIs, third-party services, internal systems) require more planning, testing, and migration coordination. Each integration point needs assessment, potential modernization, testing, and validation. Complex dependency webs where legacy system interacts with many other systems increase project scope and coordination overhead.

Ongoing Modernization & Optimization

Post-modernization costs include continued technical debt reduction, performance optimization, security updates, cloud cost optimization, and feature enhancements. Budget 15-20% of initial modernization investment annually for continuous improvement and keeping systems current. Modernization is a journey, not a destination—technology continues evolving, requiring ongoing investment.