Who Is This For?
Application modernization to AWS is essential for organizations facing:
- Rising infrastructure costs from aging on-premises systems
- Compliance and security gaps in legacy environments
- Slow release cycles blocking business innovation
- Technical debt accumulating across application portfolios
- Difficulty attracting talent to maintain outdated technology stacks
If your organization is running mission-critical workloads on legacy platforms—mainframes, outdated Windows Server versions, unsupported databases, or monolithic architectures—this guide outlines how to transform them into cloud-native assets on AWS.
What You’ll Get
A structured modernization program delivers:
- Modernization Roadmap: Prioritized sequence of applications to modernize based on business value and technical feasibility
- Costed Plan: TCO analysis comparing current state vs. AWS target architecture with projected savings
- Risk Mitigation Framework: Dependency mapping, rollback strategies, and phased cutover plans
- AWS Funding Access: Qualification pathways for AMA and MAP programs
Modernization Paths: Choosing the Right Strategy
Not every application needs the same treatment. AWS defines seven migration strategies (the “7 Rs”), but four dominate modernization efforts:
Rehost (Lift and Shift)
What it is: Move applications to AWS with minimal changes.
When to use:
- Time-sensitive migrations with hard datacenter exit deadlines
- Applications with limited modernization ROI
- First phase of a multi-stage modernization journey
AWS services: EC2, EBS, AWS Migration Hub
Replatform (Lift and Reshape)
What it is: Make targeted optimizations during migration without changing core architecture.
When to use:
- Database migrations (Oracle → RDS, SQL Server → Aurora)
- Containerizing applications without refactoring code
- Adopting managed services for operational benefits
AWS services: RDS, Aurora, ElastiCache, Amazon MQ, ECS/EKS
Refactor (Re-architect)
What it is: Redesign applications to leverage cloud-native capabilities.
When to use:
- Applications with high business value and long expected lifespan
- Workloads that will benefit significantly from elasticity and scale
- Legacy monoliths constraining development velocity
AWS services: Lambda, API Gateway, DynamoDB, SQS/SNS, Step Functions
Rearchitect (Rebuild)
What it is: Rebuild from scratch using cloud-native patterns.
When to use:
- Legacy applications with unsupportable codebases
- Significant functional changes required anyway
- Greenfield opportunity with existing business logic as reference
AWS services: Full serverless stack, microservices on EKS, event-driven architectures
Assessment Programs: AMA, MAP, and OLA
AWS offers funded assessment programs to reduce modernization risk and cost. Understanding which program fits your situation is critical.
Application Modernization Assessment (AMA)
Purpose: Identify and prioritize applications for modernization with data-driven analysis.
What you provide:
- Access to discovery data (hypervisors, CMDB, application inventories)
- Application owner interviews for business context
- Source code access for static analysis (optional but recommended)
What you receive:
- Candidate application list ranked by modernization potential
- Specific modernization path per application (refactor, replatform, etc.)
- Business case with projected ROI
- Implementation roadmap
Eligibility: Organizations with 30+ applications or 100+ servers migrating to AWS.
Migration Acceleration Program (MAP)
Purpose: Fund and accelerate large-scale migrations with credits and professional services.
Benefits:
- AWS credits for migration workloads
- Access to AWS Professional Services and partners
- Prescriptive guidance and tooling
Eligibility: Enterprises with significant migration commitment and qualified spend.
Optimization and Licensing Assessment (OLA)
Purpose: Analyze current licensing and optimize for AWS deployment.
What you receive:
- License inventory and optimization recommendations
- BYOL vs. license-included cost comparisons
- Right-sizing recommendations
Deliverables: What a Modernization Assessment Produces
A comprehensive modernization assessment delivers actionable artifacts:
1. Application Inventory and Dependency Map
Complete catalog of applications, their technology stacks, and interdependencies. Identifies migration waves and highlights applications that must move together.
2. Modernization Blueprint (Per Workload)
For each candidate application:
- Current architecture analysis
- Recommended target architecture on AWS
- Specific modernization path (rehost/replatform/refactor/rearchitect)
- Effort estimate and timeline
- Risk factors and mitigations
3. AWS Service Recommendations
Target state architecture mapped to specific AWS services:
- Compute: EC2, ECS, EKS, Lambda, Fargate
- Data: RDS, Aurora, DynamoDB, Redshift, S3
- Integration: API Gateway, EventBridge, SQS, SNS
- Operations: CloudWatch, X-Ray, Systems Manager
4. TCO Model
Detailed cost comparison:
- Current on-premises costs (infrastructure, licensing, operations)
- Projected AWS costs (compute, storage, data transfer, managed services)
- 3-year and 5-year projections
- Sensitivity analysis for variable workloads
5. Risk Register
Documented risks with mitigation strategies:
- Technical risks (compatibility, performance, data migration)
- Operational risks (skills gaps, change management)
- Business risks (downtime, compliance, vendor lock-in)
- Rollback and contingency plans
Modernization Patterns
Proven patterns for transforming legacy applications:
Strangler Fig Pattern
Incrementally replace legacy functionality by routing traffic to new microservices while the legacy system continues operating. Reduces risk by enabling gradual migration and rollback capability.
Use when: Modernizing large monolithic applications that can’t be rewritten all at once.
Containerization (EKS/ECS)
Package applications into containers for consistent deployment across environments. Enables orchestration, scaling, and operational efficiency without full application rewrites.
Use when: Applications need portability, improved resource utilization, and operational consistency.
Serverless Transformation
Decompose applications into event-driven functions that scale automatically and eliminate server management overhead.
Use when: Workloads have variable demand, event-driven patterns, or when minimizing operational burden is priority.
Data Modernization
Migrate from legacy databases to AWS managed services. Includes schema conversion, data replication, and cutover strategies.
Common paths:
- Oracle → Aurora PostgreSQL or RDS
- SQL Server → Aurora MySQL or RDS SQL Server
- Mainframe data stores → DynamoDB or Redshift
Proof: Modernization Results
Large Transportation Organization
A major transportation agency modernized 30 applications through the AMA program:
Before:
- $13M hardware refresh pending
- $1.7M annual IT operations cost
- AIX, Solaris, Windows, and mainframe platforms
- 100+ critical and high CVEs in production
After:
- Hardware refresh avoided entirely
- Annual OpEx reduced to $60,000 (96% reduction)
- Fully modernized on AWS (J2EE → Serverless)
- All critical CVEs remediated
- Migration completed in 15 months
Key Success Factors
- Data-driven prioritization: Assessment identified highest-value modernization candidates
- Phased approach: Strangler Fig pattern enabled incremental migration
- AWS funding: MAP credits offset migration investment
- Expert guidance: Tidal’s assessment tools and methodology accelerated delivery
Frequently Asked Questions
Can't find the answer you're looking for? Reach out to our customer support team.
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AMA (Application Modernization Assessment) focuses on identifying which applications to modernize and how, providing a technical roadmap and business case. OLA (Optimization and Licensing Assessment) focuses specifically on software licensing optimization, helping organizations understand licensing costs and optimize for AWS deployment models.
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A typical AMA takes 1-2 weeks from kickoff to final deliverable. The timeline depends on the number of applications in scope, availability of discovery data, and scheduling of stakeholder interviews.
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We analyze your current licensing agreements and recommend the most cost-effective approach for AWS: bring-your-own-license (BYOL), license-included options, or migration to open-source alternatives. The OLA component specifically addresses licensing optimization.
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We use proven patterns like Strangler Fig for incremental migration, blue-green deployments for cutover, and database replication for data migration. Each modernization blueprint includes a rollback strategy and defines acceptable maintenance windows.
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Yes. Qualified organizations can receive a zero-cost AMA funded through AWS programs. Eligibility typically requires 30+ applications or 100+ servers planned for AWS migration. Contact us to verify your qualification status.
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Best candidates typically have high business value, active development, significant operational costs, or security/compliance gaps. The assessment uses data-driven analysis to score and rank applications by modernization potential and business impact.
Start Your Modernization Journey
Whether you’re facing a datacenter exit deadline, rising maintenance costs, or strategic pressure to accelerate innovation, application modernization to AWS delivers measurable outcomes.
The first step is understanding what you have and where to focus.
Zero cost. No obligation. Results in 1-2 weeks.
Related Resources
- Free Application Modernization Assessment — Start your zero-cost assessment today
- Cloud Migration Strategies — Overview of migration approaches and tools
- Tidal Accelerator — Discovery and assessment platform
- AWS Partnership — Our AWS competencies and programs
Deep Dives by Strategy
- Rehost Migration (Lift and Shift) — Fast path to AWS with minimal changes
- Replatform Migration — Targeted optimizations during migration
- Refactor to Serverless — Cloud-native transformation
Deep Dives by Technology
- Mainframe Modernization — Transform COBOL and legacy mainframe workloads
- Oracle to AWS — Database migration and licensing optimization
- .NET Modernization — Windows to Linux, containers, and serverless
- Java Modernization — WebSphere, WebLogic, and J2EE transformation