What are application modernization best practices?
TL;DR
- Organizations that modernize successfully start by identifying the business outcomes that are constrained by legacy technology.
- Then, they prioritize investments based on value, risk, cost, and speed to impact.
- The most successful organizations treat modernization as an ongoing capability.
- They continuously evaluate their application landscape, invest in reusable platforms and delivery accelerators, modernize incrementally, establish governance that enables speed without risk, and evolve their operating models to support AI, innovation, resilience, and future business growth.
JUMP TO:
How do you align application modernization with business goals?
Application modernization should never begin with architecture diagrams or platform decisions. The most successful organizations start with business intent and align with business outcomes. That could mean:
- Revenue growth: Launching new products, services, or experiences faster
- Customer experience innovation: Removing friction from digital experiences
- Operational resilience: Reducing downtime, outages, and business continuity risk
- Risk reduction: Addressing security, compliance, and regulatory concerns
- AI enablement: Creating trusted data and modern platforms for AI
- Workforce productivity: Helping employees spend less time navigating bottlenecks and workarounds
- Talent retention: Reducing reliance on aging technologies and scarce skills
- M&A readiness: Making systems easier to integrate during acquisitions
- Ecosystem integration: Connecting with partners, suppliers, marketplaces, and third-party services
- Time-to-market velocity: Reducing the time required to deliver business change
The wrong question: "Which applications should we modernize?"
The right question: "Which business outcomes are being constrained by legacy technology?"
Examples of application modernization for streaming, sports, and entertainment industry
Modernization outcomes are extremely tangible and make both a quick and lasting impact for brands.
Here are six examples of high-value app modernization outcomes for streaming and entertainment brands:
- Content delivery: Deliver live sports and tentpole premieres without buffering spikes, even during record-breaking concurrent viewership
- Subscriber growth: Bring new streaming products and seasonal/regional offerings to market faster while reducing operational overhead
- Personalization: Identify churn risk earlier and trigger targeted retention offers before subscribers disengage
- Ad-supported experiences: Increase advertising yield through audience-based targeting and dynamic, ambient ad decisioning
- Global expansion: Adapt quickly to market-specific regulations, rights management requirements, and customer preferences
- AI readiness: Automate content tagging, metadata enrichment, and media supply chain workflows at scale
Application portfolio modernization checklist
Here’s a high-level checklist for assessing, documenting, and prioritizing application modernization that earns its spend:
- Step 1: Create a complete application invenory
- Step 2: Evaluate business value, technical health, and AI readiness
- Step 3: Assess security, resilience, and compliance exposure
- Step 4: Identify technical debt, cloud spend, and support costs
- Step 5: Map application and data dependencies
- Step 6: Rationalize redundant and low-value applications
- Step 7: Build a value vs. effort prioritization framework
- Step 8: Focus on quick wins, strategic platforms, and business-critical capabilities
Step 1: Create a complete application inventory
The first step in assessing and prioritizing an app portfolio is creating a comprehensive list of what you have and how it’s used:
- Business purpose
- Users
- Technical architecture
- Integrations
- Data dependencies
- Support costs
- Security posture
- Cloud consumption
- Lifecycle status
- App ownership
Technology leaders should also assess whether applications can support emerging capabilities like automation, analytics, and AI-enabled workflows, including agentic AI.
Step 2: Evaluate business value, technical health, and AI readiness
Once you’ve got your inventory, evaluate each application across three dimensions: business value, technical health, and strategic fit.
Applications that are critical to business operations—but suffer from aging architecture, limited scalability, poor user experience, or rising operational costs—are strong modernization candidates. Applications with low business value may be better retirement or consolidation targets.
Step 3: Assess security, resilience, and compliance exposure
Technology leaders should also examine operational and resilience risks. Legacy applications frequently rely on unsupported software, aging infrastructure, hard-to-find technical skills, or fragile integrations. These risks can increase the likelihood of outages, security incidents, compliance challenges, and business disruption. Applications supporting regulated processes or critical customer experiences should receive additional scrutiny.
Step 4: Identify technical debt, cloud spend, and support costs
Cost analysis should extend beyond maintenance spending to include cloud consumption, infrastructure costs, vendor licensing, and support effort. In many portfolios, a small number of applications account for a disproportionately high share of operating expenses even though they don’t deliver commensurate value.
Step 5: Map application and data dependencies
Technology leaders should document upstream and downstream dependencies, data flows, integration patterns, and critical business processes supported by each application.
Understanding these relationships helps identify modernization sequencing, reduce implementation risk, and avoid unexpected disruptions. Dependency mapping also reveals hidden opportunities to modernize multiple interconnected applications together rather than treating them as separate initiatives.
How dependency mapping improves modernization planning
- Benefit 1: Modernization sequencing with minimal friction
- Benefit 2: Implementation risk mitigation
- Benefit 3: Unexpected disruption solutions
- Benefit 4: Hidden opportunities
Examples 1–3
Identity before applications
Why it matters
Modernize the enterprise identity and access management platform before modernizing customer-facing applications that depend on it for authentication and authorization.
Integration layer before system replacement
Upgrade or modernize middleware, APIs, and integration services before replacing core ERP or CRM platforms that rely on those connections.
Data platform before AI initiatives
Modernize data warehouses, master data management, and data integration capabilities before deploying AI-enabled applications that depend on trusted, accessible data.
Benefit 2
Implementation risk mitigation
Examples 4–6
Undocumented integrations
Why it matters
A legacy billing application may have dozens of undocumented connections to downstream reporting, finance, and customer service systems that could fail.
Shared databases
Multiple applications may rely on the same database schema, creating unexpected compatibility issues when one application is upgraded.
Vendor dependencies
A modernization effort may depend on third-party software versions, APIs, or support agreements that are nearing end-of-life or require additional upgrades.
Benefit 3
Unexpected disruption solutions
Examples 7–9
Broken customer transactions
Why it matters
Modernizing an e-commerce platform inadvertently disrupts integrations with payment processing, order management, or inventory systems.
Reporting failures
Changes to application data structures cause executive dashboards, compliance reports, or operational analytics to stop functioning correctly.
Authentication outages
An application upgrade impacts single sign-on integrations, preventing employees, partners, or customers from accessing critical systems.
Benefit 4
Hidden opportunities
Examples 10–12
Consolidating duplicate platforms
Why it matters
Multiple business units may use separate workflow or case management applications that can be modernized and consolidated into a single platform.
Retiring legacy integrations
Modernizing a group of interconnected applications together may eliminate dozens of custom point-to-point integrations and reduce technical debt.
Creating shared business capabilities
Modernizing CRM, customer portals, and customer data platforms together can create a unified customer experience rather than improving each system independently.
Step 6: Rationalize redundant and low-value applications
Application rationalization helps identify opportunities to retire, consolidate, repurchase, or standardize systems across the enterprise:
- Lowers operating costs
- Simplifies support models
- Strengthens security
- Frees resources for higher long-term modernization value
Before investing in modernization, organizations should determine whether every application deserves continued investment (aka rationalization). This analysis can produce faster returns than jumping into just modernizing the applications themselves.
Years of acquisitions, departmental purchasing, leadership changes, and overlapping technology decisions create portfolios filled with dupe functionality, underutilized tools, and systems that don’t fully align (or align at all) with business priorities anymore.
Step 7: Build a value vs. effort prioritization framework
A practical prioritization framework helps organizations focus on initiatives that deliver the greatest business impact with manageable implementation effort. Successful leaders balance two things:
- Near-term wins like retiring redundant applications or modernizing high-cost systems to block leakage
- Longer-term investments in strategic platforms that improve agility, resilience, and future innovation capacity.
Step 8: Focus on quick wins, strategic platforms, and business-critical capabilities
Modernization doesn’t always mean refactoring. In many portfolios, the highest-return decision is to retire, consolidate, or repurchase (replace) an application. When the goal is a simpler, more resilient, and more cost-effective technology landscape that supports business outcomes, there are a number of levers to pull.
The five most important questions in the application modernization decision framework
Technology leaders should evaluate every application based on the answer to these five questions:
1. Does this application differentiate the business?
Applications that create competitive advantage justify deeper modernization investments.
- If the answer is yes, great. Modernize, refactor, or rearchitect.
- If you agree it’s no, consider SaaS as something to repurchase or a deeper investment elsewhere first.
2. Is the application creating operational risk?
If the application exposes the organization to security vulnerabilities, unsupported technology, architecture that’s aging out, technical skillset scarcity, and reliability issues, the application is a strong candidate for modernization. Naturally, the greater the risk—and the better you can quantify the risk for your board—the stronger your business case.
3. What is the application’s remaining business lifespan?
If it’s not obvious to every stakeholder, guide a conversation that focuses on modernization investments so they can see the alignment to future business needs.
- If the application will be strategically important for five or more years: consider deeper modernization investments.
- If the application is likely to be repurchased or retired within three years: minimize investment and focus on stability.
4. How difficult will modernization be?
Modernization effort varies dramatically depending on factors like:
- Integration complexity
- Data dependencies
- Technical debt
- Regulatory requirements
- Application architecture
Low-complexity applications may be suitable for rehosting or replatforming. Highly complex applications often require incremental refactoring over time.
However, technology complexity is only part of the equation.
The best modernization partners don't promise there won’t be any surprises. They demonstrate their competence and commitment when surprises come up.
Organizations should also evaluate delivery complexity, including how effectively modernization partners can navigate uncertainty, adapt to changing requirements, and maintain momentum when unexpected challenges emerge.
Signals for lower value or untrustworthy partnerships that add delivery complexity include:
- Slow-moving consultants
- Endless discovery phases
- Change-order-driven delivery models
- Junior-heavy staffing
- Teams incentivized to prolong work
- Bureaucratic governance that delays decisions
- Partners who treat uncertainty as a reason to stop instead of adapt
5. Where should you invest to deliver value fastest?
The best modernization programs evaluate each application individually and select the approach that balances value, cost, risk, and speed.
Most applications fall into one of three investment categories:
| If the application... | Consider... | Because... |
|---|---|---|
| Supports a unique business capability that creates competitive advantage | Improve | The application is strategically important, so enhancing it can generate additional business value |
| Delivers a commodity capability that others provide well | Repurchase | Buying a modern SaaS solution is often faster and cheaper than modernizing custom code |
| No longer provides meaningful business value | Retire | Eliminating the application reduces cost, complexity, risk, and technical debt |
Here are some examples of apps that are usually candidates for improvement, replacement/repurchasing, and retirement:
Improve
- Digital customer platforms
- Personalization engines
- Revenue-generating applications
- Proprietary business processes
Repurchase
- HR systems
- Collaboration tools
- Procurement systems
- Expense management platforms
Retire
- Duplicate applications
- Underutilized tools
- Legacy reporting platforms
- Systems supporting discontinued business processes
How do DevOps and automation improve modernization outcomes?
Modern observability and platform engineering practices provide real-time visibility into application performance and operational health. Together, they help teams identify issues earlier, improve reliability, and continuously optimize how software is built, deployed, and operated.
Modernizing applications without modernizing delivery is one of the fastest ways to recreate your legacy environment. You must modernize delivery, too.
In contrast, modernizing applications without modernizing delivery practices is one of the fastest ways to recreate tomorrow’s legacy environment. When organizations often invest in new platforms but don’t re-examine processes, speed gains are blocked, risk factors shift, innovation is still held up.
That’s why DevOps and automation are critical parts of the journey to Zero Legacy.
- Continuous integration and continuous delivery (CI/CD) pipelines automate testing, deployment, and quality controls, helping teams deliver changes faster and with greater confidence.
- Infrastructure as code (IaC) further strengthens consistency, reduces configuration drift, and creates repeatable, auditable environments that support resilience, compliance, and long-term scalability.
- Quality automation extends these practices by embedding automated testing, security scanning, and compliance checks directly into the delivery process. This reduces manual interventions, accelerates feedback loops, and helps teams identify issues before they reach production. The result is faster delivery, improved reliability, and a stronger foundation for continuous modernization.
- Organizations that combine modernization with DevOps transformation reduce operational risk, improve system resilience, and create a foundation for continuous improvement—freeing engineering teams to focus less on maintenance and more on delivering business value.