Cloud Native Development Plan: How to Transform Legacy Apps

What Is Cloud Native Development?

Cloud native development is an approach to building and running applications that fully leverage the advantages of cloud computing. Unlike traditional applications that may be simply “moved” to the cloud, cloud native applications are designed with scalability, automation, and resilience in mind.

Key characteristics include:

For legacy systems, adopting cloud native principles doesn’t always mean a complete rebuild. It often involves selectively modernizing components, aligning them with business priorities, and ensuring a smooth transition with minimal disruption.

Steps to Transform Legacy Applications into Cloud Native Systems

Modernizing legacy systems is not about flipping a switch—it’s about following a clear, structured process. Each step builds on the previous one, helping you balance technical priorities with business goals. The following eight steps provide a practical roadmap to guide your cloud native journey, from initial assessment to full-scale optimization.

Image showing how to modernize legacy apps in the cloud

Step 1. Assess Your Legacy Application

The first step is to understand what you are dealing with. Every legacy system is different. Some may be monoliths with tightly coupled modules. Others may depend on old databases, APIs, or on-premise servers.

Start by asking simple questions:

A good assessment includes both technical and business perspectives. From the technical side, make a list of dependencies, frameworks, runtime versions, and data sources. From the business side, identify requirements such as uptime targets, compliance, and cost expectations.

The outcome of this step should be a clear picture of the system’s current state and a list of goals for the migration. For example: reduce downtime during updates, improve scalability, or lower hosting costs.

Recommended Read: Cloud-Native vs. Cloud-Based Applications: What’s the Difference?

Step 2. Choose the Right Migration Strategy

Once you know the system, you need to decide how to move it. Not every application needs the same level of change. There are 7 Rs of cloud migration, of which the 4 most common strategies are:

The choice depends on budget, time, and long-term business goals. For many organizations, the path is a mix: lift some parts, replatform others, and refactor the most critical modules — a crucial step in any legacy application modernization initiative. The key is to prioritize. Start with high-value components where modernization brings the most benefits.

Step 3. Plan Your Architecture

Cloud native development is not only about moving code. It also requires carefully designing cloud architecture so different parts of the system work together seamlessly.

Cloud native development is not only about moving code. It also requires carefully designing a cloud modernization roadmap and cloud architecture so different parts of the system work together seamlessly. This stage is also where containerization and microservices adoption becomes a key architectural decision.

At this stage, define which modules can remain monolithic for now and which ones should become microservices. Decide how services will communicate, usually through APIs or an event bus.

Data migration is a big challenge. Some applications depend on large monolithic databases. Splitting them can take time.

Common patterns include:

Also think about integration with other systems. A clear API contract helps ensure that new services can interact smoothly with old ones during the transition.

A well-defined architecture plan avoids unnecessary rework later and serves as the foundation for the following steps.

Step 4. Containerize the Application

Containers are at the heart of cloud native development. They allow applications to run consistently across environments. Unlike traditional deployment on servers, containers package everything needed: runtime, libraries, and configuration.

To containerize a legacy app:

Containerization provides portability. You can run the same container on a developer’s laptop, in staging, or in production. Partnering with a cloud native app development company at this stage ensures the right containerization approach, aligning with your DevOps and cloud transformation consulting goals. It also simplifies scaling because multiple copies of a container can run in parallel when demand increases.

Step 5. Adopt Orchestration and Infrastructure

Running a few containers is simple. Running hundreds is not. This is where orchestration comes in.

Kubernetes has become the standard platform for managing containers at scale. It handles scheduling, scaling, self-healing, and networking. Most cloud providers offer managed Kubernetes services, which reduce operational overhead.

In addition to orchestration, think about infrastructure management. Infrastructure as Code (IaC) tools such as Terraform, Pulumi, or Helm charts allow teams to define environments in code. This brings repeatability and reduces manual errors.

For advanced traffic management, security, and observability, a service mesh like Istio or Linkerd can help. However, it is best to introduce these only when necessary. Keep the initial setup simple and expand later as needs grow.

Step 6. Build CI/CD and GitOps Pipelines

Modern applications need automated delivery pipelines. Continuous Integration (CI) ensures every code change is tested and built into a container image while Continuous Deployment (CD) ensures that tested changes reach production reliably.

A typical pipeline includes:

GitOps takes this one step further. Instead of manually applying configurations, the desired state of the system is stored in Git. For businesses aiming to accelerate digital transformation, implementing CI/CD with GitOps is a critical capability — and can be streamlined with DevOps and cloud transformation consulting expertise. Tools such as Argo CD or Flux monitor the repository and apply changes automatically. This approach provides transparency, version control, and easy rollback.

It is recommended to partner with top cloud consulting services providers like TenUp for the effective design and implementation of these pipelines.

Related Read: How to Build Scalable Cloud-Based Apps: A Step-by-Step Beginner’s Guide

Step 7. Enable Observability and Security

Migrating to the cloud is not only about deploying applications. You also need to monitor, secure, and manage them.

Observability means collecting logs, metrics, and traces. These three pillars give insight into system health and help detect issues quickly. Tools like Prometheus, Grafana, and OpenTelemetry are commonly used.

Security must be addressed early. Key practices include:

Defining Service Level Objectives (SLOs) and tracking error budgets help align system performance with business expectations. This way, the migration not only modernizes technology but also improves reliability.

Step 8. Execute Incremental Migration and Optimize

The last step is to actually move workloads. A proven method is the Strangler Fig pattern. Instead of rewriting everything, you build new services alongside the old system. Over time, traffic is routed from the legacy modules to the new ones until the old system can be retired.

Use deployment strategies that reduce risk:

Once the migration is complete, focus on optimization. Monitor resource usage, scale efficiently, and control costs. Cloud native development makes it possible to continuously adjust and evolve the system instead of letting it grow stale.

Finally, decommission the legacy components step by step. This avoids paying for duplicate infrastructure longer than necessary.

TenUp's Take: Always align your migration strategy with business goals, not just technology trends. Start with the most valuable modules, validate each stage with testing, and invest in team training. This ensures smoother adoption and avoids costly setbacks.

Business Benefits of Cloud Native Development

Modernizing legacy applications isn’t just an IT project — it’s a business-critical initiative. Cloud native development services help enterprises modernize legacy systems, reduce costs, accelerate innovation, and stay competitive. Here’s why businesses invest in enterprise application modernization:

Challenges in Modernizing Legacy Systems with Cloud Native Development

Modernizing legacy applications is rewarding, however it is not without obstacles. Here are some common issues and ways to deal with them.

Image showing challenges in smooth transition from legacy to cloud

Challenge #1: Legacy Code Complexity and Hidden Dependencies

Many legacy applications have grown over years with little documentation. Dependencies may be hardcoded, or critical modules may rely on outdated libraries. This makes moving to cloud native development more difficult.

Solution: Start with a dependency analysis using static code tools and runtime tracing. Document critical paths and isolate them first. Breaking the work into smaller modules prevents surprises later.

Challenge #2: Data Migration Difficulties

Most legacy systems run on large monolithic databases. Splitting them into services can be challenging because data models are often tightly coupled.

Solution: Use patterns like change data capture (CDC) to stream updates into the new database while keeping the old one active. Migrate data incrementally instead of all at once. Test thoroughly to ensure consistency.

Challenge #3: Skills Gap in Cloud Native Tools

Teams used to traditional development may lack experience with containers, Kubernetes, or DevOps pipelines. This slows progress and increases mistakes.

Solution: Provide targeted training and start with a pilot project. Hands-on learning with a smaller module helps the team gain confidence before handling large-scale migration. Partnering experienced engineers with newcomers also shortens the learning curve.

Challenge #4: Cost Overruns if Scaling Is Not Managed

Cloud native systems can scale easily, but without limits, they can generate unexpected bills. Uncontrolled resource usage often surprises teams after migration.

Solution: Set resource quotas and use cost monitoring tools such as KubeCost or cloud provider dashboards. Review usage regularly and right-size workloads. Automating scale-down policies during low traffic hours also helps.

Challenge #5: Security Blind Spots with Distributed Systems

Cloud native development spreads workloads across services, which increases the attack surface. Misconfigured access or weak container images can expose systems.

Solution: Integrate security from the start. Scan container images, enforce RBAC, and use secret management tools. Regular audits and monitoring reduce risks before they become incidents.

Partner with TenUp Soft for Successful Cloud Native Development

Modernizing legacy applications through cloud native development is not about a quick overhaul. It is about steady and intentional progress. The 8 steps you have just gone through form a clear playbook that keeps operations safe and scalable throughout. However, every organization faces its own challenges, such as hidden dependencies, data migration hurdles, or cost and security concerns. This is where TenUp Soft comes in.

We at TenUp Software Services have deep experience in cloud solutions, legacy migration, DevOps, and infrastructure automation. Our experts understand how to move systems forward without losing grip on day-to-day delivery and provide hands-on support across any of these phases. Get in touch with our experts today to start your cloud native journey.