From Application Modernization to Cloud-Native Delivery on AWS

Legacy technology rarely slows down just one part of the business. It affects how quickly teams can ship, how reliably platforms perform, how easily data can move, how securely environments can scale and how confidently leaders can invest in what comes next. That is why modernization cannot stop at code conversion alone. Real transformation happens when application refactoring, cloud migration, DevOps, testing, observability and managed services are treated as one connected journey.

Publicis Sapient helps enterprises make that journey on AWS. We bring together strategy, engineering, cloud foundations and AI-powered accelerators to help organizations move from aging systems and fragmented delivery models to secure, scalable, cloud-native operations built for speed, resilience and quality. The goal is not simply to replace old code. It is to establish a modern delivery model that can keep improving long after migration is complete.

Many organizations begin with a familiar problem: legacy applications are expensive to maintain, difficult to change and dependent on scarce skills. But beneath that challenge are other constraints that slow transformation just as much—siloed infrastructure, inconsistent environments, manual release processes, limited test automation and poor visibility into production performance. Rewriting code without addressing those conditions often recreates the same friction in a newer stack.

Publicis Sapient approaches modernization differently. Across our SPEED capabilities—Strategy, Product, Experience, Engineering, and Data & AI—we connect business goals to execution across cloud strategy, migration, modernization, security, automation and operations. On AWS, that means building a practical path from legacy systems to cloud-native delivery, where every stage reinforces the next: strategy informs mobilization, mobilization accelerates build, build enables migration, migration supports continuous delivery and observability strengthens production operations.

Successful modernization begins with clarity. We help enterprises assess their current estate, identify the business and technology outcomes that matter most and shape a roadmap for migration and modernization that is tied to value rather than activity. That includes defining the right target architectures, sequencing work for measurable momentum and aligning cloud decisions to long-term agility, resilience and cost efficiency.

Using AWS migration best practices, we help clients establish a smoother path into the cloud while planning for the capabilities they will need to run modern platforms at scale. For many organizations, that also includes foundation setup, database planning, infrastructure design, secure architecture and FinOps management from the start. Where appropriate, AWS migration funding can help reduce transition cost and accelerate execution.

Cloud-native delivery depends on more than a landing zone. It requires an environment designed for continuous change. Publicis Sapient helps organizations build secure, scalable AWS foundations that support modern engineering practices from day one. Our cloud infrastructure work spans strategy, build, security and migration so enterprises can dismantle legacy silos, improve collaboration and scale resources dynamically as demand changes.

Security is embedded throughout the journey, not bolted on at the end. We work across data security, cloud-native security, security mesh and network security to help organizations modernize with confidence while reducing operational risk. The result is an AWS environment prepared not only for migration, but for sustained delivery, governance and growth.

Application modernization is often where programs lose momentum. Teams must interpret legacy logic, document behavior, define a target state and refactor applications for modern architectures—all while protecting quality and keeping delivery moving. Publicis Sapient uses AI-assisted modernization to make that process faster, more traceable and more practical for enterprise teams.

Sapient Slingshot modernizes legacy systems by turning existing code into verified specifications and generating modern software with full traceability. Built off Bodhi, our enterprise-ready AI platform on AWS, Sapient Slingshot helps accelerate both modernization and the software development lifecycle. Using large language models, contextual knowledge and pre-built prompt libraries—with human intervention built into the process—we can analyze code, generate documentation for the target state, transition legacy applications to modern architectures and automate testing activities.

The outputs are designed for delivery teams to use immediately: feature summaries, detailed specifications, transformed architecture, test cases, unit tests and automation test scripts. That creates a stronger bridge from legacy analysis to implementation, reducing ambiguity while improving quality and speed. In our analysis of more than 100 end-to-end experiments using AI-enabled modernization accelerators, we saw the potential for more than 50% reduction in modernization costs, 50% fewer defects with broader coverage of requirements and test cases, and a 50% increase in migration speed. Actual outcomes vary by client context, but the pattern is clear: AI is most valuable when it is embedded in a governed modernization process, not used as a standalone shortcut.

Modern applications need modern delivery practices. Publicis Sapient helps enterprises improve DevOps maturity so modernization does not end with a technical migration but evolves into a faster, more reliable way of working. We support DevOps engineering maturity assessments and strategy development to benchmark the current state, define improvement goals and create actionable plans for change.

From there, we help standardize hosting, implement infrastructure as code and configuration management, and build environments that can be provisioned and managed at scale. Continuous integration, deployment and delivery practices help teams release with greater speed and confidence. Code management and standardization improve governance and developer productivity. Agile DevSecOps embeds security throughout the software development lifecycle with a shift-left mindset and a zero-trust foundation.

This is where modernization starts to become an operating model advantage. Refactored applications move faster because the surrounding delivery system is built for change.

Cloud-native delivery requires quality and operational excellence from the beginning. Publicis Sapient helps clients automate validation within the delivery pipeline using AI-assisted generation of test cases, unit tests and automation scripts to expand test coverage and reduce defects. That means testing is not a downstream bottleneck. It becomes a built-in mechanism for protecting quality as delivery speeds up.

Once workloads are running in AWS, full-stack observability becomes essential. We provide comprehensive monitoring, logging, alerting, reporting and dashboarding that give teams meaningful visibility into application and infrastructure performance. With better insight into production behavior, organizations can identify issues sooner, improve reliability and continuously optimize the environment over time.

And for enterprises that need ongoing support after migration, our AWS managed services provide proactive and preventative capabilities that help reduce risk, refine cloud environments continuously and free internal teams to focus more of their effort on innovation instead of routine operational overhead.

The real measure of modernization is not whether workloads moved. It is whether the business now operates with less friction and more momentum. Publicis Sapient helps enterprises modernize faster, lower transformation costs and improve delivery confidence through secure AWS foundations, AI-assisted modernization, automated engineering practices and stronger production operations.

That value shows up across the journey: faster migration timelines, better traceability from legacy code to modern specifications, expanded test coverage, stronger application performance, more resilient operations and lower delivery effort. In AWS-related client work, Publicis Sapient has helped organizations achieve outcomes such as 3x faster migration in legacy modernization, 20% cost optimization with more than 75% enhanced application performance in cloud transformation, and 50% reductions in DevOps effort along with improved cost efficiency and shorter infrastructure setup times.

Publicis Sapient combines deep cloud, engineering and AI expertise to help enterprises move from strategy to execution with less friction. As an AWS Premier Tier Services Partner with broad AWS specializations, more than 2,000 tech and business accreditations, more than 1,400 AWS associate certifications and 3,000 generative AI-enabled consultants, we bring both platform strength and hands-on transformation experience. We also support cloud and infrastructure services for more than 150 clients across major industries.

What differentiates our approach is connection. We do not treat application modernization, cloud migration, DevOps transformation and production operations as isolated workstreams. We integrate them into one practical transformation model that helps enterprises build secure AWS foundations, modernize legacy systems with speed and traceability, and establish delivery practices that continue improving after go-live.

From roadmap to mobilization, build to migration, testing to observability and managed operations to ongoing optimization, Publicis Sapient helps turn AWS into a modernization engine. The result is not just new code in a new environment. It is a cloud-native delivery capability designed to help the business move faster, operate more resiliently and scale quality with confidence.

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