Accelerating Legacy Modernization with Generative AI: From Mainframe to Cloud-Native with Ask Bode

Modernizing legacy systems—especially mainframes—remains one of the most formidable challenges for large enterprises. These decades-old platforms, while reliable, often stand in the way of agility, innovation, and cost efficiency. The journey from monolithic, on-premises architectures to modern, cloud-native platforms is complex, resource-intensive, and fraught with risk. Generative AI, and specifically Ask Bode from Publicis Sapient, is redefining how organizations approach this critical transformation, delivering speed, transparency, and measurable business value.

Legacy systems are the backbone of mission-critical business processes in industries like insurance and financial services. However, their limitations are increasingly apparent: high maintenance costs, limited scalability, and inflexibility that stifles digital transformation. For organizations seeking to unlock new value, reduce operational costs, and accelerate innovation, modernizing these systems is no longer optional—it’s essential.

Generative AI, powered by advanced large language models (LLMs), is revolutionizing the modernization process. Ask Bode, Publicis Sapient’s enterprise-grade generative AI solution, leverages the latest advancements in AI to analyze, deconstruct, and refactor legacy codebases with unprecedented speed and accuracy. By automating key steps in the modernization journey, Ask Bode enables organizations to:

• Comprehend and decode complex legacy programs: AI models rapidly analyze mainframe code, uncovering business logic, dependencies, and data flows that would take human teams months to document.
• Generate functional specifications and documentation: Ask Bode automates the creation of detailed, traceable documentation, improving transparency and reducing the risk of knowledge loss.
• Refactor and transition code to modern architectures: The platform assists in translating legacy code into modern languages and frameworks, supporting cloud-native deployment and future-proofing applications.
• Automate testing and validation: AI-generated unit tests and automation scripts accelerate quality assurance, ensuring that modernized applications meet business and technical requirements.

Ask Bode is not a black box. Its “glass box” approach means every step is transparent, customizable, and designed to integrate seamlessly with your existing tools and workflows. Hosted on leading cloud platforms and built on Publicis Sapient’s award-winning Bode platform, Ask Bode delivers:

• 3x Faster Migration Timelines: For a global Fortune 500 company, Ask Bode enabled cloud developers to use private LLMs to deconstruct legacy mainframe programs, resulting in migration efforts that were three times faster than traditional methods.
• Reduced Costs and Effort: By automating code analysis, documentation, and refactoring, organizations have significantly lowered the manual effort required, translating into substantial cost savings.
• Improved Maintainability and Quality: The generation of functional specifications and automated test cases ensures that modernized applications are easier to maintain, enhance, and audit—laying the foundation for continuous innovation.

• Global Fortune 500 Modernization: Facing the imperative to accelerate mainframe modernization, a Fortune 500 enterprise partnered with Publicis Sapient to deploy Ask Bode. The solution enabled cloud developers to deconstruct legacy programs using private AI models, fine-tune operationalization through iterative sprints, and deliver functional specifications that improved traceability and quality. The result: a threefold increase in migration speed, reduced effort, and a modern tech stack that is easier to maintain and enhance.
• Industry-Wide Efficiency Gains: Across more than 100 end-to-end modernization experiments, Publicis Sapient’s generative AI accelerators—combined with platforms like PSChat and Bodhi—have consistently delivered faster timelines, lower costs, and higher-quality outcomes for clients in insurance, financial services, and beyond.

Ask Bode’s impact extends beyond speed and cost. Its technical and business benefits include:

• Transparency and Trust: The glass-box design ensures every AI-driven decision is explainable and auditable, a critical requirement for regulated industries.
• Seamless Integration: API-based architecture allows Ask Bode to connect with existing data, compliance, and operational systems, minimizing disruption and maximizing value.
• Responsible AI Practices: Customizable guardrails, automated compliance checks, and human-in-the-loop oversight ensure that modernization is both rapid and responsible.
• Cloud-Native Security: Deployable on leading cloud platforms, Ask Bode leverages enterprise-grade security features—identity and access management, encryption, audit trails, and data residency controls—to ensure compliance with industry regulations.
• Continuous Improvement: Performance data and feedback loops enable ongoing refinement of models and processes, ensuring sustained effectiveness and compliance.

Publicis Sapient’s approach to generative AI-driven modernization is holistic and responsible. Every engagement is guided by best practices in responsible AI, data privacy, and security. Human experts remain in the loop, ensuring that AI-generated outputs are validated, compliant, and aligned with business objectives. Our SPEED framework—Strategy, Product, Experience, Engineering, Data & AI—ensures that every modernization initiative is strategically aligned, technically robust, and engineered for scale.

With over 30 years of digital transformation experience, Publicis Sapient is uniquely positioned to help organizations unlock the full potential of generative AI for legacy modernization. Our differentiators include:

• End-to-end partnership: From readiness assessment and strategy to rapid prototyping, implementation, and scaling, we guide clients through every stage of their modernization journey.
• Industry-specific accelerators: Ask Bode and our suite of AI tools are designed for speed, security, and compliance, tailored to the unique needs of each client.
• Measurable, responsible outcomes: We focus relentlessly on delivering tangible business value—faster migration, reduced costs, improved maintainability, and enhanced agility—while embedding ethics and governance at every step.

Generative AI, powered by Ask Bode, is transforming the way enterprises modernize legacy applications. Whether you’re looking to migrate from mainframe to cloud-native, automate documentation, or future-proof your technology stack, Publicis Sapient is your trusted partner for AI-driven modernization—securely, responsibly, and at speed.

Connect with our experts to discover how Ask Bode can unlock new value for your business and accelerate your path to a modern, agile enterprise.

Relevant Links

• Ask Bode: Accelerating Enterprise-Scale Generative AI Deployment
• L’IA Générative : Un Accélérateur de Transformation pour les Entreprises Européennes (Europe)
• Generative AI en Industrias Reguladas de América Latina: Cumplimiento, Seguridad e Innovación Responsable (LATAM)
• Generative AI en Industrias Reguladas de América Latina: Cumplimiento, Seguridad e Innovación Responsable (LATAM)
• Generative AI for Regulated Industries: Ensuring Compliance, Security, and Scale with Ask Bode
• Generative AI en Industrias Reguladas de América Latina: Cumplimiento, Seguridad e Innovación Responsable (LATAM)
• L’IA Générative : Un Accélérateur de Transformation pour les Entreprises Européennes (Europe)
• Ask Bode: Accelerating Enterprise-Scale Generative AI Deployment