How TIAA Modernized Legacy Systems with its TETRIS Cloud and AI Project

When Sastry Durvasula joined TIAA in early 2022, he saw an organization fighting against outdated legacy technologies and in need of a major IT refresh. To secure business growth and tackle mounting operational risks, the nonprofit launched the Technology Ecosystem Transformation, or TETRIS, an ambitious multi-year initiative designed to modernize core IT stacks, slash technical debt, and deploy cloud-native architecture across major lines of business.

Decommissioning Technical Debt and Reengineering the Core

In 2022, just prior to the launch of TETRIS, over 80 percent of TIAA’s IT workloads resided in fragmented, end-of-life platforms. This legacy footprint created severe operational risks, compromised system resilience, and severely restricted the organization’s capacity to innovate. Durvasula, TIAA’s chief operating, information, and digital officer, pitched a three-pronged strategy to the board focused on powering business growth, fueling continuous innovation, and systematically transforming the IT core.

Phase one of the project kicked off in 2023, focusing entirely on foundational technology modernization. TIAA successfully rolled out 10 new enterprise platforms—including a modern data cloud and an enterprise design studio—earning the initiative a CIO 100 Award in 2025. By late 2024, the organization transitioned into phase two, which shifted the architectural focus from pure IT modernization toward outcome-driven business execution.

Through TETRIS phase two, TIAA cut its legacy technical debt nearly in half. The transformation consolidated 17 disparate design systems, eliminating inconsistent user experiences across digital products, accelerating time-to-market for new launches by 35 percent, and introducing robust multi-lingual capabilities that expanded accessibility to more than 185,000 non-English-speaking customers.

Driving Business Capability Through Cloud and APIs

Technical modernization under TETRIS involved far more than a simple lift-and-shift of virtual machines. TIAA combined multiple legacy middleware systems and disparate data lakes, migrating core mainframe applications and data center infrastructure to the cloud.

This architectural overhaul directly empowered the business to ship advanced digital products. Most notably, the revamped infrastructure enabled the launch of the MyChoice Multi-Year Guaranteed Annuity product. It also birthed the TIAA Gateway portal, an API-based architecture designed to seamlessly integrate with external partners across retirement and wealth planning using industry standards.

Phase two scaled these operational wins into 87 distinct business use cases across all primary lines of the enterprise. For an institution operating systems designed when the internet just came along, this capability leap represents one of the largest leapfrog moments in company history, culminating in a CIO 100 Award in 2026.

Metrics, Transparency, and Culture Change

Pulling off a multimillion-dollar architectural overhaul without losing executive backing requires rigid discipline around performance indicators. Project leaders deliberately structured phase one metrics around enterprise-grade platform delivery and infrastructure migration objectives, decoupling them from immediate business objectives. Phase two metrics, conversely, pivoted sharply toward measurable business outcomes and direct ROI.

Durvasula emphasizes that transparency with the board is non-negotiable when dealing with complex enterprise programs. “Not everything is as pretty as it sounds in an awards application,” Durvasula notes, explaining that teams must be honest about which metrics or KPIs can be delivered in early years versus when true business scale will manifest.

Beyond the silicon and software layers, TIAA recognized that retiring decades-old systems required an aggressive change management strategy. Rather than letting institutional talent become obsolete alongside legacy infrastructure, leadership established a multi-disciplinary team focused on breaking down organizational silos and driving internal upskilling. Employees were encouraged to combine their deep functional business knowledge with modern technical competencies, transforming a potential workforce crisis into an enterprise-wide cultural renewal that rode the wave of the recent artificial intelligence boom.