Executive summary

Nedbank, one of South Africa's four largest banks, faced mounting pressure from agile fintech competitors and the slow, manual processes of its legacy mainframe development. By adopting BMC AMI DevX solutions, Nedbank transformed its mainframe software delivery, cut deployment times from months to weeks, eliminated entire categories of manual work, and modernized its core banking applications—all while maintaining the reliability its customers depend on. The result is a self-sufficient, future-proof mainframe practice that keeps pace with the bank's distributed teams and its ambition to be the best bank in Africa.

Company overview

Nedbank Group is one of South Africa's four largest banks, with a growing presence across the continent through subsidiaries and strategic alliances. Its vision is to use financial expertise to do good for individuals, families, businesses, and society, delivering experiences that exceed client expectations.

At the heart of that mission sits the mainframe. It runs Nedbank's core banking products and handles the bulk of the bank's transaction processing—the engine behind every mobile payment, branch interaction, and record-breaking Black Friday.

Keeping that engine fast, reliable, and modern became one of the bank's defining technology challenges, and the start of a multi-year partnership with BMC.

The challenge

Nedbank began its DevOps journey more than six years ago, but the early focus was entirely on distributed systems. The prevailing assumption was that DevOps wasn't for the mainframe—an irony Olivier notes, given how closely the platform already resembled a cloud environment.

Meanwhile, the competitive landscape was shifting fast. Fintech startups, nimble and cloud-native, were entering the South African market and shipping new features at a pace the mainframe couldn't match.

"We very quickly realized that we couldn't leave the mainframe behind," Olivier says. The bank faced a perfect storm of challenges:

• Slow delivery. Releases followed a waterfall model, with deployment cycles stretching to two or three months. Shrinking deployment windows and ballooning deployment times made matters worse.
• Rigid tooling. Earlier attempts at modern tools proved too rigid for COBOL, making it difficult to cherry-pick changes or roll back a single program.
• Expansion across Africa. Extending into new regions demanded a configurable, component-based core rather than duplicated code for each market.
• An aging workforce and misconceptions. Persistent myths that the mainframe and COBOL were obsolete had slowed the influx of new talent, leaving the bank with a shrinking pool of specialists.
• Heavy manual overhead. Developers compiled change logs and program lists by hand on spreadsheets. A full-time team of two to three people existed solely to track program contention and coordinate deployments between teams.

Compounding the complexity, the bank's estate included some genuine monsters—core programs running as large as 500,000 lines of code within a total estate of roughly 20 million lines.

The risk was clear. Without change, Nedbank would fall behind more agile rivals while struggling to maintain a system that still carried the bulk of its processing.

The solution

Nedbank took a deliberate, multi-faceted approach and made culture as central as technology.

Rather than imposing new tools, the team ran a value stream mapping exercise that brought together developers, testers, database administrators, and systems programmers. Together they mapped the end-to-end process, identified pain points, and evaluated solutions side by side.

"If something is done with me, I get excited," Olivier says. "If something is done to me, no matter how good it is, I'm already apprehensive." That principle—"we didn't want to inflict change on our teams, we wanted to invite them on the journey"—shaped everything that followed.

After a rigorous evaluation against competing products, Nedbank selected BMC AMI DevX as the foundation of its modern mainframe development. Several factors set BMC apart:

• Flexibility for every developer. Support for traditional ISPF workflows as well as Eclipse- and VS Code-based development meant developers could work in the environment that best suits them.
• A unified, packaged experience. BMC AMI DevX Code Pipeline provides modern source code management, build, and deployment automation.
• COBOL-aware change management. Developers could easily move programs between containers, roll back a single program, and sequence copybooks and programs together.
• Open integration. API enablement let Nedbank orchestrate mainframe deployments alongside any other platform, integrating tools like SonarQube and, later, Azure DevOps.
• A responsive partner. When the team hit roadblocks, BMC took improvement opportunities seriously—a contrast, Olivier noted, with other vendors.

The rollout was aggressive but staggered. Working in ring-fenced code bases, the team migrated developers in stages—training each group before moving to the next—and completed the migration of roughly 250 mainframe developers in just six months. The actual migration for each team took only hours, followed by a few days of upskilling.

From there, Nedbank extended its modern practice across the software delivery lifecycle:

• Automated testing with BMC AMI DevX Total Test, using behavior-driven development to design tests before writing code. Total Test played "a massive role," even helping the team build test harnesses.
• Actionable metrics with BMC AMI zAdviser, delivering DORA metrics and industry benchmarks the bank had never had before. As Olivier noted, the team went from having almost no data to "such an abundance of metrics so easily."
• Code analysis and insight at both the application and system level through BMC AMI DevX Workbench and BMC AMI DevX Code Insights.  

With a modern pipeline in place, Nedbank turned to its core applications. The goal wasn't to rip out the mainframe but to modernize around it—"hollowing out the core" by externalizing business rules and pricing from monolithic COBOL programs into configurable, component-based, API-first services.

Critically, the bank resisted the temptation of a blanket conversion to Java. Its decisions were guided by a fit-for-purpose principle: keep core banking and payments—roughly 80 percent of the COBOL codebase—on the mainframe in COBOL, while selectively redesigning and rewriting a small set of applications in Java where it made sense.

"Mainframe has a purpose. It's got a place. For the right application, you can't beat it," Olivier says. "But there's a time and a place to move something to Java. The big lesson is fit for purpose."

The results

Nedbank's modernization delivered measurable gains across speed, quality, and efficiency.

• A single heartbeat. Mainframe teams now plan, sprint, and release in the same cadence as distributed teams, synchronizing the organization around one delivery rhythm.
• A modernized core.  Massive monolithic programs—some as large as 500,000 lines of code—are being broken into manageable, service-oriented components.
• 200% growth in API adoption. zOS Connect adoption grew roughly 200 percent in a year, enabling real-time, API-driven, channel-agnostic integrations.
• From months to weeks. Deployment cycles dropped from two or three months to a steady three-week average, with two-week sprints as the standard cadence. Urgent fixes that once strained the bank's service-level agreements can now reach production in as little as two minutes once a clean compile is ready.
• Dramatically faster delivery. The build-to-production process fell from hours to roughly 18 minutes.
• Manual work eliminated, not just reduced. Automated change tracking removed the developer admin burden entirely and freed the two-to-three-person team that had manually monitored contention to focus on higher-value work. Source-code-managing JCL eliminated manual updates and the errors that came with them.
• Higher quality. Change failure rates dropped immediately. For several consecutive months during the past year, the core banking team recorded zero fallbacks and zero regressions in production.

The business felt the impact where it matters most. Nedbank processed record transaction volumes during Black Friday with little to no interruption, and the core banking team won the company's Top Team Achiever award as a result.

The cultural shift proved just as valuable. Modern, intuitive tooling has begun to change how new talent views the platform—turning the "old" perception into genuine interest in mainframe careers.

Looking ahead

Nedbank set out to compete with the speed of fintech disruptors without sacrificing the reliability of the platform at its core. By pairing BMC AMI DevX solutions with a culture of inclusion and continuous improvement, the bank modernized both its development practice and its core applications—accelerating delivery, eliminating manual effort, raising quality, and future-proofing its talent pipeline.

The journey is far from over. Nedbank continues to expand automated testing, extend database change automation through its pipeline, and apply BMC AMI DevX zAdviser insights to guide further modernization—all in pursuit of its ambition to be the best bank in Africa and beyond, measuring every step against tangible business value.

"Continuous improvement is the key to unlocking DevOps," Olivier says. "If I can make small incremental improvements as I go along, before I know it, I'm in a much better space than I was years ago."

It's a principle that has turned a legacy mainframe into a modern, measurable engine for innovation.