In the era of agile and DevOps transformation, enterprises face increasing pressure to modernize not only their applications but also the processes used to build, test, and deploy them. This is especially true for organizations running mission-critical workloads on IBM z/OS systems. Traditional mainframe build processes—reliant on static JCL scripts and manual compile-link procedures—no longer align with modern development practices.
Enter IBM Dependency Based Build (DBB), a cornerstone in modernizing mainframe delivery pipelines. DBB provides a smart, dependency-aware, and programmable framework for compiling and linking z/OS applications with automation and precision. With the release of DBB v3, the tool has evolved further, bringing in features that strengthen its integration with CI/CD ecosystems and enhance developer productivity.
🔍 What is IBM Dependency Based Build?
IBM Dependency Based Build (DBB) is an automation tool for compiling and linking applications on z/OS. It supports a Groovy-based scripting interface to define build logic, track dependencies between source components, and perform incremental builds—similar to how modern build tools like Make, Gradle, or Maven work.
It’s designed to bridge the gap between legacy mainframe processes and modern DevOps, enabling developers to focus on application logic while automating repetitive and error-prone build tasks.
🆕 What’s New in DBB v3?
Released as part of IBM’s ongoing enhancements to support DevOps on z/OS, DBB v3 introduces powerful new features that improve flexibility, efficiency, and integration.
✳️ Key Features of DBB v3:
- New zBuilder
Build configuration is defined in YAML files under the control of the build engineering team. - Enhanced Build Reporting and Logging
The latest version includes structured build logs, performance metrics, and failure tracking—helping teams better analyze build trends and errors. - Parallel Build Support
DBB v3 offers multi-threaded build execution, which significantly reduces build time for large codebases. - Improved Git Integration
Enhanced compatibility with GitHub, GitLab, and Bitbucket repositories enables seamless fetch, version control, and webhook-triggered builds. - Dependency Scanning Improvements
More granular support for understanding COBOL copybooks, PL/I includes, and Assembler macros—ensuring accurate build order determination.
🧱 How DBB Works: A DevOps-Ready Build Model
The process of building mainframe applications using DBB typically follows this flow:
- Setup and Configuration
- Install DBB and the IBM Language Environment (LE) runtime.
- Configure DBB_HOME and define datasets, source libraries, and compilers.
- Create Build Scripts
- Write Groovy-based scripts to:
- Define source elements (COBOL, PL/I, Assembler, IMS)
- Specify compile options and link-edit rules
- Configure outputs such as load modules or object code
- Define Dependencies
- DBB builds a dependency graph based on includes, macros, and call relationships.
- Supports incremental builds—only recompiling changed or dependent modules.
- Execute Builds
- Trigger builds via CLI or CI/CD pipeline (Jenkins, GitHub Actions, GitLab CI, Azure DevOps).
- DBB uses the dependency map to compile, link, and generate executable artifacts.
- Review Reports
- Build reports are generated in JSON or HTML, highlighting:
- Success/failure status
- Performance metrics
- Module-level logs
🔗 CI/CD Integration with DBB
One of the strongest aspects of DBB is its seamless integration with popular CI/CD platforms, including:
- Jenkins Pipelines: Trigger builds from Git commits, execute Groovy DBB scripts, and deploy automatically.
- GitHub Actions: Use DBB runners on z/OS to automate compile and link based on Git events.
- GitLab CI: Integrate build jobs into GitLab pipelines using custom shell runners.
- Azure DevOps: Invoke DBB scripts via service hooks or custom agents for full-cycle automation.
✅ Benefits of Adopting DBB
- Faster Time-to-Market: DBB’s automation reduces manual errors and accelerates delivery cycles.
- Smarter Incremental Builds: Saves compute resources by only building what’s changed.
- Better Team Collaboration: Developers use modern tools (like Git + DBB) while backend teams ensure system compliance.
- Standardized DevOps Workflow: Integrate with open tools and platforms to unify mainframe and distributed DevOps practices.
- Audit-Ready Reporting: Detailed logs and build reports meet enterprise compliance needs.
🎯 Use Cases
- Banking: Automate COBOL batch application builds as part of nightly Jenkins jobs.
- Insurance: Enable Git-triggered DBB builds for policy administration systems.
- Retail: Integrate DBB with UCDz for full promotion across test and production LPARs.
🏁 Final Thoughts
As enterprises modernize their IT infrastructure, IBM Dependency Based Build (DBB) becomes a critical enabler for agile, automated, and scalable mainframe development. The introduction of DBB v3 takes this capability further by improving performance, visibility, and integration.
Whether you’re starting your DevOps journey on z/OS or enhancing existing workflows, DBB provides the foundation for fast, reliable, and DevOps-friendly builds.
📩 Ready to Modernize Your Mainframe Build Process?
At VRNexGen Technologies, we help clients implement and optimize DBB-based pipelines tailored to their environments. From installation to pipeline integration and developer training, we ensure your DevOps journey is future-ready.
📧 Contact us: sales@vrnexgen1.com
🌐 Visit: www.vrnexgen1.com
VRNexGen Technologies – Modernizing Mainframe Development for the DevOps Era
