JCL Tutorial

JCL in Modern Environments

Discover how traditional JCL practices integrate with contemporary technologies, DevOps methodologies, and modernization efforts.

JCL in the Modern Enterprise

While JCL has been around since the 1960s, it continues to play a vital role in modern enterprise computing. Mainframe systems remain at the core of many large organizations' IT infrastructure, particularly in industries like banking, insurance, government, and transportation.

Rather than being replaced, JCL is being integrated with modern DevOps practices, automation tools, and cloud technologies to bridge the gap between legacy systems and contemporary software development approaches.

Key Modern JCL Topics

JCL and DevOps

Integrate JCL into modern CI/CD pipelines and DevOps workflows

Learn about JCL and DevOps

JCL and REXX

Enhance JCL with powerful REXX scripting capabilities

Learn about JCL and REXX

Migration Strategies

Approaches for migrating and modernizing legacy JCL

Learn about JCL Migration

Bridging the Old and New

Traditional JCL Environment

• Manual JCL editing in TSO/ISPF
• Paper-based change management
• Minimal version control
• Overnight batch processing windows
• Siloed operations and development teams
• Limited testing environments

Modern JCL Environment

• JCL in Git repositories with version control
• Automated testing and deployment
• CI/CD pipelines for mainframe code
• Integration with distributed systems
• DevOps culture and practices
• Automated validation and standards checking

Benefits of Modernizing JCL Practices

1Faster Delivery: Automate testing and deployment to reduce time-to-market for mainframe applications.
2Reduced Risk: Implement proper version control and automated testing to minimize production incidents.
3Knowledge Transfer: Bridge the gap between retiring mainframe experts and new developers with modern tooling.
4Cost Efficiency: Integrate mainframe operations with enterprise-wide automation to reduce operational costs.
5Agility: Respond more quickly to business needs with automated JCL generation and deployment.

Modern JCL Tools and Technologies

Tool/Technology	Purpose	Benefit
Git/GitHub/BitBucket	Version control for JCL	Change tracking, collaboration, and history
Jenkins/GitLab CI	Continuous integration	Automated testing and deployment of JCL
REXX Scripts	JCL generation and automation	Dynamic JCL creation based on conditions
Zowe CLI	z/OS access from command line	Integration with modern dev environments
JCL Analyzers	Static code analysis	Identify issues before submission
Conversion Tools	JCL migration assistance	Help with platform transitions

Learning Path

We recommend starting with JCL and DevOps to understand how traditional JCL fits into modern software development practices. Then explore JCL and REXX integration to learn automation techniques, followed by migration strategies to understand approaches for modernizing legacy JCL code.

Each topic provides practical examples and best practices to help you bridge the gap between traditional mainframe operations and modern software development methodologies.

Debugging & Troubleshooting JCL and DevOps