COBOL Legacy Benchmark Suite: Investment Portfolio Management System

A production-grade implementation of an Investment Portfolio Management System designed to challenge and benchmark Large Language Model (LLM) translation tools, specifically for COBOL modernization efforts.

Project Overview

This project presents a comprehensive COBOL-based system that simulates the complexity of real-world legacy applications. Developed using Anthropic Claude 3.5 Sonnet over five sprints, it serves as a robust test case for evaluating and fine-tuning LLM translation tools aimed at modernizing COBOL codebases.

Purpose

• Benchmarking LLMs: Provides a complex, production-grade COBOL codebase to assess the capabilities of LLMs in translating legacy code to modern languages like Java or C#.
• COBOL Modernization Reference: Serves as a detailed example for the COBOL modernization community, addressing the scarcity of publicly available, complex COBOL projects.
• LLM Development and Testing: Aids in the development and fine-tuning of LLM translation tools by offering realistic challenges beyond simplistic code snippets.

Key Features

• Complex Business Logic: Implements full transaction processing, portfolio management, and financial calculations.
• Comprehensive System Architecture: Includes batch processing, online transaction processing, reporting, utilities, and testing components.
• Production-Grade Standards: Follows industry best practices for error handling, data validation, security, and performance optimization.
• Mainframe Environment Simulation: Emulates key features of mainframe environments, exercising COBOL and z/OS functionalities.

High-Level Description

The system simulates an investment portfolio management application that:

• Manages portfolios and transaction histories.
• Processes financial transactions and updates positions.
• Generates reports on positions, audits, and system statistics.
• Supports online inquiries for portfolio positions and transaction histories.

While it is not intended for actual deployment, it mirrors the complexity and structure of real-world COBOL applications found in mainframe environments.

Development Approach

• LLM Pair Programming: Developed collaboratively with Anthropic Claude 3.5 Sonnet, turning requirements into design and code.
• Five Sprints Execution: Completed over five development sprints, each focusing on different system components.
• Best Practices Implementation: Adheres to standard mainframe development patterns and COBOL coding standards.
• Comprehensive Documentation: Includes detailed documentation to aid understanding and facilitate translation efforts.

Project Structure

project-root/
├── documentation/          # Project documentation
│   ├── technical/         # Technical documentation and architecture
│   ├── operations/        # Operational guides and specifications
│   ├── user/              # User documentation and guides
│   └── assets/            # Shared documentation assets
│
└── src/                   # Source code root
    ├── programs/         # COBOL source programs
    │   ├── batch/       # Batch processing programs
    │   ├── online/      # Online transaction programs
    │   ├── utility/     # Utility programs
    │   ├── test/        # Test programs
    │   ├── common/      # Shared utility programs
    │   └── portfolio/   # Portfolio management programs
    │
    ├── copybook/         # COBOL copybooks
    │   ├── batch/       # Batch processing copybooks
    │   ├── online/      # Online processing copybooks
    │   ├── db2/         # Database-related copybooks
    │   └── common/      # Shared system copybooks
    │
    ├── database/         # Database definitions
    │   ├── vsam/        # VSAM file definitions
    │   └── db2/         # DB2 table and index definitions
    │
    ├── jcl/              # Job Control Language scripts
    │   ├── batch/       # Batch processing jobs
    │   ├── utility/     # Utility and maintenance jobs
    │   ├── test/        # Test execution jobs
    │   └── portfolio/   # Portfolio management jobs
    │
    ├── maps/             # BMS screen definitions
    ├── cics/             # CICS resource definitions
    └── templates/        # Code templates and standards

System Architecture Overview

The system comprises several key components:

• Batch Processing Layer: Handles transaction validation (TRNVAL00), position updates (POSUPD00), and history loading (HISTLD00).
• Online Layer: Provides inquiry capabilities through INQONLN, allowing users to view portfolio positions and transaction histories.
• Utility Programs: Include file maintenance (UTLMNT00), system monitoring (UTLMON00), and data validation (UTLVAL00).
• Reporting System: Generates reports on positions (RPTPOS00), audits (RPTAUD00), and system statistics (RPTSTA00).
• Test Components: Consist of test data generation (TSTGEN00) and test validation (TSTVAL00) to support testing and benchmarking.

Use in LLM Translation Tools Benchmarking

• Complexity: Offers a complex codebase that presents realistic challenges for LLMs, unlike simplistic examples.
• Variety of Features: Covers a wide range of COBOL and mainframe features, including VSAM files, DB2 database interactions, CICS transactions, and error handling mechanisms.
• Benchmark Creation: Serves as a foundation for creating benchmark translations and training pairs for developing and fine-tuning LLM translation tools.

Development Status

Currently implemented components:

• ✅ Core Batch Processing Programs
• ✅ Online Inquiry System
• ✅ Utility Programs
• ✅ Reporting System
• ✅ Test Components
• ✅ System Monitoring Tools
• ✅ Security Framework

Documentation

Comprehensive documentation is provided to facilitate understanding and translation:

• System Architecture Document (SAD)
• Data Dictionary
• Operations Guide
• Test Data Specifications

Technical Standards

• COBOL Standards: Enterprise COBOL for z/OS compliance.
• Mainframe Patterns: Implements standard file handling, batch processing, and error handling patterns.
• Database Integration: Follows DB2 for z/OS SQL standards.
• Online Processing: Incorporates CICS transaction processing standards.
• Security: Adheres to mainframe security best practices.

Quality Standards

• Production-Grade Code: Written to production standards suitable for z/OS deployment.
• Error Handling: Includes comprehensive error handling and recovery procedures.
• Documentation: Provides detailed documentation for all components.
• Testing: Contains test programs and data for validation purposes.

Future Plans

• LLM Translation Training Pairs: Create benchmark translations to modern languages like Java or C#.
• Fine-Tuning LLMs: Use the project to enhance the capabilities of LLM translation tools in handling complex legacy codebases.
• Community Contribution: Encourage collaboration within the COBOL modernization community to improve and expand the benchmark.

License

[Appropriate License]

Contributing

Contributions are welcome, especially from those interested in COBOL modernization and LLM development. Please see the Contributing Guidelines for more information.