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Modernizing IBM i rarely means replacing it. This guide collects the AS400Decoded articles on connecting IBM i to modern tools and architectures, starting with strategy and moving through APIs, open source, DevOps, cloud, and AI.
Modernization Strategy
- IBM i Modernization Basics
- IBM i Application Modernisation Roadmap in 2026: Strategies from API Wrapping to Full Rewrite and How to Choose
- IBM i Modernization: From Legacy AS400 Systems to Modern Enterprise Architecture
- Strangler Fig Pattern for IBM i Application Modernization: Decomposing Monolithic RPG, API Gateway Routing, Incremental Migration, and Coexistence Strategies in 2026
Modern RPG
- Free-format RPG: A practical guide for intermediate developers
- AI-Assisted RPG Modernization on IBM i in 2026: CVTRPGSRC, IBM Merlin Converter, LLM Code Explanation, Automated Refactoring, and AI-Generated RPG Tests
REST APIs, HTTP, and JSON
- IBM i REST APIs and HTTP Client Integration Explained
- Modern integrations on IBM i: calling REST APIs and working with JSON
- Calling REST APIs from IBM i RPG in 2026: HTTPAPI by Scott Klement, HTTP GET and POST, JSON Parsing with YAJL, and OAuth 2.0
- OAuth 2.0 and JWT Authentication from IBM i: Client Credentials Flow, Bearer Token Management, and Calling OAuth-Protected REST APIs from ILE RPG in 2026
- IBM i JSON and XML Processing for Modern Applications
Open Source on IBM i: PASE, Node.js, and Python
- IBM i PASE Deep Dive: AIX Binary Compatibility, PASE vs QShell, Environment Variables, Process Management, and ILE Integration in 2026
- IBM i and Node.js in 2026: Running Node.js in PASE, Accessing DB2 for i, and Building REST APIs on IBM i
- Building REST APIs on IBM i: Node.js in PASE, IAS REST, and connecting modern front ends to your RPG business logic
- Building a REST API Server on IBM i with Node.js and Express: DB2 Access via ODBC, Routing, JSON Responses, Middleware, and Running as a Batch Job in 2026
- Python on IBM i in 2026: Running Python in PASE, Accessing DB2 for i, Calling IBM i Programs with itoolkit, and AI Integration
Git, VS Code, Testing, and DevOps
- Source control for IBM i: managing your RPG and CL source with Git and RDi
- IBM Merlin and VS Code for IBM i Development in 2026: Modern IDE Setup, RPG and CL Editing, Git Integration, and the IBM i Developer Workstation
- IBM i in a DevOps Pipeline: Git, Bob, Automated Builds, and CI/CD for RPG in 2026
- RPG Unit Testing with RPGUnit in 2026: Writing Test Cases for ILE RPG Service Programs, Test Suites, and CI Integration
- IBM i Application Maintenance and Change Management
- IBM i Application Design Patterns for Teams
Messaging, Events, and Email
- IBM MQ Messaging from IBM i: Queue Managers, Channels, MQPUT, MQGET, Triggering, Dead Letter Queues, and RPG Integration in 2026
- IBM i and Apache Kafka in 2026: Journal-Based CDC to Kafka Topics, PASE Producers, and Event-Driven IBM i Integration
- IBM i Outbound Email in 2026: SNDDST, SMTP Configuration, SNDSMTPEMM, HTML Email from RPG, and PASE Sendmail
Cloud Integration
- IBM i and the cloud: modernisation strategies, hybrid architectures, and what staying on IBM i actually means in 2026
- Connecting IBM i to the Cloud: Azure, AWS, Power Virtual Server, and Hybrid Integration Patterns That Actually Work
- IBM i Integration with Microsoft Azure in 2026: Azure Event Hubs, Blob Storage, Service Bus, and Azure SQL from PASE
AI for IBM i
- AI for IBM i in 2026: Calling AI APIs from RPG and SQL, Integrating watsonx, and What AI Can Realistically Do for IBM i Modernisation
- IBM watsonx on Power for IBM i: AI Inference Near Your Data, Granite Models, RPG and Python Integration in 2026
- AI-Assisted Legacy Code Documentation on IBM i in 2026: Using LLMs to Document RPG Programs, Extract Business Rules, and Build a Knowledge Base
- AI-Driven Anomaly Detection on IBM i Operational Data: DB2 Statistical Baselines, Python in PASE, Isolation Forest, and Automated Alerting in 2026
- Vector Search and Embeddings on IBM i in 2026: Storing Vectors in DB2 for i, Cosine Similarity in SQL, and Semantic Search over IBM i Data
Modern User Interfaces
Planned Topics
These topics are on the writing plan for this guide:
- Setting up a CI/CD pipeline for RPG step by step
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