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What Is IBM i, Really? Understanding the Platform Before You Touch a Line of RPG
Somewhere behind the scenes of a bank transfer, an insurance claim, or a retail order confirmation, there's a good chance IBM i is doing the work. It's easy to dismiss the platform as legacy technology because of where it came from — the…
Jobs, Queues, and Subsystems: How IBM i Actually Runs Your Code
Every program that runs on IBM i — whether it's a user signing in interactively, a batch report kicked off overnight, or a system task doing internal housekeeping — runs inside something called a job. Understanding the job model is one of…
Source Physical Files vs. the IFS: Two Ways IBM i Stores Your Code
IBM i developers today work with source code in two fundamentally different storage models, and knowing both — along with why the industry is steadily shifting from one to the other — is essential context before writing any RPG.
PDM and SEU: The Green-Screen Tools That Still Run Countless Shops
Long before Eclipse-based IDEs arrived on IBM i, there was PDM and SEU — and despite decades of tooling advances since, both are still in daily use across a significant share of IBM i shops today. Understanding them isn't a nostalgia…
Setting Up RDi: Bringing Modern IDE Tooling to IBM i Development
Rational Developer for i, known almost universally as RDi, is the modern counterpart to PDM and SEU — an Eclipse-based IDE that brings syntax checking, code outline views, integrated source control, and a proper debugger to IBM i…
The CL Commands Every RPG Developer Uses Every Day
Control Language, or CL, is how developers and operators actually operate IBM i — compiling objects, managing libraries, controlling jobs, and retrieving system information. Regardless of which development tools a shop uses, CL commands…
Programs, Modules, and Service Programs: Making Sense of the ILE Object Model
The Integrated Language Environment, or ILE, object model is the structural backbone of nearly everything built on IBM i today, and understanding how its core object types relate to one another is essential before writing modern ILE RPG.
DB2 for i: The Database That's Already Built Into Your Operating System
Ask a developer coming from another platform how their database relates to their operating system, and you'll typically hear about a separate installation, a server process to manage, and a connection string to configure. On IBM i, that…
How Real Enterprise IBM i Applications Are Actually Structured
Open an unfamiliar IBM i application for the first time, and it can feel overwhelming — dozens or hundreds of objects spread across multiple libraries, with no obvious starting point. But nearly every well-built enterprise IBM i…