IBM i Security Best Practices for Developers

Learning Objective

By the end of this lesson, you will be able to apply a set of practical security habits to everyday IBM i development work, drawn from across this batch.

Simple Explanation

A handful of habits make the difference between security that stays manageable over time and security that quietly erodes, drawn from the concepts covered across this batch:

• Grant least privilege. Give a user or program exactly the authority it needs, no more, using the object, group profile, and authorization list concepts covered earlier in this batch, rather than defaulting to broad access.
• Do not overuse *ALLOBJ. As covered earlier in this batch, reaching for a special authority to quickly make an authority failure disappear bypasses the deliberate authority design entirely.
• Avoid hardcoded privileged assumptions. Do not write program logic that assumes it will always run with elevated or adopted authority; be explicit about which parts of a design genuinely rely on that, as covered in the Adopted Authority lesson.
• Protect sensitive files with restrictive public authority. As covered in the Public and Private Authority lesson, default sensitive objects to something restrictive, and grant private authority deliberately, rather than leaving public authority generous.
• Avoid logging secrets. Passwords, and other sensitive values, should never end up in a job log, a spool file, or an integration log like the ones covered in the Modern IBM i / APIs / Integration lessons.
• Coordinate with security or admin teams. Authority decisions, especially anything involving special authorities or adopted authority, are rarely a developer's decision to make entirely alone.

Why It Matters

Every one of these habits addresses the same underlying risk: security that looks fine on the surface while a real gap or bad habit is quietly present underneath, the same pattern already familiar from the mistakes lessons covering ILE, integration, and advanced SQL work elsewhere in this course. Getting into these habits early is what keeps a system's security genuinely trustworthy as more developers, programs, and data accumulate over time.

Practical Example

Imagine a developer under time pressure grants their own user profile *ALLOBJ to get past a stubborn authority failure while testing a new report. The report works immediately, but the underlying authority gap, whatever specific file or library actually needed authority, is never actually identified or fixed for the next developer who hits the same wall, and the *ALLOBJ grant lingers indefinitely, exactly the kind of quietly accumulating risk this lesson is about. Taking the time to identify and grant the specific authority actually needed, using the concepts covered earlier in this batch, avoids this entirely.

This is a simplified, illustrative example rather than a specific real incident, but it reflects a genuinely common pressure every developer eventually faces.

Common Confusions

"Are these best practices only relevant to security specialists, not regular developers?" No. Every one of these habits applies directly to everyday development work: writing programs, granting test authority, and logging integration activity, not just formal security administration.

*"Is granting ALLOBJ ever an acceptable shortcut under time pressure?" It might feel like the fastest fix in the moment, but it trades a quick, narrow problem for a broad, lingering one. Identifying the specific authority actually needed is almost always the better choice, even under time pressure.

"Do these practices only matter for genuinely sensitive data, like payroll or financial records?" No. Good authority habits, least privilege, restrictive public authority defaults, and not logging secrets, are worth applying broadly, not reserved only for the most obviously sensitive systems.

Quick Recap

• Least privilege, avoiding *ALLOBJ overuse, avoiding hardcoded privileged assumptions, restrictive public authority defaults, avoiding logging secrets, and coordinating with security or admin teams are the core habits covered across this batch.
• These habits address the same underlying risk: security that looks fine on the surface while a real problem is quietly present underneath.
• Advanced topics such as the security audit journal, exit points and exit programs, row and column access control, and multi-factor authentication build on these fundamentals, and are covered next at an overview level, continuing where this lesson leaves off.

Try Asking the AI Tutor

Use the AI Tutor to ask follow-up questions about this lesson. For example, try asking:

• "Can you give me a short scenario where a developer is tempted to take a security shortcut, and ask me what the better approach would be?"
• "Which of these best practices would be easiest to accidentally skip under a tight deadline, and why?"