For most of software history, we knew what untrusted input looked like. Request parameters, form submissions, and user uploads are untrusted. External data requires validation before we use it. Application security revolves around maintaining this separation. User input provides values to the application. It must not redefine what the application is allowed to do. SQL, command, and template injections are dangerous for this exact reason. They break the assumption of separation and allow data to influence execution....

Most backend systems eventually grow a hidden workflow engine. It rarely starts that way. It usually begins with a simple cron job that wakes up every ten minutes, queries the database for pending records, processes them, and updates a status column. It seems simple enough, until production happens. A downstream API times out. A worker crashes halfway through processing. A deployment abruptly kills the process. A customer asks why their job is stuck....

For decades, software engineering had a fairly predictable constraint. Writing software was expensive. Every feature required engineers, every system required implementation, and every new capability required time, effort, and people. That constraint shaped how we built software. Today, it is disappearing. AI can generate code faster than most teams can review it, and that changes something fundamental about the job. The Old Bottleneck For most of software history, engineering organizations optimized for output....