The Last Invoice

For twenty-five years, software gave you better tools. Now it's doing the work.

Every year, businesses spend trillions of dollars paying each other through a system that hasn't fundamentally changed in decades. Paper invoices. Manual data entry. Three levels of approval for a $47 order of office supplies. Checks. Actual paper checks, in 2026.

That system is about to break.

AI agents, software that doesn't just assist but actually acts, are replacing the back office one invoice at a time. Not in some distant future. Right now. BILL reported a 533% increase in AI-processed transactions. Klarna replaced 700 customer service agents with AI, then quietly started rehiring when quality collapsed. Mastercard and Visa are building payment rails designed for a world where software, not people, initiates transactions.

The Last Invoice is the insider's guide to this transformation, written by a payments industry veteran who has spent fifteen-plus years building the systems that are now making human processors obsolete. Chris Wyatt traces the arc from SaaS to "service as software," explains why B2B payments is the proving ground for the broader AI revolution, and delivers a practical playbook for CFOs navigating the biggest shift in corporate finance in a generation.

This book will show you:

• Why the $500 billion software market is about to collide with the vastly larger services market
• How AI agents process invoices in seconds that take humans days
• What Klarna's hire-fire-rehire cycle teaches every company about AI deployment
• Why your BPO provider has a financial incentive to slow-walk automation
• The 90-day, one-year, and three-year roadmap for transforming your finance operation
• Where this thesis might be wrong, and what breaks at scale
Written for CFOs, finance leaders, founders, and anyone who processes, receives, or manages payments. No jargon. No hype. Just the clearest picture of what's coming and how to lead through it.

"The age of human-centered financial processing is ending. The age of human-guided intelligent operations has begun."