Same Data, Two Windows
Around 2 PM one day, the Dream Team's bots sent an unusual signal. A Claude Code bot running on Windows and another bot running on Mac mini tried to access the same spreadsheet cell simultaneously. The moment they collided, the data record became a mess.
At first, we thought it was a network issue. But checking the logs revealed a simpler yet more critical problem. Both bots tried to modify the same row at the same time.
The Hidden Trap in Automation: Concurrency
This is the easiest thing for non-developers to overlook when building bots. When small teams automate small tasks, they only think about processing things sequentially, one by one. But what happens when you run two devices simultaneously?
The Problem Scenario:
• Bot A on Windows device: Starts updating buyer list at 10:15 AM
• Bot B on Mac mini: Starts validating the same list at 10:15 AM
• Result: Data corruption, missing records, rework required
The Solution: Timestamp-Based 'Priority Check'
We added simple logic to Claude Code. Each bot checks the last modified time before accessing a cell.
1. Record current time (HH:MM:SS)
2. Compare with last modified time
3. If time difference is within 3 seconds, wait
4. Retry after 5 seconds
With just this simple "wait logic," we reduced conflicts by 95%.
The Big Lesson a Small Team Learned
After this incident, we established this policy.
When there are 2 or more automation bots, always define a clear order.
• **Primary Device (Windows)**: Tasks from 9 AM to noon
• **Secondary Device (Mac mini)**: Tasks from 2 PM to 5 PM
• **Overlapping Time**: Data validation work only
This "time slot division" approach actually improved efficiency. Each bot focused only on its own time slot, and error handling logic became much simpler.
The Next Stage of AI Automation
A question non-developers often ask when starting automation is.
"Can I run multiple bots simultaneously?"
Technically, the answer is "yes." But operationally, it's "be careful." Multitasking looks efficient, but sequential processing might actually be more stable.
Especially when small teams touch shared documents like Google Sheets or Excel. This experience taught us an important lesson.
"Reliability comes before speed in automation."
Next time, we plan to implement a more sophisticated "queue system." Whether Claude Code can achieve this is still under experimentation.