Core · One system owns each piece of data. Everything else copies.
Source of truth
When the CRM, a Google Sheet and an email tool all edit the same customer and sync both ways, they drift. Nobody knows which phone number is right, and sync loops quietly burn tasks.
Try this
Run each experiment in the simulator above, then tick it off.
Key ideas
Name an owner per field
Phone and plan live in the CRM. Open rates live in the email tool. Write it down before you build.
Sync flows one way
Owner to copies. A copy never writes back directly; it asks the owner to change.
Beware the loop
Two-way syncs fire on their own updates: A updates B, B's “updated” trigger updates A, and round it goes. Every hop is a task.
In your Pabbly workflows
Sketch the client's data map first: which app owns contacts, deals, invoices. Make every workflow flow from the owner outward. If a two-way sync is unavoidable, filter out updates made by your own integration user, or compare values and stop when nothing actually changed.
Check yourself
0/2Get every question right to mark this lab done. Wrong answers let you try again.
Q1. A sheet and a CRM sync both ways. Two staff edit the same contact a second apart. Likely outcome?
Each sync overwrites with whatever arrives last, and arrival order differs per system. Last write wins, somewhere else first.
Q2. Best fix for an update loop between two apps?
Delays only slow the loop down. Ownership or a self-update filter actually breaks it.
Lab complete
Marked done on this device. On to the next one.
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