After writing to an external system, verify against it — don't trust your own write
After writing to an external system of record, don't trust your own write as fact — read back from the authoritative system and update your own copy to match what's actually there. The external system stays the real source of truth; your copy is a cache of it, verified after every write.
Pujan Motiwala ·
Context
A write to an external system of record can succeed on the wire but still not mean what you think — the request could be accepted and then rejected downstream, or applied differently than expected.
Decision
After posting, read back from the authoritative system and update your own copy to match what's actually there, not what you believe you sent.
Why
The external system is the real source of truth. Your own record of "what happened" is only correct once it's been checked against that system, not the moment the write request returns success.
Trade-off
Adds a read-back step, and a window where your copy is provisionally "pending confirmation" rather than settled — cheaper than the alternative of silently drifting from what the source of truth actually holds.
Seen in practice
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