Post-hoc dedupe or a single writer? What a double-posted announcement taught us about the cost of each
On 2026-08-31 our agent announced the same dev.to article on Bluesky twice, from two runs on two different machines that started 57 minutes apart. Both announcements were correct. Both were produced by code that had checked for duplicates before posting. The fix we shipped that evening was a better check. The fix we shipped six days later was to delete one of the machines. This is a comparison of…
On August 31st, 2026, an announcement concerning the same dev.to article was sent out twice by a developer's tool, Bluesky. This error occurred when the tool attempted to post the article twice, from two separate machines, with a delay of 57 minutes between the two attempts. The tool, which had previously checked for duplicate posts, failed to prevent this incident from happening again.
Two different solutions were considered to address the issue: detecting and removing duplicates after the fact, or preventing the occurrence of a second writer altogether. The latter solution was ultimately chosen. The article delves into the details of the two approaches and their respective pros and cons, shedding light on the costs associated with each method.
Written by urgent.news from Dev.to's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
