A few months ago we started getting reports of stories appearing multiple times in the For You feed on Medium mobile apps. See for instance the screenshot below, in which the “Breaking News: Stuff…

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Medium Engineering

Fixing duplicate stories in Medium's For You feed by making changes to the caching logic and concurrency issues.

Fixing duplicate stories in Medium’s For You feed

Change #1: Fix premature cancellation of cache store operations

Change #2: Ensure cached feed instances are reused when available