The Valley of Webhooks

Developers repeatedly build complex webhook synchronization systems to maintain local copies of data from third-party providers (like Stripe or identity services), only to discover that webhooks' "at-least-once" delivery guarantee with no ordering creates fundamental problems: missing notifications go undetected, duplicates must be deduped, and race conditions require reconciliation jobs that nightly re-derive the entire dataset from scratch. The core issue is that webhooks are inherently unreliable notifications rather than ordered logs, forcing every consumer to independently reconstruct the provider's original data history with their own bugs, despite that history already existing in the provider's system.