Avoid fetching external/view state inside event upcasters

takeaway 2 connections

Upcasters that rely on view models break when those views are refreshed or rebuilt; keep upcasting logic pure with respect to data in the event itself.

type

warning

takeaway Avoid fetching external/view state inside event upcasters

about

Event Versioning / Upcasting concept

Rule about implementing event upcasters safely.

takeaway Avoid fetching external/view state inside event upcasters

from_talk

Applying CQRS & Event Sourcing on Rails applications talk

Warning raised in the event versioning section.

Provenance

Created in: Applying CQRS & Event Sourcing on Rails applications — An... 2026-04-17 16:18