# Unexpected inconsistency in records

DevFeed: [Unexpected inconsistency in records](<https://devfeed.tech/articles/unexpected-inconsistency-in-records-30702.md>)

Original publisher: [Read original article](<https://codeblog.jonskeet.uk/2025/07/19/unexpected-inconsistency-in-records/>)

Author: jonskeet

Published: 2025-07-19T13:04:48Z

Content type: tutorial

Language: en

Sources: [Jon Skeet](<https://devfeed.tech/sources/jon-skeet.md>)

Topics: [C#](<https://devfeed.tech/topics/csharp.md>), [Code](<https://devfeed.tech/topics/code.md>), [bug](<https://devfeed.tech/topics/bug.md>)

Tags: [bug](<https://devfeed.tech/tags/bug.md>), [c-sharp](<https://devfeed.tech/tags/c-sharp.md>), [code](<https://devfeed.tech/tags/code.md>), [constructor](<https://devfeed.tech/tags/constructor.md>), [mutation](<https://devfeed.tech/tags/mutation.md>), [properties](<https://devfeed.tech/tags/properties.md>)

## AI overview

The article explains an inconsistency in C# records when nondestructive mutation is combined with derived data initialized from constructor parameters. The with-style operation uses a generated copy constructor, copying existing fields rather than recalculating derived values, which can leave the copied record internally inconsistent.

## Source excerpt

Unexpected inconsistency in records The other day, I was trying to figure out a bug in my code, and it turned out to be a misunderstanding on my part as to how C# records work. It's entirely possible that I'm the only one who expected them to work in the way that I did, but ... Continue reading Unexpected inconsistency in records ->