# Fody/PropertyChanged

Injects INotifyPropertyChanged code into properties at compile time

Repository: https://github.com/Fody/PropertyChanged
Canonical: https://ross.abutalabs.com/products/propertychanged
Language: C#
License: MIT
License Family: permissive
Last push: 2026-07-09T09:41:22+00:00

## Health v2 (maintenance only)
Score: 64/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 91, release rhythm 8, longevity 100
- inputs: {"age_days": 5170, "days_push": 55, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1967, forks 230 (observed 2026-08-28T04:05:59.949149+00:00)

## What it is
PropertyChanged.Fody is a Fody add-in that injects INotifyPropertyChanged notification code into property setters at compile time via IL weaving. It eliminates boilerplate in C# MVVM applications by automatically raising PropertyChanged events, including for dependent computed properties.

## Use cases
- remove inotifypropertychanged boilerplate from c# viewmodels
- automatically raise property changed events at compile time
- notify dependent computed properties when source properties change
- simplify mvvm viewmodel property change notifications
- weave property change code into existing c# classes

## When to choose
- you write WPF, UWP, or other .NET MVVM apps and want zero-boilerplate change notification
- you want dependent properties to automatically raise change events
- you prefer compile-time weaving over runtime reflection or base-class approaches

## When to avoid
- your project does not use the .NET/C# ecosystem
- you need runtime-configurable notification behavior rather than compile-time injection
- you are unwilling to adopt the Fody build pipeline or its patron licensing model

## Facets
- artifact type: library
- maturity: active
- function: build-tool, developer-tools
- domain: developer-tools, frontend, cross-platform
- platform: dotnet, cross-platform
- tags: fody, il-weaving, inotifypropertychanged, mvvm, compile-time-code-generation, csharp

## Member repositories
- Fody/PropertyChanged (main) score 64

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:05:59.949149+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T03:05:12.887882+00:00, confidence not recorded.
  - readme: https://github.com/Fody/PropertyChanged (fetched 2026-08-28T04:05:59.949149+00:00, sha adb10281086d)
- Data as of 2026-08-30T08:39:29.467469+00:00.