👁 Image
Metalama.Patterns.Observability 2026.1.18

👁 Metalama Logo

About

The Metalama.Patterns.Observability contains an aspect that implements the Observer pattern, i.e. the INotifyPropertyChanged interface.

Key Features

• Supports automatic properties, explicit properties (including field-backed properties).
• Supports child objects, i.e. properties like string FullName => $"{this.Model.FirstName} {this.Model.LastName}".
• Idiomatic. Does not require you to change your coding patterns (unlike the MVVM community toolkit).
• Safe. Reports warnings when a property dependency is not understood.

Main Types

The primary types in this package are:

• ObservableAttribute is a type-level aspect that implements the Observer pattern and the INotifyPropertyChanged interface.
• NotObservableAttribute is an attribute that waives a property from the ObservableAttribute aspect.
• ConstantAttribute is an attribute that represents that a method is safed for use from a property made observable by the ObservableAttribute aspect.
• SuppressObservabilityWarningsAttribute is an attribute that suppresses all warnings reported by the ObservableAttribute aspect in the target property.
• ObservabilityExtensions.ConfigureObservability is a fabric extension method that allows to configure the ObservableAttribute aspect.

Additional Documentation

• Conceptual documentation
• API documentation

Related Packages

• Metalama.Patterns.Immutability implements the immutability concept used by the current package to decide which method calls are supported in property getters.