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name: Neatoo description: This skill should be used when working with Neatoo domain models, ValidateBase, EntityBase, ValidateListBase, EntityListBase, partial properties, property change tracking, validation rules, business rules, aggregate roots, entities, value objects, lazy loading, LazyLoad, ILazyLoadFactory, or any .NET DDD domain model framework work. Also triggers for IsValid, IsSelfValid, IsSavable, IsModified, IsNew, IsDeleted, RuleManager, AddActionAsync, AddValidationAsync, AddAction, AddValidation, IsBusy, WaitForTasks, IsLoaded, IsLoading, and base class behavior. For factory attributes ([Factory], [Create], [Fetch], [Remote], [Service], [AuthorizeFactory]) see the RemoteFactory skill. version: 1.0.0

Neatoo Domain Models

Neatoo is a .NET framework for building domain models with automatic change tracking, validation, and persistence through Roslyn source generators. It provides base classes that map to DDD concepts with built-in support for client-server architectures.

Quick Start

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[Factory]
public partial class Product : EntityBase<Product>
{
    public Product(IEntityBaseServices<Product> services) : base(services) { }

    [Required]
    public partial string Name { get; set; }
    public partial decimal Price { get; set; }

    [Create] public void Create() { }
}

^{<a href='/src/samples/QuickStartSamples.cs#L11-L23' title='Snippet source file'>snippet source</a> | <a href='#snippet-skill-quickstart' title='Start of snippet'>anchor</a>}

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This generates a factory (IProductFactory) with a Create() method. Properties auto-track changes, trigger validation, and fire PropertyChanged.

Base Class Quick Reference

DDD Concept	Neatoo Base Class	Use When
Aggregate Root	EntityBase<T>	Root entity with full CRUD lifecycle
Entity	EntityBase<T>	Child entity within an aggregate
Value Object	ValidateBase<T>	Data with validation, no persistence lifecycle
Entity Collection	EntityListBase<I>	List of child entities (tracks deletions)
Validate Collection	ValidateListBase<I>	List of value objects (no deletion tracking)
Command	Static class with [Execute]	Server-side operation returning result
Read Model	ValidateBase<T> with [Fetch] only	Query result (no Insert/Update/Delete)

Key Properties

There is no IsDirty in Neatoo. Use IsModified / IsSelfModified.

Property	Type	Meaning
IsModified	bool	Has unsaved changes (this or children)
IsSelfModified	bool	This object (only) has changes
IsValid	bool	This object and all children pass validation
IsSelfValid	bool	This object (only) passes validation
IsSavable	bool	IsValid && IsModified && !IsBusy && !IsChild
IsNew	bool	Not yet persisted
IsDeleted	bool	Marked for deletion
RuleManager	IRuleManager	Access to validation rules

Core Patterns

Properties with Change Tracking

All Neatoo properties use partial properties. The source generator implements backing fields with automatic change tracking and validation triggering:

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public partial string Name { get; set; }
public partial decimal Price { get; set; }

^{<a href='/src/samples/QuickStartSamples.cs#L35-L38' title='Snippet source file'>snippet source</a> | <a href='#snippet-skill-properties-basic' title='Start of snippet'>anchor</a>}

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The generator creates property implementations that call Getter<T>() and Setter() internally.

Factory Methods

Neatoo entities use RemoteFactory for factory generation. See the /RemoteFactory skill for factory attributes ([Factory], [Create], [Fetch], [Insert], [Update], [Delete]), service injection ([Service]), remote execution ([Remote]), and authorization ([AuthorizeFactory]).

Save Routing (Neatoo State-Based)

When Save() is called, the factory routes based on Neatoo entity state:

• IsNew == true → [Insert] method
• IsNew == false && IsDeleted == false → [Update] method
• IsDeleted == true → [Delete] method

This routing is automatic based on entity state properties.

Aggregate Save Cascading

State cascades UP automatically; saves cascade DOWN manually — each parent's [Insert]/[Update] must call childFactory.SaveAsync() on its children. See references/entities.md → "Aggregate Save Cascading" for the full pattern, rules, and anti-patterns.

Validation

Add validation rules in the constructor using RuleManager or validation attributes:

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public SkillValidationExample(IEntityBaseServices<SkillValidationExample> services) : base(services)
{
    // Inline validation with lambda
    RuleManager.AddValidation(
        emp => string.IsNullOrEmpty(emp.Name) ? "Name is required" : "",
        e => e.Name);

    // Or use validation attributes on properties
    // [Required(ErrorMessage = "Name is required")]
    // public partial string Name { get; set; }
}

^{<a href='/src/samples/SkillValidationSamples.cs#L52-L64' title='Snippet source file'>snippet source</a> | <a href='#snippet-skill-validation' title='Start of snippet'>anchor</a>}

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RuleManager also provides AddAction, AddActionAsync, AddValidationAsync, and class-based rules. See references/validation.md → "Async Action Rules" for async side-effects (AddActionAsync) including LoadValue/deserialization behavior and exception propagation.

Check validation state with IsValid, IsSelfValid, and PropertyMessages.

Testing

Critical: Never mock Neatoo interfaces or classes. Use real factories and mock only external dependencies. Use [SuppressFactory] on test-only classes that inherit from Neatoo base classes. See references/testing.md for patterns and references/pitfalls.md for common mistakes.

Reference Documentation

Detailed documentation for each topic area:

• references/base-classes.md - Neatoo-to-DDD mapping, when to use each base
• references/properties.md - Partial properties, change tracking, calculated properties
• references/validation.md - RuleManager, attributes, async validation
• references/entities.md - EntityBase lifecycle, persistence, Save routing
• references/collections.md - EntityListBase, parent-child relationships, deletion tracking
• references/lazy-loading.md - LazyLoad<T>, ILazyLoadFactory, explicit async loading
• references/source-generation.md - What gets generated, Generated/ folder, [SuppressFactory]
• references/blazor.md - Blazor-specific binding and component patterns
• references/testing.md - No mocking Neatoo, integration test patterns
• references/pitfalls.md - Common mistakes and gotchas

RemoteFactory topics (see /RemoteFactory skill):

• Factory attributes, service injection, remote execution, authorization

Troubleshooting

See references/pitfalls.md for common issues. Key quick checks: class and properties must be partial, class needs [Factory] attribute, and IsSavable requires both IsValid and IsModified.