ZodSharp

ZodSharp is a high-performance schema validation library for C#, ported from TypeScript Zod. It features zero-allocation validation, struct-based rules, fluent API, and source generator support for maximum performance.

Key Features

• Zero-allocation validation - Minimizes allocations using structs and Span<T>
• Struct-based rules - Validation rules implemented as structs to avoid GC
• Fluent API - Fluent and extensible API similar to original Zod
• Type-safe - Strong typing with advanced C# generics
• High performance - Sub-microsecond validation times, 10x faster than reflection-based validation
• Cross-platform - Works on .NET 9.0 and .NET Standard 2.1
• Source Generators - Compile-time validator generation with [ZodSchema] attribute
• DataAnnotations Support - Automatic validation from [Required], [StringLength], [Range], etc.

Installation

NuGet Package Manager

Install-Package ZodSharp

.NET CLI

dotnet add package ZodSharp

PackageReference

<PackageReference Include="ZodSharp" Version="1.0.0" />

Usage Examples

Basic Validation

using ZodSharp;
using ZodSharp.Core;

// String validation
var nameSchema = Z.String().Min(3).Max(50);
var result = nameSchema.Validate("John");
if (result.IsSuccess)
{
    Console.WriteLine($"Valid name: {result.Value}");
}

// Number validation
var ageSchema = Z.Number().Min(0).Max(120).Int();
var ageResult = ageSchema.Validate(25.0);

// Additional number validations
var positiveSchema = Z.Number().Positive();
var negativeSchema = Z.Number().Negative();
var multipleOfSchema = Z.Number().MultipleOf(10); // Must be multiple of 10
var finiteSchema = Z.Number().Finite(); // Not Infinity
var safeSchema = Z.Number().Safe(); // Safe integer

// Email validation
var emailSchema = Z.String().Email();
var emailResult = emailSchema.Validate("user@example.com");

// URL validation
var urlSchema = Z.String().Url();
var urlResult = urlSchema.Validate("https://example.com");

// UUID validation
var uuidSchema = Z.String().Uuid();
var uuidResult = uuidSchema.Validate("550e8400-e29b-41d4-a716-446655440000");

// String transformations
var trimmedSchema = Z.String().Trim();
var upperSchema = Z.String().ToUpper();
var lowerSchema = Z.String().ToLower();

// String prefixes and suffixes
var prefixSchema = Z.String().StartsWith("https://");
var suffixSchema = Z.String().EndsWith(".com");

// Exact length
var exactLengthSchema = Z.String().Length(10);

Object Validation

var userSchema = Z.Object()
    .Field("name", Z.String().Min(1))
    .Field("age", Z.Number().Min(0).Max(120))
    .Field("email", Z.String().Email())
    .Build();

var userData = new Dictionary<string, object?>
{
    { "name", "John Doe" },
    { "age", 30.0 },
    { "email", "john@example.com" }
};

var result = userSchema.Validate(userData);
if (result.IsSuccess)
{
    var validatedUser = result.Value;
    // Use validatedUser...
}

Array Validation

var numbersSchema = Z.Array(Z.Number()).Min(1).Max(10);
var result = numbersSchema.Validate(new[] { 1.0, 2.0, 3.0 });

// Exact length
var exactLengthSchema = Z.Array(Z.String()).Length(5);

// Non-empty array
var nonEmptySchema = Z.Array(Z.String()).NonEmpty();

Optional Fields

var optionalSchema = Z.Optional(Z.String());
var result1 = optionalSchema.Validate(null); // Success
var result2 = optionalSchema.Validate("value"); // Success

Error Handling

try
{
    var value = nameSchema.Parse("AB"); // Too short - throws
}
catch (ZodException ex)
{
    Console.WriteLine($"Validation failed: {ex.Message}");
    foreach (var error in ex.Errors)
    {
        Console.WriteLine($"  - {string.Join(".", error.Path)}: {error.Message}");
    }
}

// Or use SafeParse for non-throwing validation
var result = nameSchema.SafeParse("AB");
if (!result.IsSuccess)
{
    foreach (var error in result.Errors)
    {
        Console.WriteLine($"Error: {error.Message}");
    }
}

Performance

ZodSharp is designed for maximum performance with zero-allocation validation and struct-based rules. Here's what makes it fast:

Performance Characteristics

Typical validation times (measured on .NET 9.0, Release mode):

• Simple string validation: ~50-100 ns per validation
• Number validation: ~30-80 ns per validation
• Small arrays (10 items): ~500-800 ns per validation
• Medium objects (6 fields): ~1-2 μs per validation
• Complex objects (13 fields with nesting): ~3-5 μs per validation

Memory efficiency:

• Zero allocations for simple validations (strings, numbers, booleans)
• Minimal allocations for arrays and objects (only for error collections)
• Struct-based rules avoid GC pressure
• No reflection overhead in hot paths

Performance Optimizations

ZodSharp implements several optimizations for maximum performance:

1. Zero-allocation Validation

• Validation rules implemented as struct to avoid allocations
• Use of Span<T> and ReadOnlySpan<T> when appropriate
• Object pooling for reusable schemas

2. Struct-based Rules

All validation rules are structs:

public readonly struct MinLengthRule : IValidationRule<string>
{
    // Zero allocation validation
}

3. Compiled Validators

Use expression trees to compile validators at runtime for maximum speed:

using ZodSharp.Expressions;

var compiled = CompiledValidator.Compile(schema);
var result = compiled(value); // Ultra-fast validation

4. Fluent API

Fluent API that allows schema composition:

var schema = Z.String()
    .Min(3)
    .Max(50)
    .Email()
    .Describe("User email address");

Performance Benchmarks

We maintain comprehensive performance tests in the performance/ folder. Run them yourself:

# Run all performance benchmarks
dotnet run --project performance/performance.csproj -c Release

# Run specific test suites
dotnet run --project performance/performance.csproj -c Release --filter "*MemoryPerformanceTests*"

Key performance highlights:

• 10x faster than reflection-based validation libraries
• Zero allocations for primitive validations
• Sub-microsecond validation for simple types
• Minimal GC pressure with struct-based architecture
• Scalable performance even with complex nested schemas

See the performance README for detailed benchmark results and optimization tips.

Architecture

ZodSharp/
├── Core/              # Base interfaces and classes
│   ├── IZodSchema.cs
│   ├── ZodType.cs
│   ├── ValidationResult.cs
│   └── ValidationError.cs
├── Schemas/           # Schema implementations
│   ├── ZodString.cs
│   ├── ZodNumber.cs
│   ├── ZodObject.cs
│   └── ...
├── Rules/             # Validation rules (structs)
│   ├── MinLengthRule.cs
│   ├── EmailRule.cs
│   └── ...
└── Optimizations/     # Optimization helpers
    └── ZeroAllocationHelpers.cs

Advanced Features

Transforms

Transform values during validation:

var schema = Z.String().Transform(s => s.ToUpper());
var result = schema.Validate("hello"); // "HELLO"

Refinements

Add custom validations:

var schema = Z.Number().Refine(n => n % 2 == 0, "Must be even");
var result = schema.Validate(4); // Success

Lazy Evaluation

Create recursive and circular schemas:

var categorySchema = Z.Lazy<Dictionary<string, object?>>(() => 
    Z.Object()
        .Field("name", Z.String())
        .Field("subcategories", Z.Array(categorySchema))
        .Build()
);

Discriminated Unions

Optimized unions with discriminator:

var union = Z.DiscriminatedUnion("type")
    .Option("user", userSchema)
    .Option("admin", adminSchema)
    .Build();

Default Values

Default values when input is null:

var schema = Z.String().Default("unknown");
var result = schema.Validate(null); // "unknown"

JSON Integration

Integrated JSON validation with Newtonsoft.Json:

using ZodSharp.Json;

// Deserialize and validate from string
var result = schema.DeserializeAndValidate(jsonString);

// Deserialize and validate from stream (async)
var result2 = await schema.DeserializeAndValidateAsync(jsonStream);

// Deserialize and validate from JToken
var result3 = schema.DeserializeAndValidate(jToken);

// Create JsonConverter with validation
var converter = schema.CreateValidatingConverter();

Compiled Validators

Compiled validators for maximum performance:

using ZodSharp.Expressions;

var compiled = CompiledValidator.Compile(schema);
var result = compiled(value); // Ultra-fast validation

Schema Caching

Intelligent schema caching:

using ZodSharp.Core;

var schema = SchemaCache.GetOrCreate("user", () => 
    Z.Object().Field("name", Z.String()).Build()
);

Source Generators

Generate zero-allocation validators at compile time:

using System.ComponentModel.DataAnnotations;
using ZodSharp.SourceGenerators;

[ZodSchema]
public class User
{
    [Required]
    [StringLength(50, MinimumLength = 3)]
    public string Name { get; set; } = string.Empty;

    [Required]
    [Range(0, 120)]
    public int Age { get; set; }

    [EmailAddress]
    public string? Email { get; set; }
}

// Auto-generated validator
var result = UserSchema.Validate(user);
var validated = UserSchema.Parse(user); // Throws on failure

// Composition methods
var refined = UserSchema.Refine(user, u => u.Age >= 18, "Must be adult");
var combined = UserSchema.And(user, u => u.Name.Length > 5, "Name too short");

Features:

• Automatic validation from DataAnnotations attributes
• Zero-reflection, zero-allocation validators
• Composition methods (.And(), .Or(), .Refine())
• Supports classes, structs, and records

Span Validation

Zero-allocation string validation using spans:

var schema = Z.String().Min(3).Max(50).Email();
var span = "user@example.com".AsSpan();
var result = schema.ValidateSpan(span);

License

MIT License - see the LICENSE file for details.

Contributing

Contributions are welcome! Please open an issue or pull request.

Acknowledgments

• Zod