Morph

A lightweight, MIT-licensed object-to-object mapper for .NET. API-compatible with the core of AutoMapper v14.

Why

AutoMapper moved to a commercial license in 2024. Morph mirrors the API surface most consumers actually use, so existing codebases can swap it in with minimal changes — in many cases, a single using statement change.

Install

dotnet add package Morph

Target frameworks: netstandard2.0 (broad compatibility — .NET Framework 4.7.2+, .NET Core 2.0+, Xamarin, Unity) and net10.0.

Quick start

using Morph;

var config = new MapperConfiguration(cfg =>
{
    cfg.CreateMap<Source, Destination>()
       .ForMember(d => d.FullName, o => o.MapFrom(s => s.FirstName + " " + s.LastName));
});

var mapper = config.CreateMapper();
var dest = mapper.Map<Destination>(source);

What's in scope

• Profile + CreateMap
• ForMember + MapFrom (lambda, expression, member access)
• ReverseMap
• ConstructUsing
• ConvertUsing<T> / ITypeConverter<,>
• Map(source, existingDestination) overload
• Multi-profile registration
• Property-by-name convention mapping
• Primitive coercion (decimal, DateTime, etc.)
• Collections (List, empty, nested)
• Runtime-type dispatch
• AssertConfigurationIsValid

See docs/api-surface.md for the authoritative feature matrix.

What's not in this release

• ProjectTo / EF integration
• Inheritance maps
• Flattening
• Open generics
• Custom naming conventions
• ForCtorParam

These are on the roadmap. If your code relies on them, Morph v0.1 is not yet a drop-in.

Security

Morph is hardened against CVE-2026-32933 (uncontrolled recursion on self-referential graphs causing StackOverflowException). Morph enforces a configurable MaxDepth (default 32) and throws a catchable AutoMapperMappingException instead.

var config = new MapperConfiguration(cfg =>
{
    cfg.MaxDepth = 64; // default 32
    cfg.CreateMap<Node, NodeDto>();
});

Compatibility verification

Morph ships with a dual-compilation compat harness under validation/compat/ that runs the same consumer code twice — once against Morph, once against AutoMapper 14.0.0 from NuGet. Both legs currently green on 21 scenarios covering the features listed above. See validation/compat/README.md.

Status

v0.1.0-alpha — alpha release. Core API-compatible subset of AutoMapper v14. Expect bugs; file issues at github.com/nexus-cw/Morph/issues.

License

MIT. See LICENSE.