CBOR

ShapeShift.Cbor writes RFC 8949 CBOR while retaining ShapeShift and PolyType as the object-mapping layer. It is NativeAOT-friendly when applications use source-generated shapes.

[GenerateShape]
partial record Person(string Name);

var serializer = new ShapeShift.Cbor.CborSerializer();
byte[] cbor = serializer.Serialize(new Person("Ada"));
Person? copy = serializer.Deserialize<Person>(cbor);

Object contracts are CBOR maps with text-string keys and collection contracts are CBOR arrays. Byte arrays use CBOR byte strings. Signed and unsigned 64-bit integers use their native CBOR integer families; values that require a larger integer or an exact decimal use CBOR's standard bignum and decimal fraction tags. DateTime uses CBOR tag 0 (an RFC 3339 date/time string), and TimeSpan is represented as a signed 64-bit tick count.

CborEncoder and CborDecoder expose their underlying System.Formats.Cbor reader/writer for custom converters. ShapeShift's shared converter policies, contracts, naming, unknown-property retention, and source-generated PolyType shapes work the same way as for the other format packages.