System.Xml.XDocument by: Microsoft

Provides the classes for Language-Integrated Query (LINQ) to Extensible Markup Language (XML). LINQ to XML is an in-memory XML programming interface that enables you to modify XML documents efficiently and easily. Commonly Used Types: System.Xml.Linq.XElement System.Xml.Linq.XAttribute System.Xml.Linq.XDocument System.Xml.Linq.XText System.Xml.Linq.XNode System.Xml.Linq.XContainer System.Xml.Linq.XComment System.Xml.Linq.XObject System.Xml.Linq.XProcessingInstruction System.Xml.Linq.XDocumentType When using NuGet 3.x this package requires at least version 3.4.

System.Xml.XmlDocument by: Microsoft

Provides an older in-memory Extensible Markup Language (XML) programming interface that enables you to modify XML documents. Developers should prefer the classes in the System.Xml.XDocument package. Commonly Used Types: System.Xml.XmlNode System.Xml.XmlElement System.Xml.XmlAttribute System.Xml.XmlDocument System.Xml.XmlDeclaration System.Xml.XmlText System.Xml.XmlComment System.Xml.XmlNodeList System.Xml.XmlWhitespace System.Xml.XmlCDataSection When using NuGet 3.x this package requires at least version 3.4.

System.Xml.XmlSerializer by: Microsoft

Provides classes for serializing objects to the Extensible Markup Language (XML) and deserializing XML data to objects. Commonly Used Types: System.Xml.Serialization.IXmlSerializable System.Xml.Serialization.XmlSerializer System.Xml.Serialization.XmlIgnoreAttribute System.Xml.Serialization.XmlElementAttribute System.Xml.Serialization.XmlAttributeAttribute System.Xml.Serialization.XmlArrayAttribute System.Xml.Serialization.XmlRootAttribute System.Xml.Serialization.XmlArrayItemAttribute System.Xml.Serialization.XmlTypeAttribute System.Xml.Serialization.XmlEnumAttribute When using NuGet 3.x this package requires at least version 3.4.

System.Xml.XPath by: Microsoft

Provides the classes that define a cursor model for navigating and editing Extensible Markup Language (XML) information items as instances of the XQuery 1.0 and XPath 2.0 Data Model. Commonly Used Types: System.Xml.XPath.XPathNavigator System.Xml.XPath.IXPathNavigable System.Xml.XPath.XPathNodeType System.Xml.XPath.XPathNodeIterator System.Xml.XPath.XPathExpression System.Xml.XPath.XPathResultType System.Xml.XPath.XPathException System.Xml.XPath.XPathDocument System.Xml.XPath.XPathItem System.Xml.XPath.XPathNamespaceScope When using NuGet 3.x this package requires at least version 3.4.

System.Xml.XPath.XDocument by: Microsoft

Provides extension methods that add System.Xml.XPath support to the System.Xml.XDocument package. Commonly Used Types: System.Xml.XPath.Extensions System.Xml.XPath.XDocumentExtensions When using NuGet 3.x this package requires at least version 3.4.

System.Xml.XPath.XmlDocument by: Microsoft

System.Xml.XPath.XmlDocument

Utf8Json by: neuecc

Definitely Fastest and Zero Allocation JSON Serializer for C#(NET, .NET Core, Unity, Xamarin).