PCLCrypto by: Andrew Arnott

PCL Crypto provides a consistent, portable set of crypto APIs for .NET 4.5, Windows Store, Xamarin.iOS, Xamarin.Android. This makes it easier to create cross-platform .NET libraries and apps. Crypto functionality includes asymmetric and symmetric encryption and signatures, and key derivation. PCLCrypto calls into each native platform's crypto API for maximum performance. For RSA operations this produces a 2-100X improvement in performance on Android and iOS over using the standard RSACryptoServiceProvider API.

PCLStorage by: Daniel Plaisted

PCL Storage provides a consistent, portable set of local file IO APIs for .NET, Windows Phone, Windows Store, Xamarin.iOS, Xamarin.Android, and Silverlight. This makes it easier to create cross-platform .NET libraries and apps.

PdfiumViewer by: Pieter van Ginkel

PDF viewer based on the PDFium project.

PdfiumViewer.Native.x86.v8-xfa by: Pieter van Ginkel

Native 32-bit PDFium DLL with V8 and XFA support for usage with the PdfiumViewer project.

PdfPig by: UglyToad

Reads text content from PDF documents and supports document creation. Apache 2.0 licensed.

PDFsharp by: PDFsharp Team

PDFsharp is the Open Source library for creating and modifying PDF documents using .NET. It has an easy-to-use API that allows developers to generate or modify PDF files programmatically. PDFsharp can be used for various applications, including creating reports, invoices, and other types of documents. This package does not depend on Windows and can be used on any .NET compatible platform including Linux and macOS. See https://docs.pdfsharp.net for details.

PInvoke.BCrypt by: Andrew Arnott

P/Invoke methods for the Windows BCrypt.dll.

PInvoke.Kernel32 by: Andrew Arnott

P/Invoke methods for the Windows Kernel32.dll.

PInvoke.NCrypt by: Andrew Arnott

P/Invoke methods for the Windows NCrypt.dll.

PInvoke.Windows.Core by: Andrew Arnott

P/Invoke types for common Windows APIs.

PolyType by: Eirik Tsarpalis

Practical generic programming for C#

Portable.BouncyCastle by: Claire Novotny

BouncyCastle portable version with support for .NET 4, .NET Standard 2.0

Portable.BouncyCastle-Signed by: Mark Junker

BouncyCastle.Crypto is a cryptography API providing: -Generation and parsing of PKCS#12 files. -X.509: Generators and parsers for V1 and V3 certificates, V2 CRLs and attribute certificates. -PBE algorithms supported by PBEUtil: PBEwithMD2andDES-CBC, PBEwithMD2andRC2-CBC, PBEwithMD5andDES-CBC, PBEwithMD5andRC2-CBC, PBEwithSHA1andDES-CBC, PBEwithSHA1andRC2-CBC, PBEwithSHA-1and128bitRC4, PBEwithSHA-1and40bitRC4, PBEwithSHA-1and3-keyDESEDE-CBC, PBEwithSHA-1and2-keyDESEDE-CBC, PBEwithSHA-1and128bitRC2-CBC, PBEwithSHA-1and40bitRC2-CBC, PBEwithHmacSHA-1, PBEwithHmacSHA-224, PBEwithHmacSHA-256, PBEwithHmacRIPEMD128, PBEwithHmacRIPEMD160, and PBEwithHmacRIPEMD256. -Signature algorithms supported by SignerUtilities: MD2withRSA, MD4withRSA, MD5withRSA, RIPEMD128withRSA, RIPEMD160withRSA, RIPEMD256withRSA, SHA-1withRSA, SHA-224withRSA, SHA-256withRSAandMGF1, SHA-384withRSAandMGF1, SHA-512withRSAandMGF1, SHA-1withDSA, and SHA-1withECDSA. -Symmetric key algorithms: AES, Blowfish, Camellia, CAST5, CAST6, DESede, DES, GOST28147, HC-128, HC-256, IDEA, NaccacheStern, RC2, RC4, RC5-32, RC5-64, RC6, Rijndael, Serpent, Skipjack, TEA/XTEA, Twofish, and VMPC. -Symmetric key modes: CBC, CFB, CTS, GOFB, OFB, OpenPGPCFB, and SIC (or CTR). -Symmetric key paddings: ISO10126d2, ISO7816d4, PKCS#5/7, TBC, X.923, and Zero Byte. -Asymmetric key algorithms: RSA (with blinding), ElGamal, DSA, ECDSA. -Asymmetric key paddings/encodings: ISO9796d1, OAEP, and PKCS#1. -Digests: GOST3411, MD2, MD4, MD5, RIPEMD128, RIPEMD160, RIPEMD256, RIPEMD320, SHA-1, SHA-224, SHA-256, SHA-384, SHA-512, Tiger, and Whirlpool. -Signer mechanisms: DSA, ECDSA, ECGOST3410, GOST3410, ISO9796d2, PSS, RSA. -Key Agreement: Diffie-Hellman and EC-DH. -Macs: CBCBlockCipher, CFBBlockCipher, GOST28147, HMac, and ISO9797 Alg. 3. -PBE generators: PKCS#12, and PKCS#5 - schemes 1 and 2. -OpenPGP (RFC 2440) -Cryptographic Message Syntax (CMS, RFC 3852), including streaming API. -Online Certificate Status Protocol (OCSP, RFC 2560). -Time Stamp Protocol (TSP, RFC 3161). -TLS/SSL Client with support for client side authentication. Support for .NET 4, Windows Phone 8, Windows Phone App 8.1, Windows 8, Silverlight 5, MonoTouch, MonoAndroid

Portable.ConcurrentDictionary by: Stef Heyenrath

This is a .NET Standard 1.0, .NET 2.0, .NET 3.5, Silverlight 5.0 and Windows Phone Silverlight 8.0 & 8.1 backport from System.Collections.Concurrent.ConcurrentDictionary as defined in .NET Core

Portable.System.DateTimeOnly by: Oleg Rakhmatulin

DateOnly and TimeOnly types for .NET versions before 6.0

protobuf-net by: Marc Gravell

Provides simple access to fast and efficient "Protocol Buffers" serialization from .NET applications

protobuf-net.Core by: Marc Gravell

Provides simple access to fast and efficient "Protocol Buffers" serialization from .NET applications

PusherServer by: Pusher

Pusher .NET library for interacting with the HTTP API

QRCoder by: Raffael Herrmann, Shane Krueger

QRCoder is a simple library, written in C#.NET, which enables you to create QR codes.

Quartz by: Marko Lahma, Quartz.NET

Quartz Scheduling Framework for .NET