Browse free open source Libraries and projects for Linux and BSD below. Use the toggles on the left to filter open source Libraries by OS, license, language, programming language, and project status.

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  • 1
    Acl

    Acl

    A powerful server and network library, including coroutine

    The Acl (Advanced C/C++ Library) project a is powerful multi-platform network communication library and service framework, supporting LINUX, WIN32, Solaris, FreeBSD, MacOS, AndroidOS, iOS. Many applications written by Acl run on these devices with Linux, Windows, iPhone and Android and serve billions of users. There are some important modules in Acl project, including network communcation, server framework, application protocols, multiple coders, etc. The common protocols such as HTTP/SMTP/ICMP//MQTT/Redis/Memcached/Beanstalk/Handler Socket are implemented in Acl, and the codec library such as XML/JSON/MIME/BASE64/UUCODE/QPCODE/RFC2047/RFC1035, etc., are also included in Acl. Acl also provides a unified abstract interface for popular databases such as Mysql, Postgresql, Sqlite. Using Acl library users can write database applications more easily, quickly and safely.
    Downloads: 19 This Week
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  • 2
    Curl

    Curl

    Command line tool and library for transferring data with URLs

    Curl is a command line tool and library for transferring data specified with URL syntax. It supports HTTP, HTTPS, FTP, FTPS, GOPHER, TFTP, SCP, SFTP, SMB, TELNET, DICT, SSL certificates, cookies, user+password authentication, and so much more! Curl is used for many different things. It's used in command lines or scripts for transferring data. It's also used in just about every device you can think of: mobile phones and tablets, television sets, printers, routers, media players and other audio equipment. Curl is also the internet transfer backbone for thousands of software applications being used extensively throughout the world today. Curl is feature-rich, thread-safe, well supported and fast. It is also highly portable and works on numerous platforms, including Solaris, NetBSD, FreeBSD, OpenBSD, Linux, Mac OS X, Windows, Darwin, UnixWare, HURD, BeOS, Ultrix, QNX, DOS, Symbian, and many more.
    Downloads: 18 This Week
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  • 3
    iText®, a JAVA PDF library

    iText®, a JAVA PDF library

    PDF Library for Developers

    iText is an open-source PDF library available for Java and .NET (C#). iText allows you to effortlessly generate and manipulate standards-compliant PDF documents with a powerful and feature-rich SDK. With iText, you can create archivable and accessible PDFs, split and merge documents, fill and flatten forms, digitally sign documents, and more. iText add-ons enable additional functionality, such as PDF creation from HTML templates, secure redaction, OCR, and much more. The latest versions of iText build on the success of previous versions and feature an improved document engine, high and low-level programming capabilities, and a more efficient modular structure. iText represents the next level for developers looking to leverage PDF in document workflows. The main project page for iText is now on GitHub, and all the latest releases, code samples, open source add-ons and tools, etc. can be found at https://github.com/itext/.
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    Downloads: 251 This Week
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  • 4
    Fast Artificial Neural Network Library is a free open source neural network library, which implements multilayer artificial neural networks in C with support for both fully connected and sparsely connected networks. Cross-platform execution in both fixed and floating point are supported. It includes a framework for easy handling of training data sets. It is easy to use, versatile, well documented, and fast. Bindings to more than 15 programming languages are available. An easy to read introduction article and a reference manual accompanies the library with examples and recommendations on how to use the library. Several graphical user interfaces are also available for the library.
    Downloads: 42 This Week
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  • 5
    urllib3

    urllib3

    Python HTTP library with thread-safe connection pooling

    urllib3 is a powerful, user-friendly HTTP client for Python. Much of the Python ecosystem already uses urllib3 and you should too. Thread safety, connection pooling. Client-side TLS/SSL verification. File uploads with multipart encoding. Helpers for retrying requests and dealing with HTTP redirects. Support for gzip, deflate, brotli, and zstd encoding. Proxy support for HTTP and SOCKS. 100% test coverage. Professional support for urllib3 is available as part of the Tidelift Subscription. Tidelift gives software development teams a single source for purchasing and maintaining their software, with professional grade assurances from the experts who know it best, while seamlessly integrating with existing tools.
    Downloads: 4 This Week
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  • 6
    WhichBrowser

    WhichBrowser

    Browser sniffing gone too far — A useragent parser library for PHP

    This is an extremely complicated and almost completely useless browser-sniffing library. Useless because you shouldn't use browser sniffing. So stop right now and go read something about feature detecting instead. I'm serious. Go away. You'll thank me later. There is always an exception to the rule. There are valid reasons to do browser sniffing: to improve the user experience or to gather intelligence about which browsers are used on your website. My website is html5test.com and I wanted to know which score belongs to which browser. To do that you need a browser sniffing library. Almost all browsers say they are Netscape 5 and almost all WebKit browsers say they are based on Gecko. Even Internet Explorer 11 now no longer claims to be IE at all, but instead, an unnamed browser that is like Gecko. And it gets worse. That is why it is complicated.
    Downloads: 3 This Week
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  • 7
    CSSBox

    CSSBox

    Pure Java HTML / CSS rendering engine

    CSSBox is an (X)HTML/CSS rendering engine written in pure Java. Its primary purpose is to provide a complete information about the rendered page suitable for further processing. However, it also allows displaying the rendered document.
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    Downloads: 17 This Week
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  • 8
    Coraza

    Coraza

    OWASP Coraza WAF is a golang modsecurity compatible firewall library

    Coraza is an open-source, enterprise-grade, high-performance Web Application Firewall (WAF) ready to protect your beloved applications. It is written in Go, supports ModSecurity SecLang rulesets and is 100% compatible with the OWASP Core Rule Set. Coraza is a drop-in alternative to replace the soon-to-be abandoned Trustwave ModSecurity Engine and supports industry-standard SecLang rule sets. Coraza runs the OWASP Core Rule Set (CRS) to protect your web applications from a wide range of attacks, including the OWASP Top Ten, with a minimum of false alerts. CRS protects from many common attack categories including: SQL Injection (SQLi), Cross Site Scripting (XSS), PHP & Java Code Injection, HTTPoxy, Shellshock, Scripting/Scanner/Bot Detection & Metadata & Error Leakages. Coraza is a library at its core, with many integrations to deploy on-premise Web Application Firewall instances.
    Downloads: 2 This Week
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  • 9
    POCO C++ Libraries

    POCO C++ Libraries

    Cross-platform C++ libraries with a network/internet focus.

    NOTE: Current source code as well as bugs/patches are on GitHub: https://github.com/pocoproject/poco/ C++ class libraries for network-centric, portable applications, integrated perfectly with the C++ Standard Library. Includes network protocols (Sockets, HTTP, FTP, SMTP, POP3, etc.), SQL database access and XML parsing. Licensed under Boost license.
    Downloads: 7 This Week
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    Connect every part of your business to one bank account

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  • 10
    The ftp4j library implements a Java full-featured FTP client. With ftp4j embedded in your application you can: transfer files (upload and download), browse the FTP site (directory listing), create, delete, rename and move directories and files.
    Downloads: 10 This Week
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  • 11

    FSP - File Service Protocol Suite

    UDP File transfer protocol

    FSP - File Service Protocol. FSP is lightweight UDP based protocol for transferring files. It is designed for anonymous transfers over unreliable networks.
    Downloads: 12 This Week
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  • 12
    Brynet

    Brynet

    A Header-Only cross-platform C++ TCP network library

    Header Only Cross-platform high-performance TCP network library using C++ 11. The server uses two network threads and one logic thread, the client uses one network (also process logic) thread. Every packet size is 46 bytes. Every packet contains the client's id. Server broadcast packets to all clients when recv one packet from any client. The client sends one packet when recv packet from the server and the packet's id is equal self.
    Downloads: 1 This Week
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  • 13
    CppServer

    CppServer

    Fast and low latency asynchronous socket server & client C++ library

    Ultra-fast and low latency asynchronous socket server & client C++ library with support TCP, SSL, UDP, HTTP, HTTPS, WebSocket protocols, and 10K connections problem solution. Cross platform (Linux, MacOS, Windows) Asynchronous communication. Supported CPU scalability designs: IO service per thread, thread pool. Supported transport protocols: TCP, SSL, UDP, UDP multicast. Supported Web protocols: HTTP, HTTPS, WebSocket, WebSocket secure. Supported Swagger OpenAPI iterative documentation. Supported message protocol based on Fast Binary Encoding.
    Downloads: 1 This Week
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  • 14
    Martian Proxy

    Martian Proxy

    Martian is a library for building custom HTTP/S proxies

    Martian Proxy is a programmable HTTP proxy designed to be used for testing. Martian is a great tool to use if you want to verify that all (or some subset) of requests are secure. Mock external services at the network layer. Inject headers, modify cookies or perform other mutations of HTTP requests and responses. Verify that pingbacks happen when you think they should. Unwrap encrypted traffic (requires install of CA certificate in browser) By taking advantage of Go cross-compilation, Martian can be deployed anywhere that Go can target. Martian Proxy added support for Go modules since v3.0.0. If you use a Go version that does not support modules, this will break you. The latest version without Go modules support was tagged v2.1.0. For logging of requests and responses a logging modifier is available or HAR logs are available if the -har flag is used. Once Martian is running, you need to configure its behavior.
    Downloads: 1 This Week
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  • 15
    Netfox

    Netfox

    A lightweight, one line setup, iOS / OSX network debugging library

    Netfox provides a quick look on all executed network requests performed by your iOS or OSX app. It grabs all requests - of course yours, requests from 3rd party libraries (such as AFNetworking, Alamofire or else), UIWebViews, and more.
    Downloads: 1 This Week
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  • 16
    Russh

    Russh

    Rust SSH client & server library

    Russh provides a Rust library for implementing SSH clients and servers with a modern, async-friendly design. It exposes building blocks for authentication, channel management, port forwarding, and key handling, allowing you to embed SSH functionality directly into Rust applications. The API is designed to be explicit and composable, making it possible to implement custom behaviors like reverse tunnels, interactive shells, and service multiplexing. Because performance and safety are central, the code leverages Rust’s type system to reduce classes of runtime errors common in network protocol implementations. The project also includes examples and discussion threads that show how other tools integrate it for web-based clients or gateway services. For teams building terminals, proxies, or embedded management planes, it offers a robust foundation without shelling out to external binaries.
    Downloads: 1 This Week
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  • 17
    XSpear

    XSpear

    Powerfull XSS Scanning and Parameter analysis tool&gem

    XSpear is an XSS Scanner on ruby gems. Powerful XSS Scanning and Parameter analysis tool&gem.
    Downloads: 1 This Week
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  • 18
    Early Access iText, a PDF generation library in Java
    Downloads: 13 This Week
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  • 19
    Simple components for Ada

    Simple components for Ada

    A software components library

    The Simple components for Ada library provides implementations of smart pointers for automatically collected objects (using reference counting), object persistence, unbounded and bounded arrays of smart pointers, generic unbounded arrays of private objects and plain pointers, generic sets, maps, arbitrary precision arithmetic, B-trees, directed graphs, directed weighted graphs, stacks, and storage pools. It also includes table management, string editing, IEEE 754 support, and infix expression parsing tools. Implementations of some lock-free shared data structures are provided.
    Downloads: 10 This Week
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  • 20

    libquickmail

    C library for sending e-mail (with attachments) from C/C++

    C library intended to give C/C++ developers a quick and easy way to send e-mail from their applications. Supports multiple To/Cc/Bcc recipients and multiple attachments without size limitation. For the actual SMTP communication either libcurl can be used or the built in SMTP support. The library can also be used to just create a multipart MIME message body. Also comes with a command line application (quickmail) for sending mails (mutiple attachments supported) from command line or scripts. Cross-platform. Binary packages available for Windows (32-bit and 64-bit).
    Downloads: 7 This Week
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  • 21
    dompdf - the PHP 5 HTML to PDF converter. dompdf is a (mostly) CSS compliant HTML rendering engine written in PHP. It supports external stylesheets, inline style tags, and the style attributes of individual HTML elements. Requires PHP 5.
    Downloads: 12 This Week
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  • 22
    PHPCrawl is a high configurable webcrawler/webspider-library written in PHP. It supports filters, limiters, cookie-handling, robots.txt-handling, multiprocessing and much more.
    Downloads: 1 This Week
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  • 23
    HTML Canvas Javascript Library
    A full-featured lightweight wrapper library of the native html canvas element written in Javascript, aimed to make visualization and animation using canvas simpler. Features animation support, layers, event capture, multitouch and many examples.
    Downloads: 1 This Week
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  • 24
    SimpleNet is a small Java network library that should aid in writing fast and lightweight network protocols without having to fuzzle around too much with protocol decisions. It mainly aides in message dispatching and abstraction.
    Downloads: 1 This Week
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  • 25
    UJAC is a collection of Java components that may be useful for your project. It provides a powerful expression interpreter, a iText based document processing engine that generates PDF documents based on XML templates, a charting library and much more.
    Downloads: 1 This Week
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