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.

  • Gen AI apps are built with MongoDB Atlas Icon
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  • 1
    *NOTE* Migrated to http://github.com/cracklib/cracklib Next generation version of libCrack password checking library. As of Oct 2008 (reflected in 2.8.15 code release), licensed under LGPL.
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    Downloads: 2,589 This Week
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  • 2
    Open source DKIM library, MTA filter implementation and associated tools.
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    Downloads: 96 This Week
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  • 3
    The database access library for C++ programmers that provides the illusion of embedding SQL in regular C++ code, staying entirely within the C++ standard.
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    Downloads: 124 This Week
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  • 4
    OpenZeppelin Contracts

    OpenZeppelin Contracts

    OpenZeppelin Contracts is a library for secure smart contracts

    A library for secure smart contract development. Build on a solid foundation of community-vetted code. OpenZeppelin Contracts uses semantic versioning to communicate backward compatibility of its API and storage layout. To keep your system secure, you should always use the installed code as-is, and neither copy-paste it from online sources nor modify it yourself. The library is designed so that only the contracts and functions you use are deployed, so you don't need to worry about it needlessly increasing gas costs. Reduce the risk of vulnerabilities in your applications by using standard, tested, community-reviewed code.
    Downloads: 6 This Week
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  • Our Free Plans just got better! | Auth0 Icon
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  • 5
    Awesome Privacy

    Awesome Privacy

    A curated list of privacy & security-focused software and services

    Awesome Privacy is a curated directory of privacy-respecting alternatives to mainstream apps and services, organized across many categories like browsers, search, email, messaging, cloud storage, and operating systems. It aims to help you choose tools that reduce tracking, fingerprinting, and data collection without sacrificing usability. Each entry highlights the project’s core properties—such as open source status, end-to-end encryption, and platform availability—so you can evaluate trade-offs quickly. Because product landscapes change fast, the list emphasizes ongoing maintenance and community discussion around quality and trust. It’s useful for privacy newcomers planning a gradual migration as well as experts building a hardened toolchain. The project also surfaces learning resources and practical guidance so you can understand the broader privacy landscape, not just pick tools in isolation.
    Downloads: 5 This Week
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  • 6
    Personal Security Checklist

    Personal Security Checklist

    A compiled checklist of 300+ tips for protecting digital security

    Personal Security Checklist is a comprehensive, plain-language checklist for improving personal digital security and privacy across devices, accounts, and everyday workflows. It’s organized so that complete beginners can make quick, high-impact changes, while advanced users can dig into deeper hardening steps. The guidance spans topics like passwords, 2FA, device encryption, browser hygiene, network safety, backups, and incident response planning. Each section breaks recommendations into actionable, bite-sized items with brief explanations, helping you understand the “why” as well as the “how.” The repository is continuously refined by a large community, which keeps the content practical, vendor-neutral, and up to date with evolving threats and best practices. It also encourages threat modeling, matching the steps you take to the risks you actually face, so you can prioritize effectively without getting overwhelmed.
    Downloads: 3 This Week
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  • 7
    age

    age

    A simple, modern and secure encryption tool (and Go library)

    age is a security-oriented tool and library by Filo Sottile. age is a simple, modern, secure encryption utility (and Go library) that emphasizes minimal configuration and strong defaults. It provides small explicit keys, no complex options, and is designed for UNIX-style composability; you can pipe into it, integrate it into scripts, etc. It supports a clearly defined format and promotes interoperability across implementations (there are Rust, TypeScript, etc). The project is well-suited for personal data encryption, backup use-cases, scripting encryption workflows, and embedding encryption in tools. Because of its design philosophy, it avoids the bloat of many older encryption utilities while maintaining strong cryptographic hygiene. It’s especially useful for developers or system administrators who want to adopt encryption without learning a multitude of options.
    Downloads: 3 This Week
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  • 8
    jCasbin

    jCasbin

    An authorization library that supports access control models

    An authorization library that supports access control models like ACL, RBAC, ABAC for Golang, Java, C/C++, Node.js, Javascript, PHP, Laravel, Python, .NET (C#), Delphi, Rust, Ruby, Swift (Objective-C), Lua (OpenResty), Dart (Flutter) and Elixir. In Casbin, an access control model is abstracted into a CONF file based on the PERM metamodel (Policy, Effect, Request, Matchers). So switching or upgrading the authorization mechanism for a project is just as simple as modifying a configuration. Besides memory and file, Casbin policy can be stored into lots of places. Currently, dozens of databases are supported, from MySQL, Postgres, Oracle to MongoDB, Redis, Cassandra, AWS S3. jCasbin is a powerful and efficient open-source access control library for Java projects. It provides support for enforcing authorization based on various access control models.
    Downloads: 3 This Week
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  • 9
    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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  • Connect every part of your business to one bank account Icon
    Connect every part of your business to one bank account

    North One is a business banking app that integrates cash flow, payments, and budgeting to turn your North One Account into one Connected Bank Account

    North One is proudly built for small businesses, startups and freelancers across America. Make payments easily, keep tabs on your money and put your finances on autopilot through smart integrations with the tools you’re already using. North One was built to make managing money easy so you can focus on running your business. No more branches. No more lines. No more paperwork. Get complete access to your North One Account from your phone or computer, wherever your business takes you. Create Envelopes for taxes, payroll, rent, and anything else automatically.
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  • 10
    multiOTP open source

    multiOTP open source

    PHP strong authentication library, web interface & CLI, OATH certified

    multiOTP is a PHP class, a powerful command line utility and a web interface developed by SysCo systèmes de communication sa in order to provide a completely free and easy operating system independent server side implementation for strong two factors authentication solution. multiOTP supports hardware and software tokens with different One-Time Password algorithms like OATH/HOTP, OATH/TOTP and mOTP (Mobile-OTP). QRcode generation is also embedded in order to support provisioning of Google Authenticator software tokens. SMS code sending is currently implemented for several providers (ASPSMS, Clickatell and IntelliSMS). The data storage of the command line utility is by default flat files based in order to simplify deployment in a few minutes, but MySQL backend is supported too. multiOTP can be easily integrated in RADIUS servers like FreeRADIUS under Linux/Windows or TekRADIUS LT under Windows. multiOTP is also the engine of the credential provider multiOTP Credential Provider.
    Downloads: 13 This Week
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  • 11
    Libkpass is a from-scratch C implementation of reading and writing KeePass 1.x format password databases. Please check github for future updates.
    Downloads: 8 This Week
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  • 12
    LibSecRm - Secure Removal Library

    LibSecRm - Secure Removal Library

    A library for secure deleting data on-the-fly

    LibSecRm (LIBrary for SECure ReMoval) is a set of replacements for these standard C functions which cause data removing from files. The data is first securely wiped on-the-fly, to protect the user's privacy, then the original functions are called. There is NO NEED to rebuild your software, because LibSecRm is a pre-loadable library, meaning you just need to RUN the software with LibSecRm loaded. LibSecRm is also a development library. The following wiping methods are supported: Gutmann-like, random, Schneier, DoD. See the project homepage https://libsecrm.sourceforge.io and the project Wiki in the menu above. To wipe data that was left on the drive by using "normal" delete operations, you can take a look at WipeFreeSpace (https://wipefreespace.sourceforge.io), which wipes the space used by files marked as deleted (and other things, too).
    Downloads: 6 This Week
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  • 13

    cppcrypto

    C++ cryptographic library (modern hash functions, ciphers, KDFs)

    cppcrypto provides optimized implementations of cryptographic primitives. Hash functions: BLAKE, BLAKE2, Echo, Esch, Groestl, JH, Kupyna, MD5, SHA-1, SHA-2, SHA-3, SHAKE, Skein, SM3, Streebog, Whirlpool. Block ciphers: Anubis, Aria, Camellia, CAST-256, Kalyna, Kuznyechik, Mars, Serpent, Simon, SM4, Speck, Threefish, Twofish, and Rijndael (AES) with all block/key sizes. Stream ciphers: HC-128, HC-256, Salsa20, XSalsa20, ChaCha, XChaCha. Encryption modes: CBC, CTR. AEAD modes: Encrypt-then-MAC (EtM), GCM, OCB, ChaCha-Poly1305, Schwaemm. Streaming AEAD. MAC functions: HMAC, Poly1305. Key derivation functions: PBKDF2, scrypt, Argon2, HKDF. Includes sample command-line tools: - 'digest' - for calculating and verifying file checksum(s) using any of the supported hash algorithms (similar to md5sum or RHash). - 'cryptor' - for file encryption using Serpent-256 algorithm in AEAD mode. Check out the cppcrypto web site linked below for programming documentation.
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    Downloads: 3 This Week
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  • 14
    ScardFace is a python3k library for interfacing with smart cards, which supports Plug-and-Play readers inclusion and threading. It also offers classes for manipulating APDU cmds and resps, and use them in a transport-protocol-independent fashion.
    Downloads: 4 This Week
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  • 15
    Hide & Reveal
    Composed of a Java steganographic library and GUI to use steganography. Primarily intended for research communities on security and steganography to implement new dissimulation and steganalysis algorithms. More information at www.hidereveal.org
    Downloads: 1 This Week
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  • 16
    LibHideIP - An IP-hiding library

    LibHideIP - An IP-hiding library

    A library for hiding the local IP address from applications.

    LibHideIP is a library that on-the-fly (by preloading) prevents programs from knowing your IP address. This makes them unable to know and reveal your location, thus helping keep the user's privacy. There is NO NEED to rebuild your software, because LibHideIP is a pre-loadable library, meaning you just need to RUN the software with LibHideIP loaded. LibHideIP is also a development library. See the project homepage https://libhideip.sourceforge.io and the project Wiki in the menu above.
    Downloads: 1 This Week
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  • 17
    PWSLIB3

    PWSLIB3

    Password Safe encrypted databases, Java library

    Java module to create, read and write Password Safe V3 encrypted databases. The package is a mature offspring from project JPasswords and can be used with Java 1.8. There is an API document available.
    Downloads: 1 This Week
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  • 18
    AnCH Framework

    AnCH Framework

    Another C++ Hack

    This project has been migrated to GitHub : https://github.com/vlachenal/anch-framework AnCH framework aims to provide utility classes for some common programming features. Features are implemented to be used as simply as possible. This framework was initially a way to test new C++ specifications (C++11) and to test C++ design patterns and tricks. Only POSIX systems are supported for now. Others could be supported later. (Partial) Doxygen documentation can be found on project home page.
    Downloads: 0 This Week
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  • 19
    AnLib is a PHP library of useful functions and classes to help you build and deploy PHP applications swiftly and easily.
    Downloads: 0 This Week
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  • 20
    This class is intended to block the action of spam bots or robots (as Captcha), employing inteligent tactics on human detection. Made on PHP.
    Downloads: 0 This Week
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  • 21
    BBSGen is an improved Blum-Blum-Shub pseudorandom number generator. It consists of a C library (libbbsgen) and command-line tool (bbsgen). BBSGen can be used in applications and command-line as secure, unpredictable and strong PRNG.
    Downloads: 0 This Week
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  • 22
    The subject of this project is development of the Intrusion Detection System (IDS) with Artificial Neural Network (ANN). This model will allow the implementation of a system capable to analyze and to identify possible intrusions, based on the method of an
    Downloads: 0 This Week
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  • 23
    Clam AntiVirus Client Library provides a simple API to the ClamAV daemon. ClamAVC does not require ClamAV to be installed. ClamAVC communicates with clamd using clamd's documented protocol using either TCP or a local Unix domain socket.
    Downloads: 0 This Week
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  • 24
    Commons-SSH is a thin bridge between different Java SSH implementations libraries. It doesn't contain any crypto-related code and created to be used by projects who doesn't want to care about export control regulations (let client to decide)
    Downloads: 0 This Week
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  • 25
    This is a JavaScript library which gives the ability to use cryptographic functionality abstracted of available technologies on the browser side. It executes a cryptographic function with the fastest technology including Java, JavaScript and Flash.
    Downloads: 0 This Week
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