Open Source Haskell Software
Sort By:
Haskell Software
Browse free open source Haskell Software and projects below. Use the toggles on the left to filter open source Haskell Software by OS, license, language, programming language, and project status.
-
Our Free Plans just got better! | Auth0You asked, we delivered! Auth0 is excited to expand our Free and Paid plans to include more options so you can focus on building, deploying, and scaling applications without having to worry about your security. Auth0 now, thank yourself later.
-
Deliver secure remote access with OpenVPN.OpenVPN's products provide scalable, secure remote access — giving complete freedom to your employees to work outside the office while securely accessing SaaS, the internet, and company resources.
-
1
Pandoc
The universal markup converter
Pandoc is a universal document converter able to convert files from a multitude of markup formats into another. With Pandoc, you have a swiss-army knife of a converter, able to convert practically any markup format into any other. Pandoc contains a Haskell library for conversions as well as a command-line tool that uses this library. It can convert to and from just about anything-- lightweight markup formats, HTML formats, documentation formats, ebooks, TeX formats, word processor formats and so much more. It understands several useful markdown syntax extensions, such as document metadata, footnotes, tables, and more. If you want strict markdown compatibility however, these extensions can be turned off. Pandoc is no doubt powerful and customizable, but it is important to note that its intermediate representation of a document is less expressive than many of the formats, so it may not produce perfect conversions every time. -
2
FreeArc combines best 7-zip and RAR features: auto-selected LZMA/PPMD/Multimedia compression, 1gb dictionary, exe/dict/delta data filters, updatable solid archives, SFXes, recovery record, AES+Twofish+Serpent encryption, Linux support and much more...
-
3
SimpleX
The first messaging platform operating without user identifiers
Other apps have user IDs: Signal, Matrix, Session, Briar, Jami, Cwtch, etc. SimpleX does not, not even random numbers. This radically improves your privacy. The video shows how you connect to your friend via their 1-time QR-code, in person or via a video link. You can also connect by sharing an invitation link. Temporary anonymous pairwise identifiers SimpleX uses temporary anonymous pairwise addresses and credentials for each user contact or group member. It allows to deliver messages without user profile identifiers, providing better meta-data privacy than alternatives. Many communication platforms are vulnerable to MITM attacks by servers or network providers. To prevent it SimpleX apps pass one-time keys out-of-band when you share an address as a link or a QR code. Double-ratchet protocol. OTR messaging with perfect forward secrecy and break-in recovery. NaCL cryptobox in each queue to prevent traffic correlation between message queues if TLS is compromised. -
4
Gifcurry
The open-source, Haskell-built video editor for GIF makers
The open-source, Haskell-built video editor for GIF makers. Gifcurry is the open-source video editor for GIF makers. It's built with Haskell and works on Linux, Mac, and most likely Windows. There is both a graphical and command line interface. Gifcurry edits your GIFs or videos and turns them into videos or GIFs. You can crop, trim, seek, add text, pick a font, alter the duration, change the size, set the FPS, tweak the color count, enable dithering, import subtitles, and save your creation as either a GIF or video. Before you download Gifcurry, make sure your machine has GTK+, GStreamer, FFmpeg, and ImageMagick. Linux users can download the AppImage or the prebuilt binaries. If you'd rather install it, you can do so via pacman (Arch) or snap. If you're really courageous, you can build it from source. -
Get Avast Free Antivirus | Your top-rated shield against malware and online scamsOur antivirus software scans for security and performance issues and helps you to fix them instantly. It also protects you in real time by analyzing unknown files before they reach your desktop PC or laptop — all for free.
-
5
Wasp
A programming language that understands what a web app is
Wasp (Web Application Specification Language) is a declarative DSL (domain-specific language) for developing, building and deploying modern full-stack web apps with less code. Concepts such as app, page, user, login, frontend, production, etc. are baked into the language, bringing a new level of expressiveness and allowing you to get more work done with fewer lines of code. While describing high-level features with Wasp, you still write the rest of your logic in your favorite technologies (currently React, NodeJS, Prisma). Wasp is in alpha and is therefore likely to change a lot, have bugs and miss important features. Due to its expressiveness, you can create and deploy a production-ready web app from scratch with very few lines of concise, consistent, declarative code. When you need more control than Wasp offers, you can write code in existing technologies such as js/html/css/... and combine it with Wasp code! -
6
koka
Koka language compiler and interpreter
Koka is a strongly typed functional-style language with effect types and handlers. The core of Koka consists of a small set of well-studied language features, like first-class functions, a polymorphic type- and effect system, algebraic data types, and effect handlers. Each of these is composable and avoid the addition of “special” extensions by being as general as possible. Koka tracks the (side) effects of every function in its type, where pure and effectful computations are distinguished. The precise effect typing gives Koka rock-solid semantics backed by well-studied category theory, which makes Koka particularly easy to reason about for both humans and compilers. Effect handlers let you define advanced control abstractions, like exceptions, async/await, or probabilistic programs, as a user library in a typed and composable way. Perceus is an advanced compilation method for reference counting. -
7
FOSSA CLI
Fast, portable and reliable dependency analysis for any codebase
FOSSA CLI is a command-line tool that scans your codebase to identify open-source dependencies and their associated licenses and vulnerabilities. It integrates into CI/CD pipelines to provide automated compliance checks, license audits, and security analysis. Designed for enterprise software teams, FOSSA CLI helps enforce open-source policies at scale and provides accurate, automated insights into third-party software usage through deep analysis of transitive dependencies and ecosystem-specific configurations. -
8
Kmonad
An advanced keyboard manager
KMonad is a cross-platform, advanced keyboard remapping tool written in Haskell. It provides low-level key control, supporting layers, tap-hold combos, multi-tap, macros, and more—even for keyboards without firmware-level customization. -
9
ShellCheck
A static analysis tool for shell scripts
ShellCheck is a GPLv3 tool that provides warnings and possible suggestions for bash/sh shell scripts. ShellCheck finds bugs in your shell scripts. You can cabal, apt, dnf, pkg or brew install it locally right now. ShellCheck highlights and clarifies typical beginner's syntax mistakes and issues that cause a shell to give a cryptic error message. It shows typical intermediate level semantic problems that cause a shell to behave in a abnormally and counter-intuitively. It can also discover ssubtle caveats, corner cases and pitfalls that may cause an user's working script to fail under probable future circumstances. ShellCheck.net is always synchronized to the latest git version, and is the simplest way to give ShellCheck a go. -
Gen AI apps are built with MongoDB AtlasMongoDB Atlas is the developer-friendly database used to build, scale, and run gen AI and LLM-powered apps—without needing a separate vector database. Atlas offers built-in vector search, global availability across 115+ regions, and flexible document modeling. Start building AI apps faster, all in one place.
-
10
Carp
A functional, systems programming language with linear types
Carp is a statically typed, functional programming language designed for real-time and systems programming. It features a Lisp-like syntax, strong compile-time checks, and linear type semantics that ensure memory safety without a garbage collector. Carp targets C as its backend, generating performant and predictable native code while offering functional abstractions and interactive development via REPL. -
11
Clash
Haskell to VHDL/Verilog/SystemVerilog compiler
Clash is a functional hardware description language that borrows both its syntax and semantics from the functional programming language Haskell. It provides a familiar structural design approach to both combinational and synchronous sequential circuits. The Clash compiler transforms these high-level descriptions to low-level synthesizable VHDL, Verilog, or SystemVerilog. Clash is an open-source project, licensed under the permissive BSD2 license, and actively maintained by QBayLogic. The Clash project is a Haskell Foundation affiliated project. Clash is built on Haskell which provides an excellent foundation for well-typed code. Together with Clash's standard library it is easy to build scalable and reusable hardware designs. Load your designs in an interpreter and easily test all your component without needing to setup a test bench. Although Clash offers many features, you sometimes need to directly access VHDL, Verilog, or SystemVerilog directly. -
12
Extism
The Universal Plug-in System. Extend anything with WebAssembly
Extism is a plug-in system for everyone. We've carefully designed it to be flexible, fitting into codebases of all shapes and sizes, but opinionated enough so that things Just Work™ the way they should. Extism's goal is to make all software programmable. You can use Extism in your codebase, regardless of the programming language. We support several environments through our official Host SDKs, and are adding more language support all the time. A plug-in system is software that enables your users or customers to add some logic into certain points in your application. You decide where this logic runs, and your users decide what the plug-in does. Many engineering teams face an ever-growing list of feature requests, often exceeding their bandwidth several times over. How can you ever keep up? Making your product extensible by its end-users is a great way to move some of those features outside the core, and empower customers to make your software more useful for them. -
13
Stack
The Haskell Tool Stack
Stack is a cross-platform build tool for Haskell projects that simplifies dependency management, project setup, and reproducible builds. It provides curated package sets (Stackage), isolated project environments, and consistent tooling for compiling and testing Haskell applications. Stack streamlines workflows for developers by automating many parts of the Haskell toolchain, making it easier to get started and maintain complex codebases. It supports integration with GHC (Glasgow Haskell Compiler) and Hackage. -
14
Cardano Node
The core component that is used to participate in a Cardano
Cardano Node is the core software that powers the Cardano blockchain, a decentralized, proof-of-stake platform for smart contracts and digital assets. Developed in Haskell, the node allows participation in Cardano’s network by validating transactions, producing blocks, and maintaining the ledger. It supports Shelley, Goguen, Basho, and other phases of Cardano’s roadmap, and plays a crucial role in network security and consensus. The node is configurable for different use cases, including running full nodes, relay nodes, or stake pool operators. -
15
crkbd is the firmware and PCB design for the Corne split mechanical keyboard (aka "Corne"), maintained by foostan and the community. It provides QMK/VIA/Vial firmware support, RGB underglow, multiple layouts, and flexible hardware customization.
-
16
Haste
A GHC-based Haskell to JavaScript compiler
A compiler to generate JavaScript code from Haskell. It even has a website and a mailing list. Seamless, type-safe single program framework for client-server communication. Support for modern web technologies such as WebSockets, WebStorage and Canvas. Simple JavaScript interoperability. Generates small, fast programs. Supports all GHC extensions except Template Haskell. Uses standard Haskell libraries. Cabal integration, simple, one-step build; no need for error prone Rube Goldberg machines of Vagrant, VirtualBox, GHC sources and other black magic. Concurrency and MVars with Haste.Concurrent. Unboxed arrays, ByteArrays, StableNames and other low level features. Low-level DOM base library. You have three options for getting Haste: installing from Hackage, from Github or from one of the pre-built binary packages. -
17
Hasura GraphQL Engine
Blazing fast, instant realtime GraphQL APIs on your DB
Hasura is an open-source product that accelerates API development by 10x by giving you GraphQL or REST APIs with built-in authorization on your data, instantly. Run Hasura, locally or in the cloud, and connect it to your new or existing databases to instantly get a production-grade GraphQL API. Developers and architects love Hasura because it takes no time to get started, doesn’t need them to be a GraphQL expert upfront, and saves their teams months of recurring effort in building, shipping, and maintaining their APIs. Hasura’s built-in RLS style authorization engine allows you to conveniently specify authorization rules at a model level, and safely expose the GraphQL API to developers inside or outside your organization. Hasura’s authz engine is enabling agile teams in fast-growing startups as well as powering mission-critical data access in highly regulated environments such as Fortune 500 healthcare, financial services and US federal agencies. -
18
LiquidHaskell
Liquid Types For Haskell
This is the development site of the LiquidHaskell formal verification tool. If you're a LiquidHaskell user (or just curious), you probably want to go to the documentation website instead. LiquidHaskell (LH) refines Haskell's types with logical predicates that let you enforce important properties at compile time. LH warns you that head is not total as it is missing the case for [] and checks that it is total on NonEmpty lists. The input contract propagates to uses of head which are verified by ensuring the arguments are NonEmpty. LH lets you avoid off-by-one errors that can lead to crashes or buffer overflows. Dependent contracts let you specify, e.g. that dotProduct requires equal-sized vectors. LH checks that functions terminate and so warns about the infinite recursion due to the missing case in fib. -
19
Neuron
Future-proof note-taking and publishing based on Zettelkasten
Neuron is a Zettelkasten-based note-taking system and static site generator built in Haskell. It allows users to manage interlinked notes using plain-text Markdown files, which are automatically rendered into a web-based knowledge base. Neuron supports incremental builds, backlinks, and efficient navigation across linked content, making it ideal for personal knowledge management, digital gardens, and wikis. It emphasizes speed, simplicity, and easy version control with Git. -
20
Scotty
Haskell web framework inspired by Ruby's Sinatra, using WAI and Warp
Scotty is a lightweight Haskell web framework inspired by Ruby’s Sinatra. It allows developers to build RESTful web applications and APIs with minimal boilerplate. Scotty is built on top of the WAI (Web Application Interface) and Warp server, making it fast and scalable. It emphasizes simplicity and ease of use, making it ideal for small- to medium-sized services or for developers learning web programming in Haskell. -
21
SimpleXMQ
A reference implementation of the SimpleX Messaging Protocol
A reference implementation of the SimpleX Messaging Protocol for simplex queues over public networks. SimpleXMQ is a message broker for managing message queues and sending messages over a public network. It consists of an SMP server, SMP client library, and SMP agent that implements SMP protocol for client-server communication and SMP agent protocol to manage duplex connections via simplex queues on multiple SMP servers. SMP protocol is inspired by Redis serialization protocol, but it is much simpler - it currently has only 10 client commands and 8 server responses. -
22
nixfmt
The official formatter for Nix code
nixfmt is a code formatter for the Nix expression language, aiming to provide consistent and idiomatic formatting for Nix files. It is written in Haskell and designed to be fast, predictable, and fully automatic with zero configuration. nixfmt helps Nix developers maintain readability and code consistency across large codebases, facilitating collaboration and version control workflows. -
23
tetris
A terminal interface for Tetris
A terminal interface for Tetris. Installation on MacOS and Linux is outlined below. Windows support is questionable, but you can try to install from source. The default game is run by simply executing the tetris command. If the unicode characters look a bit wonky in your terminal, you can also run. People seem to have varying levels of success with the linux binary. Please note that it is compiled dynamically and hence should not be expected to work on most distros. This code is built on top of brick which makes building terminal user interfaces very accessible. -
24
Cryptol
Cryptol: The Language of Cryptography
Cryptol is a domain-specific language (DSL) for specifying and verifying cryptographic algorithms. Developed by Galois, Cryptol provides a high-level mathematical syntax for describing cryptographic primitives and enables formal verification of algorithm properties. It is used in academic, research, and defense sectors to validate correctness and security through symbolic execution and model checking, ensuring critical cryptographic code is free of design flaws. -
25
Duckling
Language, engine, and tooling for testing composable language rules
Duckling is a Haskell library developed by Facebook for parsing and normalizing natural language expressions into structured data. It supports a wide range of entities such as dates, times, durations, distances, temperatures, numbers, and currencies. Designed for use in conversational agents, chatbots, and natural language processing applications, Duckling converts fuzzy user input into a consistent and machine-readable format. It features multi-language support and is widely used in production environments requiring robust entity extraction.
