Open Source Haskell Internet Software

PostgREST is a standalone web server that turns your PostgreSQL database directly into a RESTful API. The structural constraints and permissions in the database determine the API endpoints and operations. Using PostgREST is an alternative to manual CRUD programming. Custom API servers suffer problems. Writing business logic often duplicates, ignores or hobbles database structure. Object-relational mapping is a leaky abstraction leading to slow imperative code. The PostgREST philosophy establishes a single declarative source of truth: the data itself. It’s easier to ask PostgreSQL to join data for you and let its query planner figure out the details than to loop through rows yourself. It’s easier to assign permissions to db objects than to add guards in controllers. (This is especially true for cascading permissions in data dependencies.) It’s easier to set constraints than to litter code with sanity checks.

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.

PortFusion is a minimalistic, cross-platform, transport-layer distributed reverse / forward proxy for TCP written in Haskell + LLVM and released under GPLv3. A single package that makes the most of each platform by tapping into their unique capabilities, combining this power with an intuitive interface, beautiful design and Haskell's excellent support for unprecedented levels of concurrency and parallelism. It strives for the smallest source code size (< 500 lines) while delivering maximum throughput with near zero overhead.

Elm uses type inference to detect corner cases and give friendly hints. NoRedInk switched to Elm about four years ago, and 300k+ lines later, they still have not had to scramble to fix a confusing runtime exception in production. The compiler guides you safely through your changes, ensuring confidence even through the most wide-reaching refactorings in unfamiliar codebases. Including your own, six months later. All Elm programs are written in the same pattern, eliminating doubt and lengthy discussions when deciding how to build new projects and making it easy to navigate old or foreign codebases. Enjoy Elm's famously helpful error messages. Even on codebases with hundreds of thousands of lines of code, the compilation is done in a blink. Elm has its own virtual DOM implementation, designed for simplicity and speed. All values are immutable in Elm, and the benchmarks show that this helps us generate particularly fast JavaScript code.

The Haskell Web Publisher shall allow website implementation using the functional programming language Haskell. Thereby, accuracy of URIs, data validity, and compliance to security restrictions shall be assured by compiler checks.

Seaweed is a library for the functional programming language Haskell. The current focus of this library is on XML, and the internet. The Haskell Web Publisher (http://hwp.sourceforge.net/) is based on Seaweed.

A set of MediaWiki extensions and other tools developed for the Twelf wiki (http://twelf.plparty.org) that enable a wiki to naturally incorporate logic Twelf in a number of meaningful and useful ways.

WWW-wide translation of HTML pages. This should be run as CGI script or Server module. HTML pages are fetched, translated, links are updated in order to continue translation when the user follows a hyperlink.

Xcerpt is a Query and Transformation Language for XML and Semistructured data. Instead of the navigational approach of XPath-based languages like XSLT or XQuery, Xcerpt uses patterns for querying and is based on concepts of logic programming like unifica

Kaya: A statically typed, imperative cross-platform programming language with type inference, powerful data description capabilities and built-in abstractions and libraries for easy and robust web application development. http://kayalang.org/