Projects

A CLI Tool for showing term substitution and outgoing call hierarchy

The Bootstrappable project is about building our compilers etc. from source, without relying on pre-built binaries or generated files. Can we achieve this for GHC?

How can we build reliable, scalable and maintainable computer systems? Over the past couple of months I've written about how we can use ideas from Erlang/OTP, LMAX Disruptor and FoundationDB to answer this question: https://github.com/stevana/armstrong-distributed-systems/blob/main/docs/erlang-is-not-about.md, https://github.com/stevana/pipelined-state-machines, https://github.com/stevana/coroutine-state-machines, https://github.com/stevana/property-based-testing-stateful-systems-tutorial, https://github.com/stevana/supervised-state-machines, https://github.com/stevana/hot-swapping-state-machines. Next step would be to take those loosely coupled ideas, expand upon and combine them into a concrete and coherent plan.

Update the existing example project to support newer versions of GHC (it's currently on 8.6).

The Clash compiler compiles Haskell to VHDL and (System)Verilog. If anyone is interested in working on the compiler, or learning a bit about using Clash come and say hi, no previous knowledge required!

New version of Clipperz password manager implemented in PureScript

The HLS codebase has a lot that could be better documented. I'm going to write a lot of Haddock.

Together we will develop features for a modern web application in Haskell that serves the community

An educational app for a peculiar logical calculus, written with ReflexFRP.

Collaborative knowledge map protocol and interface fully written in Haskell/Purescript.

Too to enable easily modifying haskell source code by manipulating the AST

A vulkan-based, shader-centric, type-heavy Haskell game engine. Ideally we'd be able to make one small game with it.

Parser combinators are neat, but they require you to contort your grammar to avoid things like left recursion. To resolve this problem, we'll be trying to marry GLL parsing techniques with parser combinators.

Haskell bindings to Halide that allow to write high-performance array and image processing kernels directly in Haskell

The pledge system call on OpenBSD is a voluntary security mechanism, that a process can use to restrict the available kernel API. It is used throughout the OpenBSD base system and some ports, to guard against undiscovered exploits, following the defense in depth principle. System calls are aggregated into related groups called promises. It is considered good practice to discard a promise, i.e., access to any part of the kernel API, as soon as it is no longer needed. I have implemented a prototype Haskell binding for pledge, that uses type annotations to incrementally minimize the exposed kernel API. This weekend I plan to work on applying this to a (small) real world application. I intend to add a translation layer to seccomp eBPF at some point, so his is relevant beyond OpenBSD. Come say hi, if you think your application could benefit form this idea, or you have an opinion on it.

Hacking on the Haskell Program Coverage Toolsuite

Looking at auto refactoring Haskell code using SYB (uniplate) on GHC AST

Kickstart the database by implementing the OSV schema export and write advisories for the known vulnerabilities

A simple webapp where you can paste some Haskell code to learn about unfamiliar language features. PureScript prototype to be rewritten in Haskell with the new JavaScript backend.

Tooling for a Katafication code Hackathon

A lambda calculus for file system trees (or: the universal FFI)

The IHP web framework

A desk-booking web application.

A library for probabilistic programming in Haskell

Okapi is a micro web framework for developing web servers in Haskell.

eDSL framework (like compiling with categories but better)

Superfluid is a new digital money allowing time-continuous payment. It is live on EVM chains, and its specification is being written in Haskell. Let's port it to Cardano!

Bazel is an open source build system developed to support large, polyglot projects. Join this project or stop by if you would like to learn about building Haskell with Bazel, help us make it easier to get started, learn when Bazel may add value to your project, or if you're interested in contributing to rules_haskell.

A language to generate slide rules, currently a monadic DSL on top of diagrams, maybe something cooler soon!

PureScript package manager and build tool

This site collects error messages and warnings for Haskell development tools such as GHC, GHCup, and Stack, documenting them with detailed descriptions and examples. We'll work on documenting all the remaining errors and warnings, as well as extending support for the site to additional tools. No specific technical skills other than curiosity, Git, and Markdown are required, but experience with CSS, JavaScript, Hakyll, and of course Haskell are all useful for certain kinds of contributions.

With USort, the sort is you! Currently implementing a web app (with ghc-javascript) based on the existing command-line utility

Dynamically tiling X11 window manager, written and configured in Haskell