Forum for people involved in the design and development of Haskell implementations, tools, libraries, and supporting infrastructure.
The 18th Haskell Implementors’ Workshop is to be held on June 5th 2026 alongside ZuriHac and the Haskell Ecosystom Workshop near Zurich. The event is organized by the Haskell Community and hosted by the Haskell Foundation at the University of Applied Sciences of Eastern Switzerland (OST) lakeside campus in Rapperswil, Switzerland. It is a forum for people involved in the design and development of Haskell implementations, tools, libraries, and supporting infrastructure to share their work and to discuss future directions and collaborations with others.
In the past the Haskell Implementors’ Workshop was co-located with ICFP (International Conference on Functional Programming). However, in recent years it has become more and more challenging to attract a large enough audience and sufficiently many speakers for an appealing program. ZuriHac and the Haskell Ecosystem Workshop have become an important annual gathering of a large part of the Haskell community. This year the Haskell Implementors’ Workshop will be co-located with these events to be accessible to a broader audience.
The workshop will be held at the Rapperswil-Jona campus of OST. It is right next to the Rapperswil train station, at Oberseestrasse 10. The Zurihac 2025 site has instructions for transportation between Rapperswil and Zürich.
All talks and presentations will be held in an air-conditioned classroom that will be configured conference-style, which means that most seats won’t have a table or desk attached. During the event, we’ll let you know which additional spaces are good for compiler hacking. We will post the exact room number when that becomes available.
Registrations for both the Haskell Ecosystem Workshop (HEW) and Haskell Implementors’ Workshop (HIW) are managed using the same ticketing system. Please make sure to include a Haskell Implementors’ Workshop ticket in your booking.
Due to space constraints and to ensure that registered participant slots do not go unused, there will be a fee for participation. Fees will be used to cover some of the costs of running the event, the remainder of the cost is sponsored by the Haskell Foundation. The fee depends on participant category:
Enrolled students ($10) are participants who are enrolled full-time at an educational institution.
Other participants ($20) are participants who do not meet the criterion above.
All fees are in US dollars.
You are invited to bring the necessary equipment to work on GHC (laptop, power adapter, etc). Swiss electricity is 220 volts, 50 Hz AC. Swiss power outlets are different than in many European countries, so please bring an appropriate adapter if necessary. Drinking fountains are not common in Europe, so please bring a refillable water bottle.
We will eat lunch in the OST canteen, called Mensa. While Mensa is open from 11:00-13:15, it is very busy from 11:45-12:30 because classes are in session, and they’ve asked that we go before or after. Talks have been scheduled to account for this.
Coffee, tea, and fruit will be provided. There is also easy access to a tap for water. Dinner is on your own. There is a grocery store very near the campus where other products can be purchased as well.
The recordings are available on YouTube.
The Haskell Implementors’ Workshop is an ideal place to describe a Haskell extension, describe works-in-progress, demo a new Haskell-related tool, or even propose future lines of Haskell development. Members of the wider Haskell community are encouraged to attend the workshop - we need your feedback to keep the Haskell ecosystem thriving. Students working with Haskell are especially encouraged to share their work.
The scope covers any of the following topics. There may be some topics that people feel we’ve missed, so by all means submit a proposal even if it doesn’t fit exactly into one of these buckets:
The call for proposals is closed. Lightning talks will be scheduled on the day of the event.
The Haskell Implementors’ Workshop is an ideal place to describe a Haskell extension, describe works-in-progress, demo a new Haskell-related tool, or even propose future lines of Haskell development. Members of the wider Haskell community are encouraged to attend the workshop - we need your feedback to keep the Haskell ecosystem thriving. Students working with Haskell are especially encouraged to share their work.
The scope covers any of the following topics. There may be some topics that people feel we’ve missed, so by all means submit a proposal even if it doesn’t fit exactly into one of these buckets:
We invite proposals from potential speakers for talks and demonstrations. We are aiming for 20-minute talks with 5 minutes for questions and changeovers. We want to hear from people writing compilers, tools, or libraries, people with cool ideas for directions in which we should take the platform, proposals for new features to be implemented, and half-baked crazy ideas. Please submit a talk title and abstract of no more than 300 words.
We will also have a lightning talks session. Lightning talks should be ~7mins and are scheduled on the day of the workshop. Suggested topics for lightning talks are to present a single idea, a work-in-progress project, a problem to intrigue and perplex Haskell implementors, or simply to ask for feedback and collaborators.
The event is organized by the Haskell Community and hosted by the Haskell Foundation at the University of Applied Sciences of Eastern Switzerland (OST). The Haskell Foundation itself is supported by several sponsors.
