WG 2.11 - User contributions [en]

WG211/M25Schedule

2025-12-01T15:20:54Z

Sebastian: /* Talks and Schedule */

= IFIP Working Group 2.11, Twenty-fifth Meeting =

== December 2-5, 2025, Stellenbosch, South Africa ==

The meeting will be held in Stellenbosch, South Africa, hosted by [mailto:bfischer@sun.ac.za Bernd Fischer]. The meeting is planned for 3.5 days, with a half day on December 5. More details, program, and registration information will be appearing on this page in the next few weeks.

=== Venue ===

The meeting will be held at the Wallenberg Center of the [http://stias.ac.za/ Stellenbosch Institute for Advanced Study] ([https://maps.app.goo.gl/AZg9SFDFsrLBL8Dr7 Streetview]). This is to the east of the [http://en.wikipedia.org/wiki/Stellenbosch_University Stellenbosch University] Campus ([https://www.sun.ac.za/english/welcome/Documents/Main%20campus%20map%20revised.pdf Campus map]). Most B&B's, hotels, and restaurants are within 10-15mins walk.

Note that STIAS doesn't serve breakfast before the meeting starts, but that should be covered by your B&B.

=== Group dinners ===

Stellenbosch has many restaurants, but they get quite busy from mid-November. I have thus made dinner reservations for 19:00 each night:
* Tuesday: [https://www.devier.co.za De Vier]
* Wednesday: [https://bertusbasson.com/#spek-bone Spek en Bone]
* Thursday: [https://devleispaleis.co.za De Vleispaleis]

For people attending the excursion, I have made a reservation at 19:30:
* Friday: [https://www.de-eetkamer.co.za De Eetkamer]

All restaurants are within walking distance from the old town. All restaurants have vegetarian options available, despite their names ;-).

=== Group excursion ===

I have arranged a group excursion on Friday, Dec 5. We will be visiting Boulder's Beach for penguin watching and take the cable car up to [https://en.wikipedia.org/wiki/Table_Mountain Table Mountain], with time for a walk at the plateau. We will be doing a wine tasting along the way - this is the winelands, after all!

Note that Table Mountain has a notoriously fickle weather, and could be shrouded in clouds (the so called "table cloth") any time. If the [https://www.tablemountain.net/plan-your-visit/getting-here weather] doesn't co-operate, we will drive to Cape of Good Hope as a backup.

Departure will likely be around 8:30 or 9:00, return to Stellenbosch should be around 18:00 or 18:30, depending on traffic.

Please sign up here if you plan to attend.
* Shraddha Barke
* Jacques Carette (+1)
* Sebastian Erdweg (have to leave before dinner)
* Bernd Fischer
* Cezary Kaliszyk
* Ohad Kammar
* Yuito Murase
* Klaus Ostermann
* Chung-Chieh Shan
* Michel Steuwer
* Eric Van Wyk
* Jeremy Yallop
* Julia Lawall

=== Registration fee ===

Registration fee for the meeting is EUR 275 / ZAR 5500; this covers all lunches on the meeting days and the dinners Tuesday - Thursday (including reasonable amounts of drinks ;-). Additional dinner tickets for partners will be EUR 150 / ZAR 3000.

The cost for the [[WG211/M25Schedule#Group excursion|excursion]] on Dec 5 will be EUR 125 / ZAR 2500 (based on 16 people attending; the price will go up slightly if fewer people attend, because of the fixed bus hire costs); this includes transport, entrance fees at Boulder's Beach, the Table Mountain cable car, boxed lunch and wine tasting, and dinner at [https://www.de-eetkamer.co.za De Eetkamer] in Stellenbosch.

Payment is in cash (either in Euros or in Rand) on arrival, or via electronic bank transfer; please mail me for the account details, if you want to use that option. I will issue a signed receipt on University stationary for the amount paid in the currency used.

=== Members attending ===

Please add your name to the following list (alphabetical by last name, please) if you are planning to attend the meeting.

* Jacques Carette
* Sebastian Erdweg
* Bernd Fischer
* Ohad Kammar
* Julia Lawall
* Klaus Ostermann
* Chung-chieh Shan
* Friedrich Steimann
* Eric Van Wyk
* Jeremy Yallop

=== Guests and Observers ===

* [https://michaeldadams.org/ Michael Adams]
* [https://www.microsoft.com/en-us/research/people/sbarke/ Shraddha Barke]
* [https://www.tue.nl/en/research/researchers/loek-cleophas Loek Cleophas] (local observer)
* [https://ckaliszyk.github.io/ Cezary Kaliszyk]
* Yuito Murase (as proxy of Atsushi Igarashi)
* [https://www.moeketsi.me/ Moeketsi Raselimo] (local observer)
* [https://steuwer.info/ Michel Steuwer]

== Talks and Schedule ==

The following people have confirmed they will giving a talk:

* Michael D. Adams
* Shraddha Barke [[WG211/M25Barke| Toward Trustworthy LLM Generation: From Verifiable Proofs to Reliable Agents]]
* Jacques Carette [[WG211/M25Carette| Definite Folds]]
* Sebastian Erdweg: Differential Execution with Lexical Tracing
* Bernd Fischer (or maybe Moeketsi Raselimo) [[WG211/M25Fischer| Learning Lexical Structure of Black-Box Systems via Repeated String Edit Operations]]
* Cezary Kaliszyk
* Ohad Kammar [[WG211/M25Kammar| Intrinsically typed and well-scoped SMTLIB FFI bindings with modular abstract syntax trees (MAST)]]
* Julia Lawall TBD
* Yuito Murase and Atsushi Igarashi [[WG211/M25Murase| Refined^2 Environment Classifiers]]
* Chung-chieh Shan
* Friedrich Steimann [[WG211/M25Steimann| Relative Multiplication of Infinite Relations]]
* Michel Steuwer [[WG211/M25Steuwer| Slotted E-Graphs]]
* Jeremy Yallop [[WG211/M25Yallop| Frex: Dependently Typed Algebraic Simplification]]
* Eric Van Wyk: [[WG211/M25VanWyk| On Scope Graphs and Reference Attribute Grammars: Answering Eelco's Questions]]

== Travel ==

Note that the meeting will be in the southern Summer, just before the local holiday season starts in earnest, and Stellenbosch (and all of South Africa) will be getting busy, so arrange your flights and accommodation early.

==== Visa Information ====

Visitors from [http://en.wikipedia.org/wiki/Visa_policy_of_South_Africa most EU countries, US, Canada, Japan, Australia and most of South America] don't need a visa to visit South Africa. The complete (official) list is available at the [https://www.dha.gov.za/index.php/countries-exempt-from-sa-visas Department of Home Affairs]. Please contact [mailto:bfischer@sun.ac.za Bernd Fischer] if you need a visa to visit South Africa; please note that applications can take substantial amounts of time to get processed (although the backlog has been cleaned up after the last election...)

==== Vaccinations and Prophylaxis ====

South Africa requires yellow fever vaccinations for travelers arriving from a [https://www.southafrica.net/gl/en/travel/article/yellow-fever-entry-requirements risk area]; this includes most of South America and Central Africa, but excludes Europe, North America, Asia, and Oceania. You should probably have up-to-date standard vaccinations (such as tetanus) as you would have for travel in Europe or North America. Malaria prophylaxis is only required if you go to Kruger National Park or Victoria Falls.

The medical system is very good around Stellenbosch, but sometimes less so in other parts of the country. Check with your (travel) insurance whether they cover your trip.

==== Getting to Stellenbosch ====

The closest airport to Stellenbosch is [https://en.wikipedia.org/wiki/Cape_Town_International_Airport Cape Town International (CPT / FACT)]. There are direct flights from London (Virgin, BA), Amsterdam (KLM), Paris (Air France), Frankfurt (Condor, Lufthansa), Munich (Lufthansa), Zuerich (Edelweiss), Istanbul (Turkish Airlines), Doha (Qatar Airways), Dubai (Emirates), Addis Ababa (Ethiopian), Washington (United), Newark (United), Atlanta (Delta), and Singapore (Singapore Airlines). Note that some of these flights are seasonal and operate only during the southern Summer, so they might not show up yet. There are also regional connections to many places in southern Africa (e.g., Windhoek).

Further connections (e.g., from India, East Asia, Australia, or South America) are available with a transfer in Johannesburg. I recommend to fly into Cape Town, if feasible, because the transfer in Johannesburg requires you to clear immigration and customs (like in the US), which can be a bit unpredictable.

Flight prices vary of course wildly. I have recently paid anything between EUR 700 and 1200 for a Germany round trip, and EUR 1500 for a California round trip.

CPT is about 35km from Stellenbosch; there is no public transport, but Uber is widely available, cheap (< EUR 20 to Stellenbosch), and I always take it. Please be aware that taxi touts will try to talk you into a metered taxi as soon as you leave customs; I always politely ignore them.

If you prefer a pre-booked airport shuttle, try:
* [https://bettinashuttle.co.za/ Bettina's]
* [http://www.shuttleup.co.za/ Shuttle Up]

Stellenbosch is small and easily navigable by foot, and the venue is in walking distance to most hotels and B&Bs. You won't need a rental car unless you are planning to go on a road-trip before or after the conference. There is no public transport in Stellenbosch; do *not* take the train to Cape Town, or a minibus taxi.

==== Accommodation ====

Stellenbosch does not have big corporate hotels but offers a wide variety of different smaller accommodation options. Most centrally located B&Bs (look for the "Stellenbosch Central" or "Mostertsdrift" areas) will be in the range from EUR 80 to EUR 150 per night; there are also Airbnb-style accommodations but they tend to be more in the suburbs, and are not necessarily cheaper. Many wine farms offer luxury accommodation, but they are typically out of town and require a rental car.

Below are a number of guest houses covering different price ranges. Note that I haven't stayed in any of these... Please make your own arrangements and please note that places begin to fill up.

'''Between Stias and the town center''':
* [https://avenuesguesthouse.co.za/ Avenues Guesthouse], 32 Die Laan
* [https://beauclair-guest-cottage.hotels-of-stellenbosch.com/en/ Beauclair Guest Cottage], 1 Coetzenburg Road
* [https://www.bonneesperance.com/ Bonne Esperance], corner of Neethling and Van Riebeeck
* [https://caledon-villa.hotels-of-stellenbosch.com/en/ Caledon Villa], 7 Neethling Street
* [https://www.dehaasliving.co.za/die-laan-2/ De Haas Luxury Living - Die Laan], 2 Die Laan
* [https://www.dehaasliving.co.za/die-laan-40/ De Haas Luxury Living - Die Laan 40], 40 Die Laan
* [https://www.evergreenmanor.co.za/ Evergreen Manor], 11 Murray Street
* [https://koloniestuin.co.za/ Kolonie's Tuin], 22 Die Laan
* [https://www.laanhof.co.za/ Laanhof], 28 Die Laan (self-catering)
* [https://www.lifeandleisure.co.za/ Life & Leisure], 20 Van Riebeeck St
* [https://www.middedorp.com/ Middedorp Manor], 14 Neethling Street
* [https://www.minseriecollection.co.za/ Minserie Collection], Minserie Street (self-catering)
* [https://thelivingjourneycollection.co.za/river-manor/ River Manor], 6-8 Die Laan
* [https://www.roosenwijn.co.za/ Roosenwijn Guesthouse], 14 Van Riebeeck Street
* [https://thelivingjourneycollection.co.za/river-manor/ De Haas Luxury Living - Villa Grande], 1 Keeroom Street

'''Mostertsdrift''' (east of Stias):
* [https://www.5-seasons.co.za/ 5 Seasons Guesthouse], 60 Van Der Stel Street
* [https://lanzerac.co.za/ Lanzerac Wine Estate], Lanzerac Road (wine estate in walking distance from Stias)
* [https://www.stellenboschmanor.com/ Stellenbosch Manor], 2 Van Der Stel Street
* [https://summerwood.co.za/ Summerwood Guest House], 28 Jonkershoek Road
* [https://vanderstelmanor.com/ Van Der Stel Manor], 64 Van Der Stel Street

'''Town center''':
* [https://www.batavia-stellenbosch.co.za/ Batavia Boutique Hotel], 12 Louw Street
* [https://coopmanhuijs.co.za/ Coopmanhuijs Boutique Hotel & Spa], 33 Church Stree
* [https://www.eendracht-hotel.com/ Eendracht Hotel & Self Catering], 160 Drop Street
* [https://www.justjoey.co.za/ Just Joey Lodge], 13 Noordwal-Wes
* [https://stellenboschhotel.co.za/ Stellenbosch Hotel], corner of Dorp & Andringa

==== Security ====

South Africa has a reputation as an unsafe country but most crimes happen in township areas, and the center of Stellenbosch is generally safe; walking around town, or from town to the guesthouses in Mostertsdrift is fine, even after dinner. However, there are a few things to keep in mind:
* Do not flash your valuables (phone, wallet, camera) in public.
* Do not hand over your ATM/credit card - servers will bring a machine to your table (or will ask you to pay at the counter); if you withdraw money from an ATM, check that nobody is lurking around, and do not accept "help" from people.
* Do '''not''' walk or drive into any township (in Stellenbosch, that means Kayamandi and Cloetesville); if you are interested, you can book guided tours.
* Do '''not''' take the train between Cape Town and Stellenbosch (or trains around Cape Town).

==== Weather ====

Early December is late spring in South Africa. The weather in Stellenbosch ''should'' be nice - the average day-time highs are around 25C, night-time lows around 15C, and it ''should'' be dry. However, there are chances of an early heat wave, with temperatures above 30C, or (fortunately less likely) a late rain front with temperatures dropping by 5-10 degrees.

==== Pre- / post-meeting excursions ====

Here are a few ideas if you are planning to spend a few extra days in Stellenbosch or travel around the country:
* Spend the weekend in Cape Town and explore the city - Table Mountain is certainly a prime target. You could also go to Kirstenbosch Botanical Garden (although the prime bloom will be over then), and even climb Table Mountain from there (although this could be hot and strenuous that time of the year). Cape Town has quite a lot of night life, especially on the weekend.
* Explore the Stellenbosch surroundings. For this, you should probably get a rental car. There are literally hundreds of wine farms in the surroundings, if you want to go for a tasting. The Paarl Taal Monument (monument to the Afrikaans language) is an interesting cultural experience, and you can go on to the Paarl rock (large granite Boulder). Franschhoeck is a another cute town.
* Get out to the Cederberg Mountains - a nice mountainous area about 2-3hours north of Cape Town, with nice mountain walks (Wolfberg Cracks, some caves). You could stay at Clanwilliam, or look for a place in the mountain reserve (look for Algeria). The roads are mostly dirt (ie unpaved) but we have driven them in a Polo...
* Hike the Bosmanskloof Traverse (either as an overnight hike, or as a day-hike), staying in McGregor or Grayton.
* Go to Calitzdorp for Port tasting, Oudtshoorn for the ostriches (and the very tourist-trappy Cango Caves, a huge limestone cave), and drive some of the old Mountain passes, like [http://en.wikipedia.org/wiki/Swartberg_Pass Swartbergpass] into Prince Albert, a quaint Karoo town, and "poorts" (i.e., mountain notches), like [https://en.wikipedia.org/wiki/Seweweekspoort| Seweweekspoort].
* Go shark cage diving in Struisbaai.

Except for the Cape Town weekend, most trips will require a rental car. You can get an uber or a dedicated driver for a wine tasting tour, which is probably a smart idea in the first place...

'''Safaris.'''
There are no lions running around in Stellenbosch ;-). The closest ones are at the [http://www.lionrescue.org.za/ Drakenstein Lion Park], which is basically a retirement home for lions. There are a few private game reserves within two to three hours drive of Stellenbosch (e.g., [https://grgamelodge.co.za/ Garden Route Game Lodge] or [http://www.sanbona.com/propertydefault.asp?MicroSiteID=3 Sanbona]), but they are not cheap. The closest National Parks with substantial wildlife are [http://www.sanparks.co.za/parks/mountain_zebra/ Mountain Zebra NP] and [http://www.sanparks.org/parks/addo/ Addo Elephant NP] (about 8-10hrs drive from Stellenbosch, but Addo is quite close to Port Elizabeth, which is one hour by plane from Cape Town). If you plan to visit [http://www.sanparks.org/parks/kruger/ Krueger NP] you should probably fly with a stop-over in Johannesburg, and plan on at least four extra days.

==== Arrivals and departures of attendants ====

* Friedrich will arrive on Monday morning (Condor flight DE2290, ETA 10:45 am) and leave on Friday evening (DE2291 at 7:50 pm); will stay at Evergreen Manor.
* Sebastian will arrive on Monday morning (Condor flight DE2290, ETA 10:45 am) and leave on Friday evening (DE2291 at 7:50 pm); will stay at Evergreen Manor.
* Julia will arrive on Monday morning at 5:50am (Air France from Paris) and leave on the following Monday morning at 7:55am; staying at The Avenues Guest House.
* Jacques will arrive a whole week before, Sunday Nov. 23, stay in Cape Town, then get to Stellenbosch on Monday 1 December, and leave on Saturday Dec 6 at 5 PM (Turkish Airlines TK 45). Staying at Laanhof.
* Shraddha will arrive on 1st Dec 11.40am and leave on Sunday 7th Dec 9.30pm; staying at the 5 Seasons Guest House.

WG211/M25Schedule

2025-11-22T11:53:38Z

Sebastian: /* Arrivals and departures of attendants */

= IFIP Working Group 2.11, Twenty-fifth Meeting =

== December 2-5, 2025, Stellenbosch, South Africa ==

The meeting will be held in Stellenbosch, South Africa, hosted by [mailto:bfischer@sun.ac.za Bernd Fischer]. The meeting is planned for 3.5 days, with a half day on December 5. More details, program, and registration information will be appearing on this page in the next few weeks.

=== Venue ===

The meeting will be held at the Wallenberg Center of the [http://stias.ac.za/ Stellenbosch Institute for Advanced Study] ([https://maps.app.goo.gl/AZg9SFDFsrLBL8Dr7 Streetview]). This is to the east of the [http://en.wikipedia.org/wiki/Stellenbosch_University Stellenbosch University] Campus ([https://www.sun.ac.za/english/welcome/Documents/Main%20campus%20map%20revised.pdf Campus map]). Most B&B's, hotels, and restaurants are within 10-15mins walk.

Note that STIAS doesn't serve breakfast before the meeting starts, but that should be covered by your B&B.

=== Group dinners ===

Stellenbosch has many restaurants, but they get quite busy from mid-November. I have thus made dinner reservations for 19:00 each night:
* Tuesday: [https://www.devier.co.za De Vier]
* Wednesday: [https://bertusbasson.com/#spek-bone Spek en Bone]
* Thursday: [https://devleispaleis.co.za De Vleispaleis]

For people attending the excursion, I have made a reservation at 19:30:
* Friday: [https://www.de-eetkamer.co.za De Eetkamer]

All restaurants are within walking distance from the old town. All restaurants have vegetarian options available, despite their names ;-).

=== Group excursion ===

I have arranged a group excursion on Friday, Dec 5. We will be visiting Boulder's Beach for penguin watching and take the cable car up to [https://en.wikipedia.org/wiki/Table_Mountain Table Mountain], with time for a walk at the plateau. We will be doing a wine tasting along the way - this is the winelands, after all!

Note that Table Mountain has a notoriously fickle weather, and could be shrouded in clouds (the so called "table cloth") any time. If the [https://www.tablemountain.net/plan-your-visit/getting-here weather] doesn't co-operate, we will drive to Cape of Good Hope as a backup.

Departure will likely be around 8:30 or 9:00, return to Stellenbosch should be around 18:00 or 18:30, depending on traffic.

Please sign up here if you plan to attend.
* Shraddha Barke
* Jacques Carette (+1)
* Sebastian Erdweg (have to leave before dinner)
* Bernd Fischer
* Cezary Kaliszyk
* Ohad Kammar
* Yuito Murase
* Klaus Ostermann
* Chung-Chieh Shan
* Michel Steuwer
* Eric Van Wyk
* Jeremy Yallop

=== Registration fee ===

Registration fee for the meeting is EUR 275 / ZAR 5500; this covers all lunches on the meeting days and the dinners Tuesday - Thursday (including reasonable amounts of drinks ;-). Additional dinner tickets for partners will be EUR 150 / ZAR 3000.

The cost for the [[WG211/M25Schedule#Group excursion|excursion]] on Dec 5 will be EUR 125 / ZAR 2500 (based on 16 people attending; the price will go up slightly if fewer people attend, because of the fixed bus hire costs); this includes transport, entrance fees at Boulder's Beach, the Table Mountain cable car, boxed lunch and wine tasting, and dinner at [https://www.de-eetkamer.co.za De Eetkamer] in Stellenbosch.

Payment is in cash (either in Euros or in Rand) on arrival, or via electronic bank transfer; please mail me for the account details, if you want to use that option. I will issue a signed receipt on University stationary for the amount paid in the currency used.

=== Members attending ===

Please add your name to the following list (alphabetical by last name, please) if you are planning to attend the meeting.

* Jacques Carette
* Sebastian Erdweg
* Bernd Fischer
* Ohad Kammar
* Julia Lawall
* Klaus Ostermann
* Chung-chieh Shan
* Friedrich Steimann
* Eric Van Wyk
* Jeremy Yallop

=== Guests and Observers ===

* [https://michaeldadams.org/ Michael Adams]
* [https://www.microsoft.com/en-us/research/people/sbarke/ Shraddha Barke]
* [https://www.tue.nl/en/research/researchers/loek-cleophas Loek Cleophas] (local observer)
* [https://ckaliszyk.github.io/ Cezary Kaliszyk]
* Yuito Murase (as proxy of Atsushi Igarashi)
* [https://www.moeketsi.me/ Moeketsi Raselimo] (local observer)
* [https://steuwer.info/ Michel Steuwer]

== Talks and Schedule ==

The following people have confirmed they will giving a talk:

* Michael D. Adams
* Shraddha Barke [[WG211/M25Barke | Toward Trustworthy LLM Generation: From Verifiable Proofs to Reliable Agents]]
* Jacques Carette [[WG211/M25Carette| Definite Folds]]
* Sebastian Erdweg
* Bernd Fischer (or maybe Moeketsi Raselimo) [[WG211/M25Fischer| Learning Lexical Structure of Black-Box Systems via Repeated String Edit Operations]]
* Cezary Kaliszyk
* Ohad Kammar [[WG211/M25Kammar| Intrinsically typed and well-scoped SMTLIB FFI bindings with modular abstract syntax trees (MAST)]]
* Julia Lawall TBD
* Yuito Murase and Atsushi Igarashi [[WG211/M25Murase| Refined^2 Environment Classifiers]]
* Chung-chieh Shan
* Friedrich Steimann [[WG211/M25Steimann | Relative Multiplication of Infinite Relations ]]
* Michel Steuwer [[WG211/M25Steuwer | Slotted E-Graphs ]]
* Jeremy Yallop [[WG211/M25Yallop| Frex: Dependently Typed Algebraic Simplification]]
* Eric Van Wyk TBD

== Travel ==

Note that the meeting will be in the southern Summer, just before the local holiday season starts in earnest, and Stellenbosch (and all of South Africa) will be getting busy, so arrange your flights and accommodation early.

==== Visa Information ====

Visitors from [http://en.wikipedia.org/wiki/Visa_policy_of_South_Africa most EU countries, US, Canada, Japan, Australia and most of South America] don't need a visa to visit South Africa. The complete (official) list is available at the [https://www.dha.gov.za/index.php/countries-exempt-from-sa-visas Department of Home Affairs]. Please contact [mailto:bfischer@sun.ac.za Bernd Fischer] if you need a visa to visit South Africa; please note that applications can take substantial amounts of time to get processed (although the backlog has been cleaned up after the last election...)

==== Vaccinations and Prophylaxis ====

South Africa requires yellow fever vaccinations for travelers arriving from a [https://www.southafrica.net/gl/en/travel/article/yellow-fever-entry-requirements risk area]; this includes most of South America and Central Africa, but excludes Europe, North America, Asia, and Oceania. You should probably have up-to-date standard vaccinations (such as tetanus) as you would have for travel in Europe or North America. Malaria prophylaxis is only required if you go to Kruger National Park or Victoria Falls.

The medical system is very good around Stellenbosch, but sometimes less so in other parts of the country. Check with your (travel) insurance whether they cover your trip.

==== Getting to Stellenbosch ====

The closest airport to Stellenbosch is [https://en.wikipedia.org/wiki/Cape_Town_International_Airport Cape Town International (CPT / FACT)]. There are direct flights from London (Virgin, BA), Amsterdam (KLM), Paris (Air France), Frankfurt (Condor, Lufthansa), Munich (Lufthansa), Zuerich (Edelweiss), Istanbul (Turkish Airlines), Doha (Qatar Airways), Dubai (Emirates), Addis Ababa (Ethiopian), Washington (United), Newark (United), Atlanta (Delta), and Singapore (Singapore Airlines). Note that some of these flights are seasonal and operate only during the southern Summer, so they might not show up yet. There are also regional connections to many places in southern Africa (e.g., Windhoek).

Further connections (e.g., from India, East Asia, Australia, or South America) are available with a transfer in Johannesburg. I recommend to fly into Cape Town, if feasible, because the transfer in Johannesburg requires you to clear immigration and customs (like in the US), which can be a bit unpredictable.

Flight prices vary of course wildly. I have recently paid anything between EUR 700 and 1200 for a Germany round trip, and EUR 1500 for a California round trip.

CPT is about 35km from Stellenbosch; there is no public transport, but Uber is widely available, cheap (< EUR 20 to Stellenbosch), and I always take it. Please be aware that taxi touts will try to talk you into a metered taxi as soon as you leave customs; I always politely ignore them.

If you prefer a pre-booked airport shuttle, try:
* [https://bettinashuttle.co.za/ Bettina's]
* [http://www.shuttleup.co.za/ Shuttle Up]

Stellenbosch is small and easily navigable by foot, and the venue is in walking distance to most hotels and B&Bs. You won't need a rental car unless you are planning to go on a road-trip before or after the conference. There is no public transport in Stellenbosch; do *not* take the train to Cape Town, or a minibus taxi.

==== Accommodation ====

Stellenbosch does not have big corporate hotels but offers a wide variety of different smaller accommodation options. Most centrally located B&Bs (look for the "Stellenbosch Central" or "Mostertsdrift" areas) will be in the range from EUR 80 to EUR 150 per night; there are also Airbnb-style accommodations but they tend to be more in the suburbs, and are not necessarily cheaper. Many wine farms offer luxury accommodation, but they are typically out of town and require a rental car.

Below are a number of guest houses covering different price ranges. Note that I haven't stayed in any of these... Please make your own arrangements and please note that places begin to fill up.

'''Between Stias and the town center''':
* [https://avenuesguesthouse.co.za/ Avenues Guesthouse], 32 Die Laan
* [https://beauclair-guest-cottage.hotels-of-stellenbosch.com/en/ Beauclair Guest Cottage], 1 Coetzenburg Road
* [https://www.bonneesperance.com/ Bonne Esperance], corner of Neethling and Van Riebeeck
* [https://caledon-villa.hotels-of-stellenbosch.com/en/ Caledon Villa], 7 Neethling Street
* [https://www.dehaasliving.co.za/die-laan-2/ De Haas Luxury Living - Die Laan], 2 Die Laan
* [https://www.dehaasliving.co.za/die-laan-40/ De Haas Luxury Living - Die Laan 40], 40 Die Laan
* [https://www.evergreenmanor.co.za/ Evergreen Manor], 11 Murray Street
* [https://koloniestuin.co.za/ Kolonie's Tuin], 22 Die Laan
* [https://www.laanhof.co.za/ Laanhof], 28 Die Laan (self-catering)
* [https://www.lifeandleisure.co.za/ Life & Leisure], 20 Van Riebeeck St
* [https://www.middedorp.com/ Middedorp Manor], 14 Neethling Street
* [https://www.minseriecollection.co.za/ Minserie Collection], Minserie Street (self-catering)
* [https://thelivingjourneycollection.co.za/river-manor/ River Manor], 6-8 Die Laan
* [https://www.roosenwijn.co.za/ Roosenwijn Guesthouse], 14 Van Riebeeck Street
* [https://thelivingjourneycollection.co.za/river-manor/ De Haas Luxury Living - Villa Grande], 1 Keeroom Street

'''Mostertsdrift''' (east of Stias):
* [https://www.5-seasons.co.za/ 5 Seasons Guesthouse], 60 Van Der Stel Street
* [https://lanzerac.co.za/ Lanzerac Wine Estate], Lanzerac Road (wine estate in walking distance from Stias)
* [https://www.stellenboschmanor.com/ Stellenbosch Manor], 2 Van Der Stel Street
* [https://summerwood.co.za/ Summerwood Guest House], 28 Jonkershoek Road
* [https://vanderstelmanor.com/ Van Der Stel Manor], 64 Van Der Stel Street

'''Town center''':
* [https://www.batavia-stellenbosch.co.za/ Batavia Boutique Hotel], 12 Louw Street
* [https://coopmanhuijs.co.za/ Coopmanhuijs Boutique Hotel & Spa], 33 Church Stree
* [https://www.eendracht-hotel.com/ Eendracht Hotel & Self Catering], 160 Drop Street
* [https://www.justjoey.co.za/ Just Joey Lodge], 13 Noordwal-Wes
* [https://stellenboschhotel.co.za/ Stellenbosch Hotel], corner of Dorp & Andringa

==== Security ====

South Africa has a reputation as an unsafe country but most crimes happen in township areas, and the center of Stellenbosch is generally safe; walking around town, or from town to the guesthouses in Mostertsdrift is fine, even after dinner. However, there are a few things to keep in mind:
* Do not flash your valuables (phone, wallet, camera) in public.
* Do not hand over your ATM/credit card - servers will bring a machine to your table (or will ask you to pay at the counter); if you withdraw money from an ATM, check that nobody is lurking around, and do not accept "help" from people.
* Do '''not''' walk or drive into any township (in Stellenbosch, that means Kayamandi and Cloetesville); if you are interested, you can book guided tours.
* Do '''not''' take the train between Cape Town and Stellenbosch (or trains around Cape Town).

==== Weather ====

Early December is late spring in South Africa. The weather in Stellenbosch ''should'' be nice - the average day-time highs are around 25C, night-time lows around 15C, and it ''should'' be dry. However, there are chances of an early heat wave, with temperatures above 30C, or (fortunately less likely) a late rain front with temperatures dropping by 5-10 degrees.

==== Pre- / post-meeting excursions ====

Here are a few ideas if you are planning to spend a few extra days in Stellenbosch or travel around the country:
* Spend the weekend in Cape Town and explore the city - Table Mountain is certainly a prime target. You could also go to Kirstenbosch Botanical Garden (although the prime bloom will be over then), and even climb Table Mountain from there (although this could be hot and strenuous that time of the year). Cape Town has quite a lot of night life, especially on the weekend.
* Explore the Stellenbosch surroundings. For this, you should probably get a rental car. There are literally hundreds of wine farms in the surroundings, if you want to go for a tasting. The Paarl Taal Monument (monument to the Afrikaans language) is an interesting cultural experience, and you can go on to the Paarl rock (large granite Boulder). Franschhoeck is a another cute town.
* Get out to the Cederberg Mountains - a nice mountainous area about 2-3hours north of Cape Town, with nice mountain walks (Wolfberg Cracks, some caves). You could stay at Clanwilliam, or look for a place in the mountain reserve (look for Algeria). The roads are mostly dirt (ie unpaved) but we have driven them in a Polo...
* Hike the Bosmanskloof Traverse (either as an overnight hike, or as a day-hike), staying in McGregor or Grayton.
* Go to Calitzdorp for Port tasting, Oudtshoorn for the ostriches (and the very tourist-trappy Cango Caves, a huge limestone cave), and drive some of the old Mountain passes, like [http://en.wikipedia.org/wiki/Swartberg_Pass Swartbergpass] into Prince Albert, a quaint Karoo town, and "poorts" (i.e., mountain notches), like [https://en.wikipedia.org/wiki/Seweweekspoort| Seweweekspoort].
* Go shark cage diving in Struisbaai.

Except for the Cape Town weekend, most trips will require a rental car. You can get an uber or a dedicated driver for a wine tasting tour, which is probably a smart idea in the first place...

'''Safaris.'''
There are no lions running around in Stellenbosch ;-). The closest ones are at the [http://www.lionrescue.org.za/ Drakenstein Lion Park], which is basically a retirement home for lions. There are a few private game reserves within two to three hours drive of Stellenbosch (e.g., [https://grgamelodge.co.za/ Garden Route Game Lodge] or [http://www.sanbona.com/propertydefault.asp?MicroSiteID=3 Sanbona]), but they are not cheap. The closest National Parks with substantial wildlife are [http://www.sanparks.co.za/parks/mountain_zebra/ Mountain Zebra NP] and [http://www.sanparks.org/parks/addo/ Addo Elephant NP] (about 8-10hrs drive from Stellenbosch, but Addo is quite close to Port Elizabeth, which is one hour by plane from Cape Town). If you plan to visit [http://www.sanparks.org/parks/kruger/ Krueger NP] you should probably fly with a stop-over in Johannesburg, and plan on at least four extra days.

==== Arrivals and departures of attendants ====

* Friedrich will arrive on Monday morning (Condor flight DE2290, ETA 10:45 am) and leave on Friday evening (DE2291 at 7:50 pm); will stay at Evergreen Manor.
* Sebastian will arrive on Monday morning (Condor flight DE2290, ETA 10:45 am) and leave on Friday evening (DE2291 at 7:50 pm); will stay at Evergreen Manor.
* Julia will arrive on Monday morning at 5:50am (Air France from Paris) and leave on the following Monday morning at 7:55am; staying at The Avenues Guest House.
* Jacques will arrive a whole week before, Sunday Nov. 23, stay in Cape Town, then get to Stellenbosch on Monday 1 December, and leave on Saturday Dec 6 at 5 PM (Turkish Airlines TK 45). Staying at Laanhof.
* Shraddha will arrive on 1st Dec 11.40am and leave on Sunday 7th Dec 9.30pm; staying at the 5 Seasons Guest House.

WG211/M25Schedule

2025-11-19T06:35:55Z

Sebastian:

= IFIP Working Group 2.11, Twenty-fifth Meeting =

== December 2-5, 2025, Stellenbosch, South Africa ==

The meeting will be held in Stellenbosch, South Africa, hosted by [mailto:bfischer@sun.ac.za Bernd Fischer]. The meeting is planned for 3.5 days, with a half day on December 5. More details, program, and registration information will be appearing on this page in the next few weeks.

=== Venue ===

The meeting will be held at the Wallenberg Center of the [http://stias.ac.za/ Stellenbosch Institute for Advanced Study] ([https://maps.app.goo.gl/AZg9SFDFsrLBL8Dr7 Streetview]). This is to the east of the [http://en.wikipedia.org/wiki/Stellenbosch_University Stellenbosch University] Campus ([https://www.sun.ac.za/english/welcome/Documents/Main%20campus%20map%20revised.pdf Campus map]). Most B&B's, hotels, and restaurants are within 10-15mins walk.

Note that STIAS doesn't serve breakfast before the meeting starts, but that should be covered by your B&B.

=== Group dinners ===

Stellenbosch has many restaurants, but they get quite busy from mid-November. I have thus made dinner reservations for 19:00 each night:
* Tuesday: [https://www.devier.co.za De Vier]
* Wednesday: [https://bertusbasson.com/#spek-bone Spek en Bone]
* Thursday: [https://devleispaleis.co.za De Vleispaleis]

For people attending the excursion, I have made a reservation at 19:30:
* Friday: [https://www.de-eetkamer.co.za De Eetkamer]

All restaurants are within walking distance from the old town. All restaurants have vegetarian options available, despite their names ;-).

=== Group excursion ===

I have arranged a group excursion on Friday, Dec 5. We will be visiting Boulder's Beach for penguin watching and take the cable car up to [https://en.wikipedia.org/wiki/Table_Mountain Table Mountain], with time for a walk at the plateau. We will be doing a wine tasting along the way - this is the winelands, after all!

Note that Table Mountain has a notoriously fickle weather, and could be shrouded in clouds (the so called "table cloth") any time. If the [https://www.tablemountain.net/plan-your-visit/getting-here weather] doesn't co-operate, we will drive to Cape of Good Hope as a backup.

Departure will likely be around 8:30 or 9:00, return to Stellenbosch should be around 18:00 or 18:30, depending on traffic.

Please sign up here if you plan to attend.
* Shraddha Barke
* Jacques Carette (+1)
* Sebastian Erdweg (have to leave before dinner)
* Bernd Fischer
* Cezary Kaliszyk
* Ohad Kammar
* Yuito Murase
* Klaus Ostermann
* Chung-Chieh Shan
* Michel Steuwer
* Eric Van Wyk
* Jeremy Yallop

=== Registration fee ===

Registration fee for the meeting is EUR 275 / ZAR 5500; this covers all lunches on the meeting days and the dinners Tuesday - Thursday (including reasonable amounts of drinks ;-). Additional dinner tickets for partners will be EUR 150 / ZAR 3000.

The cost for the [[WG211/M25Schedule#Group excursion|excursion]] on Dec 5 will be EUR 125 / ZAR 2500 (based on 16 people attending; the price will go up slightly if fewer people attend, because of the fixed bus hire costs); this includes transport, entrance fees at Boulder's Beach, the Table Mountain cable car, boxed lunch and wine tasting, and dinner at [https://www.de-eetkamer.co.za De Eetkamer] in Stellenbosch.

Payment is in cash (either in Euros or in Rand) on arrival, or via electronic bank transfer; please mail me for the account details, if you want to use that option. I will issue a signed receipt on University stationary for the amount paid in the currency used.

=== Members attending ===

Please add your name to the following list (alphabetical by last name, please) if you are planning to attend the meeting.

* Jacques Carette
* Sebastian Erdweg
* Bernd Fischer
* Ohad Kammar
* Julia Lawall
* Klaus Ostermann
* Chung-chieh Shan
* Ulrik Pagh Schultz Lundquist
* Friedrich Steimann
* Eric Van Wyk
* Jeremy Yallop

=== Guests and Observers ===

* [https://michaeldadams.org/ Michael Adams]
* [https://www.microsoft.com/en-us/research/people/sbarke/ Shraddha Barke]
* [https://www.tue.nl/en/research/researchers/loek-cleophas Loek Cleophas] (local observer)
* [https://ckaliszyk.github.io/ Cezary Kaliszyk]
* Yuito Murase (as proxy of Atsushi Igarashi)
* [https://www.moeketsi.me/ Moeketsi Raselimo] (local observer)
* [https://steuwer.info/ Michel Steuwer]

== Talks and Schedule ==

The following people have confirmed they will giving a talk:

* Michael D. Adams
* Shraddha Barke
* Jacques Carette [[WG211/M25Carette| Definite Folds]]
* Sebastian Erdweg
* Bernd Fischer (or maybe Moeketsi Raselimo) [[WG211/M25Fischer| Learning Lexical Structure of Black-Box Systems via Repeated String Edit Operations]]
* Cezary Kaliszyk
* Ohad Kammar [[WG211/M25Kammar| Intrinsically typed and well-scoped SMTLIB FFI bindings with modular abstract syntax trees (MAST)]]
* Julia Lawall TBD
* Yuito Murase and Atsushi Igarashi [[WG211/M25Murase| Refined^2 Environment Classifiers]]
* Ulrik Pagh Schultz Lundquist [[WG211/M25Lundquist| The E-CoRe Project: Energy-efficient Computing via Reversibility]]
* Chung-chieh Shan
* Friedrich Steimann "Relative Multiplication of Infinite Relations"
* Michel Steuwer
* Jeremy Yallop [[WG211/M25Yallop| Frex: Dependently Typed Algebraic Simplification]]
* Eric Van Wyk TBD

== Travel ==

Note that the meeting will be in the southern Summer, just before the local holiday season starts in earnest, and Stellenbosch (and all of South Africa) will be getting busy, so arrange your flights and accommodation early.

==== Visa Information ====

Visitors from [http://en.wikipedia.org/wiki/Visa_policy_of_South_Africa most EU countries, US, Canada, Japan, Australia and most of South America] don't need a visa to visit South Africa. The complete (official) list is available at the [https://www.dha.gov.za/index.php/countries-exempt-from-sa-visas Department of Home Affairs]. Please contact [mailto:bfischer@sun.ac.za Bernd Fischer] if you need a visa to visit South Africa; please note that applications can take substantial amounts of time to get processed (although the backlog has been cleaned up after the last election...)

==== Vaccinations and Prophylaxis ====

South Africa requires yellow fever vaccinations for travelers arriving from a [https://www.southafrica.net/gl/en/travel/article/yellow-fever-entry-requirements risk area]; this includes most of South America and Central Africa, but excludes Europe, North America, Asia, and Oceania. You should probably have up-to-date standard vaccinations (such as tetanus) as you would have for travel in Europe or North America. Malaria prophylaxis is only required if you go to Kruger National Park or Victoria Falls.

The medical system is very good around Stellenbosch, but sometimes less so in other parts of the country. Check with your (travel) insurance whether they cover your trip.

==== Getting to Stellenbosch ====

The closest airport to Stellenbosch is [https://en.wikipedia.org/wiki/Cape_Town_International_Airport Cape Town International (CPT / FACT)]. There are direct flights from London (Virgin, BA), Amsterdam (KLM), Paris (Air France), Frankfurt (Condor, Lufthansa), Munich (Lufthansa), Zuerich (Edelweiss), Istanbul (Turkish Airlines), Doha (Qatar Airways), Dubai (Emirates), Addis Ababa (Ethiopian), Washington (United), Newark (United), Atlanta (Delta), and Singapore (Singapore Airlines). Note that some of these flights are seasonal and operate only during the southern Summer, so they might not show up yet. There are also regional connections to many places in southern Africa (e.g., Windhoek).

Further connections (e.g., from India, East Asia, Australia, or South America) are available with a transfer in Johannesburg. I recommend to fly into Cape Town, if feasible, because the transfer in Johannesburg requires you to clear immigration and customs (like in the US), which can be a bit unpredictable.

Flight prices vary of course wildly. I have recently paid anything between EUR 700 and 1200 for a Germany round trip, and EUR 1500 for a California round trip.

CPT is about 35km from Stellenbosch; there is no public transport, but Uber is widely available, cheap (< EUR 20 to Stellenbosch), and I always take it. Please be aware that taxi touts will try to talk you into a metered taxi as soon as you leave customs; I always politely ignore them.

If you prefer a pre-booked airport shuttle, try:
* [https://bettinashuttle.co.za/ Bettina's]
* [http://www.shuttleup.co.za/ Shuttle Up]

Stellenbosch is small and easily navigable by foot, and the venue is in walking distance to most hotels and B&Bs. You won't need a rental car unless you are planning to go on a road-trip before or after the conference. There is no public transport in Stellenbosch; do *not* take the train to Cape Town, or a minibus taxi.

==== Accommodation ====

Stellenbosch does not have big corporate hotels but offers a wide variety of different smaller accommodation options. Most centrally located B&Bs (look for the "Stellenbosch Central" or "Mostertsdrift" areas) will be in the range from EUR 80 to EUR 150 per night; there are also Airbnb-style accommodations but they tend to be more in the suburbs, and are not necessarily cheaper. Many wine farms offer luxury accommodation, but they are typically out of town and require a rental car.

Below are a number of guest houses covering different price ranges. Note that I haven't stayed in any of these... Please make your own arrangements and please note that places begin to fill up.

'''Between Stias and the town center''':
* [https://avenuesguesthouse.co.za/ Avenues Guesthouse], 32 Die Laan
* [https://beauclair-guest-cottage.hotels-of-stellenbosch.com/en/ Beauclair Guest Cottage], 1 Coetzenburg Road
* [https://www.bonneesperance.com/ Bonne Esperance], corner of Neethling and Van Riebeeck
* [https://caledon-villa.hotels-of-stellenbosch.com/en/ Caledon Villa], 7 Neethling Street
* [https://www.dehaasliving.co.za/die-laan-2/ De Haas Luxury Living - Die Laan], 2 Die Laan
* [https://www.dehaasliving.co.za/die-laan-40/ De Haas Luxury Living - Die Laan 40], 40 Die Laan
* [https://www.evergreenmanor.co.za/ Evergreen Manor], 11 Murray Street
* [https://koloniestuin.co.za/ Kolonie's Tuin], 22 Die Laan
* [https://www.laanhof.co.za/ Laanhof], 28 Die Laan (self-catering)
* [https://www.lifeandleisure.co.za/ Life & Leisure], 20 Van Riebeeck St
* [https://www.middedorp.com/ Middedorp Manor], 14 Neethling Street
* [https://www.minseriecollection.co.za/ Minserie Collection], Minserie Street (self-catering)
* [https://thelivingjourneycollection.co.za/river-manor/ River Manor], 6-8 Die Laan
* [https://www.roosenwijn.co.za/ Roosenwijn Guesthouse], 14 Van Riebeeck Street
* [https://thelivingjourneycollection.co.za/river-manor/ De Haas Luxury Living - Villa Grande], 1 Keeroom Street

'''Mostertsdrift''' (east of Stias):
* [https://www.5-seasons.co.za/ 5 Seasons Guesthouse], 60 Van Der Stel Street
* [https://lanzerac.co.za/ Lanzerac Wine Estate], Lanzerac Road (wine estate in walking distance from Stias)
* [https://www.stellenboschmanor.com/ Stellenbosch Manor], 2 Van Der Stel Street
* [https://summerwood.co.za/ Summerwood Guest House], 28 Jonkershoek Road
* [https://vanderstelmanor.com/ Van Der Stel Manor], 64 Van Der Stel Street

'''Town center''':
* [https://www.batavia-stellenbosch.co.za/ Batavia Boutique Hotel], 12 Louw Street
* [https://coopmanhuijs.co.za/ Coopmanhuijs Boutique Hotel & Spa], 33 Church Stree
* [https://www.eendracht-hotel.com/ Eendracht Hotel & Self Catering], 160 Drop Street
* [https://www.justjoey.co.za/ Just Joey Lodge], 13 Noordwal-Wes
* [https://stellenboschhotel.co.za/ Stellenbosch Hotel], corner of Dorp & Andringa

==== Security ====

South Africa has a reputation as an unsafe country but most crimes happen in township areas, and the center of Stellenbosch is generally safe; walking around town, or from town to the guesthouses in Mostertsdrift is fine, even after dinner. However, there are a few things to keep in mind:
* Do not flash your valuables (phone, wallet, camera) in public.
* Do not hand over your ATM/credit card - servers will bring a machine to your table (or will ask you to pay at the counter); if you withdraw money from an ATM, check that nobody is lurking around, and do not accept "help" from people.
* Do '''not''' walk or drive into any township (in Stellenbosch, that means Kayamandi and Cloetesville); if you are interested, you can book guided tours.
* Do '''not''' take the train between Cape Town and Stellenbosch (or trains around Cape Town).

==== Weather ====

Early December is late spring in South Africa. The weather in Stellenbosch ''should'' be nice - the average day-time highs are around 25C, night-time lows around 15C, and it ''should'' be dry. However, there are chances of an early heat wave, with temperatures above 30C, or (fortunately less likely) a late rain front with temperatures dropping by 5-10 degrees.

==== Pre- / post-meeting excursions ====

Here are a few ideas if you are planning to spend a few extra days in Stellenbosch or travel around the country:
* Spend the weekend in Cape Town and explore the city - Table Mountain is certainly a prime target. You could also go to Kirstenbosch Botanical Garden (although the prime bloom will be over then), and even climb Table Mountain from there (although this could be hot and strenuous that time of the year). Cape Town has quite a lot of night life, especially on the weekend.
* Explore the Stellenbosch surroundings. For this, you should probably get a rental car. There are literally hundreds of wine farms in the surroundings, if you want to go for a tasting. The Paarl Taal Monument (monument to the Afrikaans language) is an interesting cultural experience, and you can go on to the Paarl rock (large granite Boulder). Franschhoeck is a another cute town.
* Get out to the Cederberg Mountains - a nice mountainous area about 2-3hours north of Cape Town, with nice mountain walks (Wolfberg Cracks, some caves). You could stay at Clanwilliam, or look for a place in the mountain reserve (look for Algeria). The roads are mostly dirt (ie unpaved) but we have driven them in a Polo...
* Hike the Bosmanskloof Traverse (either as an overnight hike, or as a day-hike), staying in McGregor or Grayton.
* Go to Calitzdorp for Port tasting, Oudtshoorn for the ostriches (and the very tourist-trappy Cango Caves, a huge limestone cave), and drive some of the old Mountain passes, like [http://en.wikipedia.org/wiki/Swartberg_Pass Swartbergpass] into Prince Albert, a quaint Karoo town, and "poorts" (i.e., mountain notches), like [https://en.wikipedia.org/wiki/Seweweekspoort| Seweweekspoort].
* Go shark cage diving in Struisbaai.

Except for the Cape Town weekend, most trips will require a rental car. You can get an uber or a dedicated driver for a wine tasting tour, which is probably a smart idea in the first place...

'''Safaris.'''
There are no lions running around in Stellenbosch ;-). The closest ones are at the [http://www.lionrescue.org.za/ Drakenstein Lion Park], which is basically a retirement home for lions. There are a few private game reserves within two to three hours drive of Stellenbosch (e.g., [https://grgamelodge.co.za/ Garden Route Game Lodge] or [http://www.sanbona.com/propertydefault.asp?MicroSiteID=3 Sanbona]), but they are not cheap. The closest National Parks with substantial wildlife are [http://www.sanparks.co.za/parks/mountain_zebra/ Mountain Zebra NP] and [http://www.sanparks.org/parks/addo/ Addo Elephant NP] (about 8-10hrs drive from Stellenbosch, but Addo is quite close to Port Elizabeth, which is one hour by plane from Cape Town). If you plan to visit [http://www.sanparks.org/parks/kruger/ Krueger NP] you should probably fly with a stop-over in Johannesburg, and plan on at least four extra days.

==== Arrivals and departures of attendants ====

* Friedrich will arrive on Monday morning (Condor flight DE2290, ETA 10:45 am) and leave on Friday evening (DE2291 at 7:50 pm); will stay at Evergreen Manor.
* Julia will arrive on Monday morning at 5:50am (Air France from Paris) and leave on the following Monday morning at 7:55am; staying at The Avenues Guest House.

WG211/M25Schedule

2025-08-11T06:26:29Z

Sebastian: /* Members attending */

WG211/M25Schedule

2025-08-11T06:23:56Z

Sebastian: /* Guests and Observers */

WG211/M24Erdweg

2024-11-20T16:06:20Z

Sebastian: Created page with "Differential operators map input changes to output changes, which can be used to implement efficient incremental computations. For example, differential operators for relation..."

Differential operators map input changes to output changes, which can be used to implement efficient incremental computations. For example, differential operators for relational algebra excel at supporting live view maintenance in database systems. However, there are no guidelines for developing new differential operators and there is no formal framework for proving them correct. We develop a formal framework in Coq for developing and verifying efficient differential operators. Our framework is based on a flexible theory of change structures that we present. A key novelty of our framework is that it allows differential operators to declare and use custom state, which is crucial for incremental performance. We demonstrate that our framework can be used to design new differential operators, and also model some of the most sophisticated existing operators: database join and Datalog aggregation.

WG211/M24Schedule

2024-11-20T16:03:50Z

Sebastian: /* Talks */

= IFIP Working Group 2.11, Twenty-fourth Meeting =

== December 3rd (Tues) - 6th (Fri) in Edinburgh, Scotland, UK ==

The meeting will be hosted by [https://www.denotational.co.uk/ Ohad Kammar], who will write in the first person in the remainder. If you want to know anything, please email me. This page is not yet finished, I'll try to add the missing information as soon as possible.

The meeting will last 3.5 days; the first three days (Tues-Thur) will
be full-day whereas the last day (Fri) will be a half-day session.

=== Venue ===

[https://www.ed.ac.uk/timetabling-examinations/timetabling/room-bookings/bookable-rooms3/room/0401_01_1.07 Althaus-Reid Room, 1.07] ([http://exhibition.div.ed.ac.uk/rooms-renamed-in-honour-of-two-inspirational-female-theologians/ named after the theologian Marcella Althaus-Reid])

New College 
School of Divinity 
The University of Edinburgh 
Central Campus 
1 Mound Place 
Edinburgh EH1 2LU

This is unfortunately '''not''' the School of Informatics, which is about 15 minutes walk south from this venue.

A [https://maps.app.goo.gl/oCXGNCb2ax68WS6B6/ Google map] with the venue, hotels, and meeting-relevant locations.

==== WiFi Access ====

* '''eduroam.''' If you have eduroam credentials, you may use them to access the eduroam network while at Edinburgh.

* '''guest account.''' If you know that eduroam will not work for you, I can set you up with a guest account. Please indicate that you will definitely need a guest account in your registration form. You can always let me know after registration whether you need one, including during the meeting. Guests must abide by the [https://vpnreg.ucs.ed.ac.uk/admin/compregs.pdf computing regulations].

* '''Visit-Ed.''' If eduroam does not work for you and you don't have a guest account, you can try using the [https://www.ed.ac.uk/information-services/computing/desktop-personal/wifi-networking/guest-alumni-wifi-access Visit-Ed service] described in the middle of that page. It requires registration by Facebook, LinkedIn, WhatsApp, or text message (international numbers included).

==== Workspace ====

A quiet area for shared use is available in the [https://www.ed.ac.uk/timetabling-examinations/timetabling/room-bookings/bookable-rooms3/room/0401_01_1.09 Porteous Room 1.09]
(you can read more about it
[https://exhibition.div.ed.ac.uk/porteous%E2%80%AFroom/ here]) on the
same floor as the main room.

== Travel ==

=== Travel to Edinburgh ===

==== Air ====

[https://www.edinburghairport.com/ Edinburgh Airport] is located
approximately 8 miles away from the city centre.

The [https://edinburghtrams.com/ Edinburgh tram] runs from the
airport every 7 minutes, the last tram from the airport leaves after
22:30 (see tram webpage).

The [https://airlink100.co.uk/ Airlink bus] (service 100) runs
between the airport and the city centre, reaching Waverley Bridge
railway station in 25 minutes. The route to and from the airport runs
24 hours a day every 10 minutes approximately during the day.

Most advance hire taxi companies will offer an airport pick-up
service. [https://www.taxis-edinburgh.co.uk/ Here's one], but any will
do. There's also a taxi hailing stand at the airport, follow the signs.

You can also fly into another main UK city and continue to Edinburgh by [[#Train|train]].

==== Train ====

Edinburgh is well-connected to most other main UK cities. There are a
few faster trains from London (about 4h25min) every day. You can use [https://www.nationalrail.co.uk/ National Rail] to plan your trip and link you to the appropriate provider.

I have enjoyed taking the Eurostar from the main continent to London. There is also the [https://www.sleeper.scot/ Caledonian Sleeper] that can get you to Edinburgh or London by 7am very slowly overnight.

=== Travel around Edinburgh ===

Edinburgh is somewhat hilly and the venue is located [https://upload.wikimedia.org/wikipedia/commons/f/ff/The_Mound%2C_Edinburgh%2C_18_September_2014.jpg up a slope].
If that is not a problem, then Edinburgh is quite walkable.

Public transportation is available. Check out [https://transportforedinburgh.com/ Transport for Edinburgh] for all the details.

* Buses. [https://www.lothianbuses.com/ Lothian buses] operates many of the relevant buses. You can pay contactless with a card or app and there's a capped pay program ('TapTapCap'). Here's the [https://www.lothianbuses.com/wp-content/uploads/2024/09/Network_Map_240908.pdf map], but I usually use Google maps for directions.

* Taxis. You can usually just hail a black cab from anywhere in the centre, see their [https://www.taxis-edinburgh.co.uk/ webpage] for advance bookings. Your favourite search engine will provide other taxi companies.

* Tram. The [https://edinburghtrams.com/ Edinburgh tram] stops fairly close to the venue, so can be an easy way to the venue.

* Uber operates in Edinburgh.

== Accommodation ==

The venue is located quite centrally, with many hotels nearby. Here are some 4-star and 3-star suggestions nearby, but you'll probably find something charming by your own (just watch out for scams). The tram and buses make it easy to also stay somewhere away from the centre and commute in if you prefer.

Hotel suggestions:
* [https://www.apexhotels.co.uk/destinations/edinburgh/apex-grassmarket-hotel/ Apex Grassmarket Hotel]. Main suggestion, slightly-up-and-steep-downhill from the venue. We have a 10% discount code, which I will email once I have it. '''Note:''' There is a slightly more full Apex hotel on the same street which I listed before, so if you want to be in the suggested hotel, make sure you're in the correct one.
* [https://www.motel-one.com/en/hotels/edinburgh/hotel-edinburgh-royal/ Motel One Edinburgh Royal]. A cheaper option, steep downhill from the venue.
* [https://www.scotsmanhotel.co.uk/ Scotsman Hotel]. A more expensive option, slightly-up-and-moderate-downhill from the venue.

== Weather ==

Edinburgh has temperate (and temperamental) climate, and in December it will likely be close to zero degrees centrigade, typically above. It will be windy, and potentially rainy, so make sure you dress appropriately. Locals wear waterproof/resistant clothes. Umbrellas tend to be rather useless due to the wind, one typically recognises the tourists by their futile struggles to turn inside-out umbrellas
while getting soaked.

The days are quite short in December, and you might be able to catch
the sunrise heading into the venue in the morning. I recommend
avoiding missing most of the daylight completely, e.g., make sure you go
for a short walk outside during the lunch break.

== Tourism ==

Edinburgh offers many tourist attractions and museums, and many are located centrally and close to the venue. Entrance to museums and galleries is free. Entrance to some exhibitions in the museum or gallery will require buying a separate ticket.

The meeting takes place just after [https://www.visitscotland.com/things-to-do/events/st-andrews-day Saint Andrew's Day] weekend, and Monday will be a public holiday in Scotland.
That should not affect travel, although the airport and railway might be busier than usual.

[https://www.historicenvironment.scot/about-us/news/st-andrews-day-ticket-giveaway/ Historic Environment Scotland] offer free tickets to visit some Historic Scotland attractions on Saint Andrew's day, such as the Edinburgh Castle. Registration for [https://www.historicenvironment.scot/ticket-giveaway/ free tourism tickets] opens Tuesday 12 November 10am UK time until Thursday 28 November.

If you go to the Castle, try to get there before 1pm to see them fire the Cannon.

Very near the venue is Scott Monument which you can climb, for a fee,
during the day for a stunning view. There will be a German Christmas
Market nearby I believe.

There are several hills within the city and you can easily climb up. The easiest (and closest to the venue) is [https://ewh.org.uk/calton-hill/ Carlton Hill] and has a road and steps leading all the way up.

[https://www.geolsoc.org.uk/GeositesArthursSeat Arthur's Seat and the Salisbury Crags] are most visible from the centre. It takes about 1.5 hours roundtrip to get to the top. The grass can be slippery after a rain, and people can slip to their death, so wear good shoes and only climb during the day.

You can sometimes take a daytrip on a guided tour to the highlands or a whisky distillery. If you have the time, I recommend spending a few days in the former, and maybe visiting some of the latter.

I'll try to add more stuff here, especially if people send me recommendations or ask questions.

== Registration ==

Working on it, I'll put up more details soon.

== Attendance ==
(Alphabetical by last name please)

* Guillaume Allais
* Nada Amin
* Sandrine Blazy
* Edwin Brady
* Jacques Carette
* Sebastian Erdweg
* Jeremy Gibbons
* Kevin Hammond
* James McKinna
* Ohad Kammar
* Paul Kelly (on 5-6 only)
* Andras Kovacs
* Lindsey Kuper
* Julia Lawall
* Ralf Lämmel
* Sam Lindley
* Peter Mosses
* Christoph Reichenbach
* Tiark Rompf
* Sven-Bodo Scholz
* Amir Shaikhha
* Friedrich Steimann
* Tijs van der Storm
* Jeremy Yallop

=== Local Observers ===

== Talks ==

See below for the schedule (but note that the actual scheduling of talks will not be available until the meeting starts). Members: please add yourself and your topic, alphabetically ordered by surname:

* Edwin Brady [[WG211/M24Brady | "Normalisation by Compilation": Typechecking Dependent Types via the Scheme Runtime ]]
* Jacques Carette [[WG211/M24Carette | Partial Evaluation meets Denotational Semantics ]]
* Sebastian Erdweg [[WG211/M24Erdweg | Stateful Differential Operators for Incremental Computing ]]
* Kevin Hammond [[WG211/M24Hammond | Using Formal Methods at Scale in the Delivery of a High Assurance Distributed System: the Cardano Blockchain Implementation in Haskell ]]
* Jeremy Gibbons [[WG211/M24Gibbons | Continuation−Passing Style‚ Defunctionalization‚ Accumulations‚ and Associativity ]]
* Tiark Rompf [[WG211/M24Rompf | Rhyme: A Data-Centric Multi-Paradigm Query Language ]]
* Friedrich Steimann [[ WG211/M24Steimann | A really old new metatheory of software languages ]]

We will follow our usual format of interactive talks with an active audience, using a chess clock for timing, as follows. For each talk the speaker and the audience each get at most 25 minutes. The audience does not have to wait until the end of a talk to ask questions; interaction and discussion is encouraged. (But experience from previous meetings shows that it is useful to let the speaker at least finish the introduction before interrupting.) To ensure fairness, administration of the time used by each party is done using a chess clock. Operation of the clock rotates among participants. Both speaker and audience are expected to contribute to make talks and discussions engaging, interesting, and useful. Therefore, we observe a policy of no use of electronic devices during talks (other than the device the speaker uses to present slides). Bring paper and pen for making notes.

== Program / schedule ==

=== Scientific program ===

To be determined.

Tuesday, December 3

* 8:45 - 9:00 Welcome
* <<TBD>> - <<TBD>> <n> talks
** <<TBD>> - <<TBD>>
* <<TBD>> - <<TBD>> Break
* <<TBD>> - <<TBD>> <n> talks
** <<TBD>> - <<TBD>>
* <<TBD>> - <<TBD>> Lunch
* <<TBD>> - <<TBD>> <n> talks
** <<TBD>> - <<TBD>>
* <<TBD>> - <<TBD>>

Wednesday, December 4

* 9:00 - <<TBD>> <n> talks
** <<TBD>> - <<TBD>>
* <<TBD>> - <<TBD>> Break
* <<TBD>> - <<TBD>> <n> talks
** <<TBD>> - <<TBD>>
* <<TBD>> - <<TBD>> Lunch
* <<TBD>> - <<TBD>> <n> talks
** <<TBD>> - <<TBD>>
* <<TBD>> - <<TBD>>

Thursday, December 5

* 9:00 - <<TBD>> <n> talks
** <<TBD>> - <<TBD>>
* <<TBD>> - <<TBD>> Break
* <<TBD>> - <<TBD>> <n> talks
** <<TBD>> - <<TBD>>
* <<TBD>> - <<TBD>> Lunch
* <<TBD>> - <<TBD>> <n> talks
** <<TBD>> - <<TBD>>
* <<TBD>> - <<TBD>>

Friday, December 6

* 9:00 - <<TBD>> <<n>> talks
** <<TBD>>-<<TBD>> <<TBD>>
* <<TBD>> - <<TBD>> Break
* <<TBD>> - <<TBD>> 1 talk
* <<TBD>> Lunch

=== Social events ===

To be determined.