Bonn Lean seminar, summer semester 2026

This is the repository for the advanced Lean seminar at university Bonn.

Prerequisites. Lean knowledge at the level of e.g. the lecture "Topics in Computer-assisted Mathematics" in WiSe25/26 (course page). The lecture will be offered again next winter; if you have not used Lean before, I recommend you take it first. If you have used Lean, but are unsure about your knowledge, feel free to write me an email (rothgang at math.uni-bonn.de).

Initial meeting. Thursday, February 12 at 10.15 (room 0.011).

Regular seminar time and place: Tuesdays, 14.15 to 15.45 (room N.008 --- in the Neubau building behind the main mathematics building)

Outline and topics: see here

Tentative schedule

Some details are subject to change: a few talks need to be scheduled, for example.

• April 14. equality, transparency and all that (Fridolin)
• April 21. unification (Max)
• April 28. typeclass inference, part 1 (Jasper)
• May 5. typeclass inference, part 2 (Alex)
• May 12. no seminar
• ~~**May 19.**~~will be rescheduled simp, simp sets and simp normal forms (Vivek)
• May 26. no seminar (holiday)
• June 2. integrals within integrals and the Sobolev inequality (Felix)
• June 9. the mathlib contribution process (Ruth)
• June 16. the gcongr tactic (Pascal)
• June 23. no seminar
• June 30. no seminar
• July 7. the grind tactic (Hannah)
• July 14. Doob's martingale convergence theorem (Shuhan)
• July 21. homological algebra and homology (Abel)

Not yet scheduled are talks by

• Johannes on verbose lean (and perhaps waterproof)
• Yannik on the aesop tactic
• Pan on the positivity tactic
• Pablo about the flypitch project and model theory
• Evgeniya about semantic engines and how they work
• Arend about qq, metaprogramming and ring

There will be a poll for finding suitable dates soon.