Here are some odds and ends, consisting mainly of notes on my own research, as well as some seminar talks where I try to understand a new piece of mathematics. I now try to skip to blackboard talks, so speak to me in person to get the notes for those if you are interested.

- A talk on gluing curves along their torsion, given at AGC2T 2021 at the CIRM in Luminy. Notes available here.
- A talk on isogenous (non-)hyperelliptic CM Jacobians, given at the Oberseminar at the Institute of Algebra and Number Theory at Ulm University. Notes available here.
- A talk on arithmetic Fuchsian groups, given at the GADEPs Seminar at the Instituto Nacional de Matemática Pura e Aplicada.
- A talk on endomorphism verification given at the Institute for Computational and Experimental Research in Mathematics at Brown University. Notes available here.
- A talk on reconstructing quartics from their invariants, given at the Banff International Research Station.
- Notes for a course on algebraic number theory.
- En français mutilé : notes sur les préliminaires et le deuxième chapitre du livre Geometric Invariant Theory de Mumford (écrits pour un groupe de travail à l'IRMAR organisé par David Lubicz).
- Notes on algebraic groups from the 2010 Leiden Obstructions Seminar.
- Slides for an Intercity Seminar talk on explicit equations for (1;e)-curves, given in 2009.
- Notes on a-transformations for the 2009 Seminar on Complex Multiplication in Leiden.
- Slides for a talk on Humbert surfaces and Shimura curves in a 2008 Intercity Seminar.
- Notes on Drinfel'd-Vladut and modular curves, from the 2008 Leiden Seminar on Rational Points on Curves over Finite Fields.
- Two notes from the 2007 Seminar on Moduli Spaces and Modular Forms in Leiden: one on dimension formulas for spaces of modular forms and one on explicit moduli spaces.
- My master's thesis. Caveat lector: there are rather serious calculatory and conceptual mistakes in there, which I should fix.