July 6, 2020. Flat connections and the fundamental group (PDF version)
June 14, 2020. The cocycle approach to algebraic topology (PDF version)
May 9, 2020. Torsors and cocycles (PDF version)
May 2, 2020. A first idea of the cohomology of sheaves (PDF version)
(For any comments, feel free to message me at guille@guillegallego.xyz).