I have a lot of pending things to get to, which I hopefully do by the end of the month, including some more elaborate blog posts.
For now though, this is a puzzle.
Draw a non-intersecting loop through the centers of some cells which passes through each region exactly once. A number in a region represents how many cells in the region are visited by the loop. Orthogonally adjacent cells across a region border may not both be unused. The black cell just means it’s a hollow, I.e., not part of the grid.