Logic Masters Deutschland e.V.

EDIT: I've added one small clue, to smooth out the ending of the puzzle. I think I lost a bit of logic at some point and didn't realize it. Sorry about that!

The grid is toroidal, which means for the purpose of clues, rows 1/9 and columns 1/9 are adjacent. Clues outside the grid give the sums of the digits that are orthogonally adjacent to either the 1 or 9 in the row or column. The solver must determine which clues are for ones, and which are for nines. Where two clues appear, they give the sums for both the 1 and 9, and the order in which the sums appear (left to right in a row, top to bottom in a column, sums that wrap around the edge are ordered according to where the 1/9 appear). Some clues are replaced with question marks, which represent unknown numbers. Inequality signs give the relationship between two clues or cells. Digits in cages sum to the number in the upper left corner.

f-puzzles link

I have more puzzles on my website