Syness Studios — Writing https://syness.io/blog/ A one-person software studio shipping small, polished consumer apps. en X-wing: one digit, two rows, two columns https://syness.io/blog/x-wing/ https://syness.io/blog/x-wing/ Tue, 11 Aug 2026 00:00:00 GMT The sixth technique, and the first one that spans the whole board rather than a single region. Sudoku techniques, in the order worth learning them https://syness.io/blog/sudoku-techniques/ https://syness.io/blog/sudoku-techniques/ Tue, 11 Aug 2026 00:00:00 GMT The ladder is seven techniques long. The first three finish almost every Easy puzzle in our app; Hard needs more than all seven. Naked pairs: two squares that own two numbers https://syness.io/blog/naked-pairs/ https://syness.io/blog/naked-pairs/ Tue, 11 Aug 2026 00:00:00 GMT The fourth technique. Two squares agree on the same two candidates, and everything around them gets smaller. How to play Sudoku: the rules, and your first move https://syness.io/blog/how-to-play-sudoku/ https://syness.io/blog/how-to-play-sudoku/ Tue, 11 Aug 2026 00:00:00 GMT One of each digit per row, column and box. That is the entire rule set — the rest is what to do with it. Hidden pairs: two numbers that own two squares https://syness.io/blog/hidden-pairs/ https://syness.io/blog/hidden-pairs/ Tue, 11 Aug 2026 00:00:00 GMT The fifth technique, and the one people skip. It looks like clutter until you know what you're looking at. Pointing pairs: reading a box like a sentence https://syness.io/blog/pointing-pairs/ https://syness.io/blog/pointing-pairs/ Tue, 04 Aug 2026 00:00:00 GMT The third technique, and the first one that doesn't place a number. It clears the way for the ones that do. Why our Sudoku app has no hint button https://syness.io/blog/no-hint-button/ https://syness.io/blog/no-hint-button/ Tue, 04 Aug 2026 00:00:00 GMT The feature we left out on purpose, and the line we used to decide what stays in. Naked singles: the square that can only be one number https://syness.io/blog/naked-singles/ https://syness.io/blog/naked-singles/ Tue, 04 Aug 2026 00:00:00 GMT The first real Sudoku technique, explained without the jargon — and the one habit that gets you unstuck. Hidden singles: the number with only one home https://syness.io/blog/hidden-singles/ https://syness.io/blog/hidden-singles/ Tue, 04 Aug 2026 00:00:00 GMT The second technique, and the one that gets you moving again when crossing off stops working. Stuck on a Sudoku: five kinds of stuck and what each needs https://syness.io/blog/five-kinds-of-stuck/ https://syness.io/blog/five-kinds-of-stuck/ Tue, 04 Aug 2026 00:00:00 GMT Being stuck isn't one problem. Work out which one you've got and most of them take under a minute to clear. On building a studio of one https://syness.io/blog/on-building-a-studio-of-one/ https://syness.io/blog/on-building-a-studio-of-one/ Sat, 18 Apr 2026 00:00:00 GMT What "AI factory" actually means when you're the only one in the building.