I'd never written these puzzles before. I've solved enough though. In my design I tried to form the solution form a few strategically placed digits. I think this solve worked out well, but I could probably design much trickier puzzles in this genre. It's sometimes just hard to keep track of everything. It's easy to run into no solution moments.
Place the number 1-3 trice in each row and column (1-2 twice in the example). Digits in grey cells can't share an edge with an equal number. Digits in white cells must share an edge with at least one equal number. All grey cells are given.