Research-level output at startup velocity.https://spoorendonk.dk/https://spoorendonk.dk/writing/pull-instead-of-push/https://spoorendonk.dk/writing/pull-instead-of-push/The bottleneck in a routing solver is usually one inner loop. Turning it around, so that work is gathered rather than handed out, made it about 18× faster on hard instances, and 274× on the best case.Tue, 08 Sep 2026 00:00:00 GMThttps://spoorendonk.dk/writing/the-1993-answer-was-right-until-it-wasnt/https://spoorendonk.dk/writing/the-1993-answer-was-right-until-it-wasnt/A paper from 1993 measured two ways of solving multi-commodity flow and picked a winner. Thirty-two years later the answer flipped, not because anyone found a mistake, but because the machines got big enough to change what the bottleneck was.Tue, 08 Sep 2026 00:00:00 GMT