I refactored Exodra's DOM build walk to allocate less per node. It came out 11% slower. Here is exactly why — with the measurements that caught it and the one-line change that fixed it.

Every reactive framework faces the same dilemma: how to handle different types of properties efficiently. Most frameworks choose developer convenience over performance. We chose performance.

Exodra moved from a legacy per-node bookkeeping model to a WeakMap-based core. This post is about why that's a better design — less work per node, GC-driven cleanup, and cache-friendly lookups. It is deliberately light on "X% faster" numbers, because the honest, reproducible timings come from npm run bench, not prose.