The previous canvas was built at a time when most sites were desktop-first and layouts were largely static. As projects grew more complex — dense breakpoint stacks, deeply nested grids, scroll-linked animations — the rendering pipeline started to show its age. Frames would repaint unexpectedly, selection latency crept up, and large pages occasionally stuttered during drag operations.

A single-pass layout engine

The new layout engine processes the full constraint tree in a single pass before committing to the DOM. This means layout shifts that used to cascade across sibling nodes are now resolved entirely off-screen. In practical terms: moving a deeply nested frame no longer causes unrelated sections to flicker, and breakpoint switching is instantaneous even on pages with hundreds of nodes.

Measured impact

Across a test set of 50 real-world projects, average frame repaint time dropped by 64%. Selection responsiveness improved by 3× on pages with more than 200 layers. Memory usage during publish also decreased meaningfully — the new renderer holds fewer intermediate paint buffers, which matters especially on lower-powered machines. We’ll continue profiling edge cases in the weeks ahead and ship incremental fixes as we identify them.