Retain every finite observation, datum, color, position and bucket identity in the TanStack scene. Above 2048 points, paint dots directly at device pixel ratio inside the SVG mark group. Keep axes and focus SVG and sparse plots native SVG. Paint the full surface to preserve endpoint circles.

Controlled renderer microbenchmark, 9870 marks: native SVG render 145 -> 29 ms, presentation 229 -> 87.5 ms, DOM 9906 -> 38 nodes. Default dashboard checkpoint: all charts 3133.7 -> 2817.0 ms and heap 21.1 -> 19.0 MiB. Some exploratory checkpoint validation overlapped; the uncontended final benchmark is the shipping comparison. No sampling or aggregation.

Checkpoint measurements above predate the final QA lifecycle/coverage fixes and are not isolated shipping effects. Combined shipping benchmark: 477.2/2934.3 ms default visible/all charts, 114 ms observed initial TBT, 18.2 MiB retained heap and 191.1 KiB gzip JS. Original baseline: 509.1/3258.9 ms, 130 ms, 18.3 MiB, 228.1 KiB. Layer 3: 569.3/4271.3 ms, 159 ms, 29.9 MiB, 202.4 KiB. Baseline dates, five API runs, three fresh contexts per page and one warmup; no concurrent QA/build/dev work. Shipping artifacts: /tmp/atlantis-frontend-overhaul/perf/layer4-shipping/results.json. Full gates pass with 220 web and 70 e2e tests.