Share one compiler + Python runtime across all docs pages - #2
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…background The runnable-block worker is now a SharedWorker where supported (dedicated per-page worker as fallback, with in-flight replay if shared mode errors), so open tabs and the playground share a single live compiler and Pyodide instance; runs serialize inside the worker since pages share one interpreter. A SharedWorker still dies with its last page, so a same-tab navigation restarts it: for visitors who have used Run before (a localStorage flag), every page now warms the worker in the background at load, and the runtime is ready by the time they click. The docs widget also compiles inside the worker now, so lesson pages load no WASM on the main thread at all. Measured on lesson pages: first-ever run ~6.6s with the honest progress message; after a same-tab navigation ~1.0s (was ~6.3s); second tab ~0.6s; same-page rerun ~0.8s.
simontreanor
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Jul 16, 2026
…background (#2) The runnable-block worker is now a SharedWorker where supported (dedicated per-page worker as fallback, with in-flight replay if shared mode errors), so open tabs and the playground share a single live compiler and Pyodide instance; runs serialize inside the worker since pages share one interpreter. A SharedWorker still dies with its last page, so a same-tab navigation restarts it: for visitors who have used Run before (a localStorage flag), every page now warms the worker in the background at load, and the runtime is ready by the time they click. The docs widget also compiles inside the worker now, so lesson pages load no WASM on the main thread at all. Measured on lesson pages: first-ever run ~6.6s with the honest progress message; after a same-tab navigation ~1.0s (was ~6.3s); second tab ~0.6s; same-page rerun ~0.8s.
This was referenced Jul 31, 2026
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SharedWorker-backed runner (with per-page fallback), background warm-up for returning users, worker-side compilation for docs pages. Same-tab navigation Run time drops from ~6.3s to ~1.0s; cross-tab to ~0.6s.