PyPy.js: What? How? Why?

on YouTube ↗26m

" summary

Claims a working in‑browser Python VM by PyPy interpreter compiled into javascript and retargeting its JIT to emit asmjs. Benchmarks show native CPython ~70–80k pistones per second, cold PyPy.js ~30–40k, warmed JIT ~140000 pistones per second. Exposes a coarse JS API and a js module to interoperate with the page. Practical issues remain: large payloads (around 15 megabytes download), garbage collection and Firefox edge cases, but core approach demonstrably runs and optimizes at surprising speed.

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" chapters (4)

1. 0:00Start
2. 3:02The Web is worth Keeping
3. 21:01You're gonna have a bad time
4. 22:54IPython Notebook

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