{"slug": "profiling-web-edit-with-python-3-15-flame-graphs-and-source-heatmaps", "title": "Profiling web-edit with Python 3.15: flame graphs and source heatmaps", "summary": "Simon Willison profiled his web-edit app using the new sampling profiler in Python 3.15, directing GPT-6 Astra Extra High in Codex to run the profiler and produce a flame graph and source heatmap demo. The resulting artifacts, a flame graph and a heatmap, are published on GitHub Pages under Willison's research repository. The exercise demonstrates the Python 3.15 profiler's flame graph and source heatmap output on a real PyPI application.", "body_md": "**Research:** [Profiling web-edit with Python 3.15: flame graphs and source heatmaps](https://github.com/simonw/research/tree/main/python-3-15-web-edit-profiling#readme)\n\nI put the [new Python 3.15 profiler](https://simonwillison.net/2026/Oct/12/python-3-15/#a-sampling-profiler) through its paces by having GPT-6 Astra Extra High in Codex run it against my new [web-edit app](https://simonwillison.net/2026/Oct/12/web-edit/):\n\n`I need a Python 3.15 flame graph and heatmap demo of the \"web-edit\" app from PyPI - research first then make me those demos`\n\nHere's the resulting example [flame graph](https://simonw.github.io/research/python-3-15-web-edit-profiling/artifacts/flamegraph.html) and [heatmap](https://simonw.github.io/research/python-3-15-web-edit-profiling/artifacts/heatmap/index.html).", "url": "https://wpnews.pro/news/profiling-web-edit-with-python-3-15-flame-graphs-and-source-heatmaps", "canonical_source": "https://simonwillison.net/2026/Oct/12/python-3-15-web-edit-profiling/", "published_at": "2026-10-12 16:58:00+00:00", "updated_at": "2026-10-15 05:17:53.211922+00:00", "lang": "en", "topics": ["developer-tools", "ai-tools"], "entities": ["Simon Willison", "Python 3.15", "GPT-6 Astra Extra High", "Codex", "web-edit", "PyPI", "GitHub Pages"], "also_reported_by": [], "alternates": {"html": "https://wpnews.pro/news/profiling-web-edit-with-python-3-15-flame-graphs-and-source-heatmaps", "markdown": "https://wpnews.pro/news/profiling-web-edit-with-python-3-15-flame-graphs-and-source-heatmaps.md", "text": "https://wpnews.pro/news/profiling-web-edit-with-python-3-15-flame-graphs-and-source-heatmaps.txt", "jsonld": "https://wpnews.pro/news/profiling-web-edit-with-python-3-15-flame-graphs-and-source-heatmaps.jsonld"}}