--- title: Cloudflare Python Workers are GA, but the startup tax is... description: Cloudflare Python Workers reached general availability, giving Python first-class status alongside TypeScript on the platform, with native ASGI/WSGI support... canonical: https://daily.dev/posts/cloudflare-python-workers-are-ga-but-the-startup-tax-is-real-h5uc0vknh twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Cloudflare Python Workers are GA, but the startup tax is real | daily.dev og:description: Cloudflare Python Workers reached general availability, giving Python first-class status alongside TypeScript on the platform, with native ASGI/WSGI support... og:url: https://daily.dev/posts/cloudflare-python-workers-are-ga-but-the-startup-tax-is-real-h5uc0vknh og:image: https://api.daily.dev/og/posts/h5uC0VknH.png og:image:alt: Cloudflare Python Workers are GA, but the startup tax is real og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Cloudflare Python Workers are GA, but the startup tax is real **[Trends](https://daily.dev/sources/trends)** · 2 min read · 1 upvotes · 0 comments ## Summary Cloudflare Python Workers reached general availability, giving Python first-class status alongside TypeScript on the platform, with native ASGI/WSGI support for FastAPI, Django, and Flask, plus access to D1, R2, Durable Objects, and Hyperdrive database drivers. Under the hood, CPython runs inside V8 isolates via Pyodide compiled with Emscripten, and Cloudflare pushed PEP 783 through the Python steering council to standardize cross-compiled wheels for PyPI. Despite the capability wins, early testing (including by Kent C. Dodds) found startup times noticeably slower even when warm, with no new capabilities unlocked for his use case, leading him to skip Python support for now. The launch is best suited for teams with existing Python codebases needing edge deployment or AI/ML workflows where library support outweighs cold-start speed; performance-sensitive new projects are better served by TypeScript Workers. ## Content Cloudflare shipped Python Workers to general availability this week, making Python a proper first-class citizen on their platform alongside TypeScript. The pitch is solid: run FastAPI, Django, or Flask natively via ASGI/WSGI connectors, hit D1, R2, and Durable Objects without JavaScript glue code, and use standard database drivers against PostgreSQL and MySQL through Hyperdrive. AI libraries like `openai`, `langchain`, and `mcp` work too, since Cloudflare patched their HTTP clients to route through the JS fetch API. The technical story underneath is interesting. CPython runs inside V8 isolates via Pyodide compiled with Emscripten, which is the same stack that powers Python in the browser. Cloudflare also pushed PEP 783 through the Python steering council, standardizing PyEmscripten so cross-compiled wheels can land on PyPI. That's a real contribution to the ecosystem, not just a product announcement. But here's where the reception gets complicated. Kent C. Dodds ran a quick experiment integrating Python Workers into Kody and came back with a clear verdict: "much slower to start up (even when warm) and doesn't unlock new capabilities." He's passing on Python support for now. That's the honest tension in this launch. The capability story is genuinely impressive on paper. The runtime story is less flattering. Running CPython through Emscripten inside a V8 isolate is a lot of layers, and those layers cost something at startup. For latency-sensitive workloads, that matters. Who this actually helps: teams with existing Python codebases that want edge deployment without a rewrite, or ML/AI workflows where the library ecosystem matters more than cold-start speed. If you're starting fresh and performance is a priority, TypeScript Workers still have the edge. The PEP 783 angle is probably the most underrated part of this. Getting WebAssembly-compiled Python packages into PyPI's standard distribution pipeline is a slow-burn win that'll matter more as the ecosystem grows. The GA launch is the headline; the package ecosystem work is what makes it stick long-term. ## Questions this post answers ### Are Cloudflare Python Workers ready for production use now that they're generally available? Yes, Cloudflare Python Workers reached general availability, supporting FastAPI, Django, and Flask natively via ASGI/WSGI connectors, with access to D1, R2, Durable Objects, and Hyperdrive for PostgreSQL/MySQL. AI libraries like openai, langchain, and mcp also work since their HTTP clients were patched to route through the JS fetch API. However, startup latency remains slower than TypeScript Workers, even when warm. _Weighing Python versus TypeScript for edge workers? Track real-world performance reports on daily.dev as they surface._ ### Why are Cloudflare Python Workers slower to start up than TypeScript Workers? CPython runs inside V8 isolates via Pyodide compiled with Emscripten, the same stack used for Python in the browser, adding multiple execution layers compared to native TypeScript. Kent C. Dodds tested Python Workers in Kody and found them much slower to start up even when warm, with no new capabilities unlocked, and chose to skip Python support for now. _Developers comparing cold-start tradeoffs across runtimes can follow these benchmarks on daily.dev._ ### What is PEP 783 and why does it matter for Python on Cloudflare Workers? PEP 783 is a Python steering council proposal, pushed through by Cloudflare, that standardizes PyEmscripten so cross-compiled WebAssembly wheels can be published directly to PyPI. This is described as a slow-burn ecosystem win separate from the GA launch itself, making WebAssembly-compiled Python packages easier to distribute as the ecosystem grows. _Anyone tracking Python's WebAssembly packaging story can follow ecosystem changes like this on daily.dev._ ## Similar posts on daily.dev - [Python Workers redux: fast cold starts, packages, and a uv-first workflow](https://daily.dev/posts/python-workers-redux-fast-cold-starts-packages-and-a-uv-first-workflow-3o1ezoau3) · Cloudflare · 31 upvotes · 0 comments - [Cloudflare Workflows Adds Python Support for Durable AI Pipelines](https://daily.dev/posts/cloudflare-workflows-adds-python-support-for-durable-ai-pipelines-7kkgpybvz) · InfoQ · 0 upvotes · 0 comments --- Tags: [#python](https://daily.dev/tags/python), [#serverless](https://daily.dev/tags/serverless), [#webassembly](https://daily.dev/tags/webassembly), [#cloudflare](https://daily.dev/tags/cloudflare) [View this post on daily.dev](https://daily.dev/posts/cloudflare-python-workers-are-ga-but-the-startup-tax-is-real-h5uc0vknh) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Cloudflare Python Workers are GA, but the startup tax is real","url":"https://daily.dev/posts/cloudflare-python-workers-are-ga-but-the-startup-tax-is-real-h5uc0vknh","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/cloudflare-python-workers-are-ga-but-the-startup-tax-is-real-h5uc0vknh"},"datePublished":"2026-09-22T14:09:17.577Z","dateModified":"2026-09-22T14:10:05.044Z","description":"Cloudflare Python Workers reached general availability, giving Python first-class status alongside TypeScript on the platform, with native ASGI/WSGI support...","isAccessibleForFree":true,"articleSection":"Trends","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"Trends","logo":"https://media.daily.dev/image/upload/s--ZfSp3asX--/f_auto,q_auto/v1780996004/logos/trends?_a=BAMAMiWQ0","url":"https://daily.dev/sources/trends"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/cloudflare-python-workers-are-ga-but-the-startup-tax-is-real-h5uc0vknh","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":1},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"python,serverless,webassembly,cloudflare","timeRequired":"PT2M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Trends","item":"https://daily.dev/sources/trends"},{"@type":"ListItem","position":3,"name":"Cloudflare Python Workers are GA, but the startup tax is real"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/cloudflare-python-workers-are-ga-but-the-startup-tax-is-real-h5uc0vknh#faq","mainEntity":[{"@type":"Question","name":"Are Cloudflare Python Workers ready for production use now that they're generally available?","acceptedAnswer":{"@type":"Answer","text":"Yes, Cloudflare Python Workers reached general availability, supporting FastAPI, Django, and Flask natively via ASGI/WSGI connectors, with access to D1, R2, Durable Objects, and Hyperdrive for PostgreSQL/MySQL. 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