Claude Fable 5.1 & GPT-6 Astra packages are live

express

Backend

Express application structure — router organisation, async error handling, security defaults, request context, and testing without a live server.

Choose your model

Available for 11 model families. The engineering substance is the same in each; the structure, checklist phrasing and constraint ordering are tuned per family.

Claude

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Deepseek

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Gemini

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Glm

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Grok

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Kimi

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Minimax

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Mistral

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Open Ai

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Qwen

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Sarvam Ai

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